FERTILITY UPDATE F ERTILITY U PDATE August 2008 Vol 10 No 2 Alterations of the Y-Chromosome and Male Infertility Management of Prostate Pathology Recurrent Implantation Failure: The Therapeuatic Approach Ovarian Hyperstimulation Syndrome (OHSS) Are there predictive factors? Rubella Virus: An Underestimated Pathogen in Nigeria? 1 Vol 10 No 2 FERTILITY UPDATE THE BRIDGE CLINIC PROFILE T he Bridge Clinic is Nigeria’s first focused assisted conception clinic. It was set up in collaboration with consultants from the prestigious King’s College Hospital, London, in 1999 to make assisted conception treatment available in Nigeria. We batched patients for treatment between 1999 and 2000 and during this period, the team from UK would come to Nigeria and treat the batches. At the same time, we sent some staff to The King’s College Hospital to receive requisite training. The team from King’s College was able to hand over to the Nigerian team by April 2001. Since then, the day-to-day operations of the clinic have been run by the Nigerian team. The science of reproduction is a rapidly advancing subject and in addition to the hands-on training received, we register our embryologists in particular for the M.Sc programme at the University of Leeds. We have to date successfully trained 2 embryologists to M.Sc level and have a third in the programme Furthermore, we have maintained our relationship with the King’s College Hospital and they attend regularly to audit the activities of the clinic. The Mission of The Bridge Clinic is to use our knowledge of the science of reproduction to provide hope for couples that desire children. God has supported our mission and to date; 756 babies have been born following treatment at the Lagos clinic. We have also had the birth of 111 babies at our Port Harcourt clinic. The first conception and live birth following Intracytoplasmic Sperm Injection (ICSI); The first conception and live birth following ICSI with surgically collected sperms; The first birth following in vitro Fertilisation (IVF) and gestational surrogacy; The birth of a child of the desired sex for family balancing, following ICSI with ‘sorted’ sperm; and The first clinic in West Africa to recieve a Certificate for implementing the ISO 9001: 2000 Quality Management System. The Bridge Clinic, Lagos Clinical Staff Consultant Gynaecologists Dr R A Ajayi Dr A I Arilesere Dr O Adeyemi-Bero Board of Directors Chief (Dr) O A Finnih - Chairman Dr R A Ajayi - Managing Director Dr F A B Coker Dr (Mrs) P I Ajayi Chief G K Animashawun Mr Biodun Dabiri The Bridge Clinic, Port Harcourt Clinical Staff Consultant Gynaecologists Dr R A Ajayi Dr P Feibai Editorial Committee Embryologists Femi Akinrinola Dayo Yussuf Omonigho Osemeikhian Lauretta Mbaeze Segun Babatunde Olajide Wilson Client Coordinators 2 Simisola Akintujoye Sandra Ahmed Promise Ubali Ebele Onwuagbaizu China Mereghini Patricia Ekechukwu Abidemi Adesanya Anita Uzowuru-Ajayi Mary Olasore Vol 10 No 2 Dayo Yusuf Ebele Onwuagbaizu Dr Femi-Adebayo Embryologist (P.H) Obianuju Ukoha Client Coordinators (P.H) Rachel Oga Queen Ahiwe Fortune Mgbekei FERTILITY UPDATE Editorial T his is the first edition of Fertility Update which is completely electronic. We believe we will have a wider coverage through this media. If you will like to be on our mailing list, kindly send your e-mail address to [email protected]. In this issue we discuss chromosomal abnormalities and male infertility. Another topical issue is the management of prostate pathology and we talk about the latest techniques available for this. The success rates for IVF treatment is 25 – 30% and implantation failure contributes to the high failure rate; the third article discuses this in detail. The fourth article examines Ovarian Hyper-Stimulation Syndrome, acomplication of IVF treatment which can be quite severe. Earlier this year, there was an outbreak of Rubella in Northern Nigeria, the final article discusses preventive measures for this disease. Have an exciting read. The Editor P O R T HARCOURT L AGOS 41A Evo Road, G.R.A. Phase II, Port Harcourt. Plot 1397A Tiamiyu Savage Street, Victoria Island, Lagos. TEL: +234 - 1 - 461 9006 TEL: +234 - 84 - 763 975, 793 531, 764 664, 465 003-5, 0702 814 2295 FAX: +234 - 84 - 231627 FAX: +234 - 1 - 461 2807 E --M M A I L: [email protected] W EBSITE: www.thebridgeclinic.com 3 Vol 10 No 2 FERTILITY UPDATE Alterations of the Y-Chromosome and Male Infertility Omonigho Omolara OSEMEIKHIAN Trainee Embryologist THE BRIDGE CLINIC, LAGOS Introduction The human Y chromosome plays an essential role in human biology. The presence or absence of this chromosome determines gender of an individual. Therefore, mammalian embryos with the Y chromosome develop testis (male) while those without it develop ovaries (females). 1 The Y chromosome is one of the smallest chromosomes in the human genome and is divided into many portions as a result of cytogenetic observations based on chromosome banding studies.2 Structure of the Y Chromosome The Y chromosome (Fig.1) is divided into two arms by a centromere, the short arm (p) and the long arm (q). The terminals of both arms are referred to as pseudoautosomal regions. These regions pair and also exchange genetic materials with the pseudoautosomal regions of the X chromosome during male meiosis. Fig.1. The Human Y chromosome Following the pseudoautosomal region of the long arm is the heterochromatic region. This region is assumed to be genetically inert and polymorphic in length in different male populations. It is also the portion that retains a record of mutational events that have occurred along the male lineage throughout evolution. This is because it is holoandrically transmitted from father to son without recombination during meiosis. All the other portions of the Ychromosome, apart from the pseudoautosomal regions and the heterochromatic region are referred to as the euchromatic region. This region consists of numerous highly repeated gene sequences and also contains genes responsible for male fertility. 2 4 Vol 10 No 2 The Y Chromosome And Male Infertility The occurrence of grossly cytogenetically detectable and unexplained deletions in six azoospermic individuals, describing for the first time the role of the Y chromosome in spermatogenesis, was reported in 1976.2 These observations led to the postulation of the existence of a locus, called Azoospermic factor (AZF), on the long arm of the Y chromosome (Yq), required for complete spermatogenesis since the seminal fluid of these patients did not contain mature spermatozoa. The location of AZF in Yq was further confirmed by numerous studies at cytogenetic and molecular level.3 4 5 The original AZF region was further subdivided into three different non-overlapping sub regions on Yq, all associated with male infertility.6 They were named AZFa, AZFb, and AZFc regions. Each of these regions contains several genes proposed as candidate genes involved in male factor infertility. The AZFa region is located in the proximal Yq. Several genes have been identified in this region and only the Drosophila Fats Facets Related Y (DFFRY) gene or Ubiquitin-specific protease (USP9Y) gene has been proposed to play a role in gametogenesis. It encodes a protein involved in deubiquitination (the process by which proteins are tagged for degradation) and mutations in Drosophila homologue of the gene cause a sterile phenotype. 7 8 FERTILITY UPDATE The AZFb region follows immediately after the AZFa region and has been estimated to be of the same molecular extension as the AZFa region (1-3Mb). Five genes have been described within this region among which only three are related to male infertility. The RNA binding motif gene (RBM gene) encodes germ cell specific nuclear proteins containing RNA-binding motif and it is present in multiple copies along the Y chromosome. However, not all of these copies are functional and most may be pseudo genes. It has been strongly proposed as a candidate infertility gene since its expression is testis-specific, it is recurrently deleted in azoospermic men and it seems to be specifically expressed in spermatogonia and primary spermatocytes. 9 10 The two other genes expressed specifically in adult testis which are also recurrently deleted in infertile males are the Chromodomain Y (CDY) gene and the XK Related Y (XKRY) gene. The AZFc region is located in the proximity of the heterochromatin region and its molecular extension is about 500Kb.11 The Deleted in Azoospermia (DAZ) gene cluster is located in this region and encodes a testis specific RNA binding protein.11 There are at least six to nine copies of the DAZ gene in this region and although it has been proposed as the cause of the AZFc phenotype, other genes must be involved since deletions within AZFc region without including DAZ have been recently reported. 12 13 14 The other genes identified within this region, PTPBL Related Y (PRY) gene, Basic Protein Y2 (BPY2) gene, and Testis Transcript Y2 (TTY2) gene, also present a testis-specific expression and are present in multiple copies on the Y chromosome. Although the exact interrelationship between spermatogenesis and the coding sequence for these Deleted Region (Genotype) AZFa AZFb AZFc 5 3 Vol 10 No 2 particular regions remain ambiguous, research has linked particular AZF deletions with observable changes in the spermatogenetic process (Table 1) Additional genes affecting spermatogenesis both within the Y chromosome and along other chromosomes are possible, further complicating the etiology. Genetic screening of male infertility patients and their offspring demonstrated the heritability of micro-deletions in their Y-chromosomes. Further research has substantiated that all males with micro-deletions will either pass on those same micro-deletions or even larger mutations to their male children.6 This can be as a result of either aberrant crossover events or unbalanced sister chromatid exchange during meiosis. These deletions can in rare cases be passed on through sexual intercourse and can certainly be passed on using assisted reproductive techniques, such as intrauterine insemination (IUI), in vitro fertilization (IVF), and intracytoplasmic sperm injection (ICSI). 15 16 17 Clinical Implications of Y Chromosome Deletions There is currently no treatment to improve fertility in men with Y-chromosome deletions. However, knowledge of a Y-chromosome micro deletion is useful for several reasons. First, detection of a Ychromosome deletion provides a diagnosis for infertility, and patients usually want to know why they are infertile. Second, a diagnosis of a Y-chromosome micro deletion allows the physician to forego empirical treatments and to direct the patient to assisted reproduction or adoption. Perhaps the knowledge of Y-chromosome micro deletions will allow couples that go on to conceive by assisted reproduction techniques inform their male children of their potential fertility challenges. This is because there is a Table 1 high possibility that at a later age, they might experience infertility. With Effect prior knowledge of a Y-chromosome (Phenotype) micro deletion, the child’s male factor Oligozoospermia or spermatogenic infertility need not be a surprise, as it arrest probably was from his father, but Azoospermia, Oligozoospermia or rather an expected problem for which normal sperm counts with appropriate counselling and planning teratozoospermia may be done in advance. Azoospermia or Oligozoospermia FERTILITY UPDATE Conclusion Research into male infertility remains productive and continuous. Investigations to determine the origin and transmission of mutations, as well as the refinement of the epidemiological parameters related to infertility should be encouraged. In the nearest future, researchers should eventually be able to correct congenital birth defects. Although the exact etiology remains highly complex, the replacement of mutated strands of the Y-chromosome through advanced gene therapy may prove to be useful in the restoration of male fertilization potential at the genetic level. References 1. Polani, P.E. (1981) Experiments on chiasmata and nondisjunction in mice. Hum Genet Suppl., 2, 145-146. 2. Tiepolo, L., Zuffardi, O. (1976) Localization of factors controlling spermatogenesis in the nonflourescent portion of the human Y chromosome long arm. Hum Genet. 34, 119-124. 3. Ferguson-Smith, M.A., Affara, N.A., Magenis, R.E. (1987) Ordering of Y-specific sequences by deletion mapping and analysis of X-Y interchange males and females. Development Suppl., 101:41–50. 4. Anderson, M., Page, D.C., Pettay, D. et al. (1988) Y autosome translocations and mosaicism in the etiology of 45, X maleness: assignment of fertility factor to distal Yq11. Hum Genet., 79:2–7. 5. Bardoni, B., Zuffardi, O., Guioli, S. et al. (1991) A deletion map of the human Yq11 region: implications for the evolution of the Y chromosome and tentative mapping of a locus involved in spermatogenesis. Genomics., 11:443–451. 6. Vogt, P.H., Edelmann, A., Kirsh S. et al. (1996) Human Y chromosome azoospermia factors (AZF) mapped to different subregions in Yq11. Hum Mol Genet., 5:933–943. 7. Fischer-Vize, J.A., Rubin, G.M., Lehmann, R. (1992) The fat facets gene is required for Drosophila eye and embryo development. Development. 116:985– 1000. 8. Brown, G.M., Furlong, R.A., Sargent, C.A. et al. (1998) Characterisation of the coding sequence and fine mapping of the human DFFRY gene and comparative expression analysis and mapping to the Sxrb interval of the mouse Y chromosome of the DFFRY gene. Hum Mol Genet. 7:97-107. 46 Vol Vol 10 10 No No 22 9. Ma, K., Inglis, J.D., Sharkey, A. et al. (1993) A Y chromosome gene family with RNA-binding protein homology: candidates for the azoospermia factor AZF controlling spermatogenesis. Cell., 75:1287–1295. 10. Eliott, D.J., Millar, M.R., Oghene, K. et al. (1997) Expression of RBM in the nuclei of human germ cells is dependent on a critical region of the Y chromosome long arm. Proc Natl Acad Sci USA., 94:3848–3853. 11. Reijo, R., Lee, T.Y., Salo, P. et al. (1995) Diverse spermatogenic defects in humans caused by Y chromosome deletions encompassing a novel RNA-binding protein gene. Nat Genet., 10:383–395. 12. Stuppia, L., Mastroprimiano, G., Calabrese, G. et al. (1996) Microdeletions in interval 6 of the Y chromosome detected by STS-PCR in 6 of 33 patients with idiopathic oligoand azoospermia. Cytogenet Cell Genet., 72:155–158. 13. Najmabadi, H., Huang, V., Yen, P. et al. (1996) Substantial prevalence of micro deletions of the Ychromosome in infertile men with idiopathic azoospermia and oligospermia detected using a sequence tagged site based mapping strategy. J Clin Endocrinol Metabol., 81:1347–1352. 14. Foresta, C., Ferlin, A., Garolla, A. et al. (1997) Ychromosome deletions in idiopathic severe testiculopathies. J Clin Endocrinol Metabol., 82:1075– 1080. 15. Kent-First, M.G., Kol, S., Muallem, A., Ofir, R., Manor, D., Blazer, S., First N. and Itskovitz-Eldor, J. (1996b) The incidence and possible relevance of Ylinked microdeletions in babies born after intracytoplasmic-sperm injection and their infertile fathers. Mol Hum Reprod., 2:943-950. 16. Mulhall, J.R., Reijo, R., Alagappan, R., Brown, L., Page, D., Carson, R. and Oates, R.D. (1997) Azoospermic men with deletion of the DAZ gene cluster are capable of completing spermatogenesis-fertilization. normal embryonic development and pregnancy occur when retrieved testicular spermatozoa are used for intracytoplasmic sperm injection. Hum Reprod., 12:503-508. 17. Pryor, J.L., Kent-First, M., Muallem, A., Van Bergen, A., Nolten, W.E., Meisner, L. and Roberts, K.P. (1997) Microdeletions in the Y chromosome of infertile men. N Eng J Med., 336:534-539. FERTILITY UPDATE Management of Prostate Pathology Mr. Adeleye AJAYI MBBS (Lond) MD (Eng) FRCS (Eng) FRCS (Urol) CONSULTANT UROLOGICAL SURGEON ROYAL FREE HOSPITAL, LONDON Epidemology of Prostate Cancer Prostate cancer is the second commonest cause of death from cancer in the western world with 198,000 new cases and 31,500 deaths in the USA in 2001 with a 16.6% lifetime risk of the disease and a 3.4% lifetime risk of death. The exact incidence of prostate cancer in Nigeria is unknown as no epidemiological data is available. However, anecdotal evidence suggests that prostate cancer is common in Nigeria with a high mortality rate. Patients often present with incurable metastatic disease as there is no national screening program and public awareness is limited. Diagnosis and Staging of Prostate cancer Patients may present with obstructive lower urinary tract symptoms in the form of hesitancy, poor urinary stream, frequency of urine or heamaturia. A large percentage of patients present with features suggestive of metastatic disease with lower lumbar back pain or caudia equina nerve route compression causing lower limb paralysis, urinary retention, priapism or constipation. A patient undergoing investigation for suspected prostate cancer requires a Digital Rectal Examination (DRE) to assess the size and consistency of the prostate gland and a Prostate Specific Antigen (PSA) blood test. PSA is useful in the detection, staging and monitoring of prostate cancer. A normal serum PSA level is <4mg/l. Although PSA is prostate specific, it is not cancer specific and its value can be elevated in patients with Benign Prostatic Hyperplasia (BPH), Prostatitis, and Urinary retention. There is an ongoing quest to find a tumour marker which has a high sensitivity and specificity. A promising marker is urinary PCA3 gene test. A new test in which the higher the urinary PCA3 Score, the greater the likelihood of prostate cancer. Although this test is available in clinical practice, its exact role is yet to be defined. A transrectal ultrasound guided prostate biopsy under local anaesthetic is required in order to obtain histological diagnosis of prostate cancer. A metastatic search is performed using Bone scan. This is indicated if the PSA >20mg/l. A CT Scan & MRI Scan is useful to exclude extraprostatic capsular disease. 75 Vol Vol 10 10 No No 22 Treatment options for localized prostate cancer There are a number of treatment options available to a patient with prostate cancer and appropriate informed discussion is required in order to tailor the treatment to the patient. These range from observation or active monitoring of the patient to more aggressive treatment options such as external beam radiotherapy and radical prostatectomy (retropubic or perineal). These treatment options produce satisfactory outcomes with high cancer specific survival rates. However, the potential complications (blood transfusion, rectal injury) and long term side effects such as impotence and incontinence makes these treatments difficult for the patients to accept. There are now minimally invasive treatment options such as Brachytherapy, High Intensity Focused Ultrasound, Laparoscopic or Robotic Prostatectomy which have encouraging results with lower long term complications. Dietary Prevention of prostate cancer Patients often enquire about dietary measures to reduce their risk of developing prostate cancer. Dietary suggestions include Soya beans (phytoestrogens), Green Tea, Selenium-protects cell from oxidative damage, Vitamin E an intracellular antioxidant and agents high in Lycopenes (Tomato & watermelon). FERTILITY UPDATE X-ray of radioactive Brachytherapy seeds in the prostate Benign Prostatic Hyperplasia (BPH) The prostate is one of four accessory sex glands in a male weighing an average of 18grams. BPH is a histological diagnosis with increased prostatic epithelial and stromal cells in the periurethral area. Patients present with storage (frequency, urgency, nocturia, incontinence) or voiding (hesitancy, poor stream and post micturition dribbling) lower urinary tract symptoms. Occasionally they present with heamaturia and acute retention of urine The evaluation of a patient includes a focused history and a targeted examination including a Digital Rectal Examination to assess the size of the prostate and identify any suspicious prostatic mass. Serum PSA to assess for prostate cancer and creatinine blood test to ensure the patient has not developed obstructive uropathy. An International Prostatic Symptom Score (IPSS) is completed by the patient to assess the severity of their symptoms. A urine dipstix is done to exclude a urinary tract infection. The patient is then invited to perform a Uroflowmetry to obtain objective evidence of the patients urinary flow rate together with a post void bladder scan to assess the post void residual volume. Medical Treatment Medical treatment involves the use of a1 Alpha blockers (Alfuzosin, Tamsulosin or Doxazosin)- This 68 Vol 10 No 2 Schematic diagram illustrating HIFU treatment for Prostate cancer group of medications improve symptoms and increase urinary flow rate by relaxing prostatic and bladderneck smooth muscle through sympathetic activity blockade. Potential side effects include postural hypotension, dizziness, blurred vision and retrograde ejaculation. Another class of medication are 5-a reductase inhibitors (Dutesteride and Finasteride) which increase urinary flow rate and prevent BPH progression by reducing prostate growth through The da Vinci Robot used to perform radical prostatectomy for cancer FERTILITY UPDATE Green light laser used to treat patients with BPH hormonal mechanisms. Erectile dysfunction is reported in -5% of patients, therefore it is important the patient is aware of this potential side effect, which is reversible by stopping the drug. These two classes of drugs can be used in isolation or in combination. The current trend is to use them in combination. the role of Phytotherapy is yet to be determined. Surgical Treatment Transurethral Resection of the Prostate (TURP) has been the Gold standard for over 25 years. This procedure is often performed under spinal anaesthetic with the patient fully awake. A retrospective study of 5,000 cases published as the British National Prostatectomy Audit revealed satisfactory results with 65% patients reporting a 13 point drop in their IPSS score, all patients reported an improvement in flow rate with 90% of patients reporting that they are satisfied with the outcome. However, 70% of patients reported retrograde ejaculation, 10% impotence and a blood transfusion rate of 5%. These side effects are not acceptable to the patient: therefore, there are continued efforts to develop equipment which can reduce these side effects. One such mechanism is the use of the Green light laser photoselective vaporisation of prostate (PVP). The Laser light is produced by Nd YAG laser and fired through KTP crystal which doubles the frequency of the light. The green colour of the laser is rapidly absorbed by Heamoglobin which is extremely 9 7 Vol 10 No 2 Animated picture showing the residual cavity of the prostate following Green light laser prostatectomy. valuable as the Prostate has an excellent blood supply and allows for prostatic tissue to vaporise with little bleeding as vessels are sealed at the time of vaporisation. This technique allows patients to be treated and discharged on the same day. A significant percentage of patients are catheter free within 24hrs. Very large prostates can be vapourised preventing the need for the old fashion open Millin’s retropubic prostatectomy. The side effects are much less than TURP with 1% impotence, 36% retrograde ejaculation and no blood transfusion. With increasing use of this technique, one can predict the Green light laser will be the Platinum standard for treating patients with BPH. FERTILITY UPDATE Recurrent Implantation Failure: The Therapeuatic Approach Rachel Oga Senior Fertility Nurse The Bridge Clinic, PORT HARCOURT INTRODUCTION: Recurrent Implantation Failure is an issue of concern to In-vitro fertilisation (IVF) practice and also to the patient concerned. For many couples with infertility issues, IVF constitutes the last resort in the line of infertility management. Over 70% of the treated cases will not be successful, with implantation failure being touted as a major contributory factor. The reasons for IVF cycle failure could be very complex, and it has been difficult to find a lasting solution despite extensive ongoing research. The underlying cause for IVF failure has been attributed to problems with the embryos, the uterine environment, or the patient’s immune system˙. The Embryos and Age As women advance with age, the quality of their eggs begins to decline. The overall effect is on the resulting embryo, which at that stage is associated with high incidence of chromosomal abnormalities. Embryos with such abnormal chromosomal components are thus likely to be lost soon after transfer or do not implant at all. In addition, women with diminished ovarian reserve (high FSH level on cycle day 3 etc.) are more likely to produce fewer eggs of poor quality, which is eventually transferred to the developing embryos. One of the associated characteristics of clients with recurrent IVF failure is a thick zona pellucida, which is a common feature in women with advanced age, high FSH level, and recurrent implantation failure history. To overcome this potential problem, a technique known as assisted hatching has been developed and applied in-vitro, prior to embryo transfer procedure to trim or reduce the zona thickness with a view to aiding implantation. With this same technique, skilled embryologists can also remove fragments (cellular debris between the cells) from “poor quality” embryos, thus improving their potential for implantation.1 10 8 Vol 10 No 2 Problems within the Uterus Problems within the uterine environment that inhibits the embryo from implanting have been classified as anatomic, hormonal and immunologic. A. Anatomic abnormalities are lesions inside the uterus that mechanically inhibit implantation. These anatomic abnormalities act like an intrauterine device to prevent implantation of the embryo. These include: Endometrial polyps— benign outgrowths of the uterine lining that protrude into the uterine cavity) Submucous fibroids – benign tumors of the uterine wall that protrude into the uterine cavity Uterine synechia - scarring or adhesions inside the uterine cavity Evaluation of the uterine cavity to rule out fibroids, polyps or scar tissue is a routine practice by most assisted conception units. Uterine evaluation is usually accomplished with a hysterosalpingogram (HSG) or a saline infusion ultrasound (sonohysterography). Patients with good quality embryos that fail to conceive would require a more thorough evaluation of the uterine cavity to rule out any uterine factors FERTILITY UPDATE that might be responsible. Recent studies have shown that hysteroscopy often provides significant findings in this group of patients.˙ B. Hormonal responses of the lining of the uterus to both estrogen and progesterone are necessary for the uterus to be receptive to the embryo. Mutations in some of the genes encoding for the progesterone receptor have been associated with recurrent implantation failure. C. Immunologic mechanisms involved in implantation are being identified. The uterus as well as the embryo has to be made amenable to implantation. Uterine receptivity requires continuous interactions between the embryo and the mother. These interactions are communicated through proteins known as cytokines. The cells within the uterine lining including the immune cell secrete cytokines. During the preimplantation period preparation of the uterine lining for implantation involves stimulation expression of adhesion systems that hold the embryo to the uterus. If the immune cells do not send proper signals through secretion of appropriate cytokines to the embryo or if these cells do not respond to signals from the embryo, then adhesion and thus subsequent implantation will not occur. This immunological interaction during implantation has been implicated as a cause of recurrent implantation failure˝. Preferred Therapeutic Approach PGD (Pre Implantation Genetic Diagnosis) and PGAS (Pre implantation Genetic Aneuploidy Screening) N PGAS enables the assessment of the numerical chromosomal constitution of cleavage stage embryos through the of fluorescence in-situ hybridization (FISH). Theoretically, the selection of euploid embryos for transfer would result in a higher implantation and pregnancy rate and a reduced miscarriage rate . Recent advances in reproductive medicine and molecular cytogenetics have changed the approach to the management of infertile couples. The introduction of FISH has enabled the chromosomal assessment of embryos. The initial application of pre 11 9 Vol 10 No 2 implantation genetic diagnosis (PGD) to prevent xlinked recessive diseases and the unbalanced transmission of parental balanced translocations has widened to improve IVF results in repetitive implantation failure. PGD for aneuploidy screening has also been investigated in patients with unexplained recurrent spontaneous pregnancy loss. It is theorized that PGD could improve the possibility of successful pregnancy in this population, as a large proportion of embryos about 50%-70% are chromosomally abnormal. In a pilot study, Wilding and colleagues reported that in patients with a history of recurrent abortion, IVF outcomes were better with the analysis of 5 chromosomes as opposed to 3 chromosomes, although no control group was available for comparison. The authors state in their analysis that it is not clear from the limited sample of patients whether the protocol described can be applied to all patient groups. They call for a larger, prospective, randomized, controlled, multicenter trial comparing PGD with other IVF protocols to determine the accuracy of their data. Platteau and colleagues reported on a group of 49 patients, divided by age into two groups, those <37 years and those 37 or older. They reported that although the aneuploidy rate was relatively high in the younger population, PGD did not improve the selection of transferred embryos and did not seem to improve the pregnancy rate compared to their general IVF population. Live births were not reported, but the authors suggested that the expected live birth rate in this population would have been the same without any treatment. Results in the older patient cohort were disappointing, and the authors stated that PGD brought no benefit, apart from being diagnostic and redirecting treatment to other options. In general, they concluded there was no therapeutic evidence to prescribe IVF, with or without PGD, for patients with recurrent miscarriages. In a study published in the May 2007 issue of the medical journal Fertility and Sterility, researchers set out to determine if couples that failed to achieve pregnancy with IVF after multiple transfers had a higher incidence of chromosome abnormalities than other patients. FERTILITY UPDATE They looked at data from PGD screening using CGH (comparative genomic hybridization) a second type of PGD. (During CGH, a labeled identical copy of each chromosome in a cell is created. This DNA copy is then hybridized with a labeled copy of DNA from a cell that is known to be normal). This was done on analysis on 176 embryos from 28 women. Twenty-two women had a history of recurrent implantation failure (RIF), and six did not. Women were classified as having RIF when 10 or more embryos had been transferred previously without achieving a pregnancy. The average number of previously transferred embryos in this group was 16.5. The authors created a category of abnormalities that they referred to as “complex”. An embryo was considered to have a complex abnormality if there were 3 or more chromosomes that were not present in correct numbers. Seventy-six (45%) embryos tested normally and were suitable for transfer, 46 (27%) showed aneuploidy for one or two chromosomes, 4% showed partial aneuploidy, and 49 (29%) had complex abnormalities involving three or more chromosome. its constituent glycoproteins has been implicated in reduced hatching rates. AH probably enhances clinical pregnancy, especially in women with previous failure of assisted conception treatment. Assisted hatching is achieved by zona dissection, drilling or thinning, making use of acid solutions, proteinases, piezon vibrators and laser. It is said that hatched embryos implant one day earlier than unhatched embryos. The procedure is increasingly offered to older women, those with high FSH levels, higher risk of zona hardening and following repeated implantation failure. In a 2005 study in Reproductive Biomedicine, a sample of 150 people with previous implantation failure were treated with intracytoplasmic sperm injection and divided into two groups, one with only one previous implantation failure, and the second, with several implantation failures. For group two, those patients who had had laser assisted hatching had a significantly higher rate of pregnancy than those who didn’t (10.9% for those who had laser treatment as opposed to 2.6% for those who didn’t). Blastocyst Transfer Another strategy involves culture to blastocyst stage, thereby allowing self-selection of those embryos capable of proceeding to blastulation and exclusion of less viable embryos showing developmental arrest. The transfer of as many as two blastocysts has been shown on the average to be effective in reducing the number of multiple gestations in patients with good ovarian response and capable of establishing pregnancies in women with previous IVF failures. Generally, a good quality blastocyst contains a well –expanded blastocoelic cavity, homogenous trophoblast with multiple cell-cell contacts and distinct nuclei, and an inner cell mass that is clearly visible and intact. A large number of studies attest to excellent success rates following blastocyst transfer with implantation rates of 67% The Role Of Human Leukocyte Antigens (HLA) Studies have shown that parental Human Leukocyte Antigens lead to implantation failure. Maternal recognition of paternally derived fetal antigens occurs during normal pregnancy and may be beneficial for implantation and maintenance of gestation. Studies have shown that couples with more than 3 implantation failures after IVF have more than 2 shared HLAS. If so, it would be worthwhile to screen couples for HLA compatibility who fail to concieve after multiple IVF attempts. Gamete or embryo donation would be a therapeutic alternative in this case in order to provide the wide Antigen difference between the mother and foetus necessary for successful implantation. Monserrat et al, 1998. Noteworthy though is the fact that these researchers could not identify any specific HLA associated with failure of implantation after ET, but it is still advisable to screen the couple. Assisted Hatching (AH) Cultured embryos develop slowly and poorly in vitro. Many fail to achieve blastocyst stage or hatch, and implant at lower rates than occur naturally. Hardening of the zona pellucida resulting from cross-linking of 10 12 Vol 10 No 2 FERTILITY UPDATE Conclusion The management of recurrent implantation is still evolving, but it would seem like an act of God for pregnancy to occur in the end having exhausted all options available. The issues to critically examine are: how involving are infections of the vagina, cervix and endometrium, and should they not be treated before commencement of treatment? What about the role of mucus aspiration and washing of the cervix on transfer, the role of catheter guidance for a correct transfer and portion of embryos, the effect of mock transfer and the role of hysteroscopy and its timing before embryo transfer procedures. All these put together form the basis for the skilled to be better equipped to improve implantation success. References 1. Claudio Benadiva, MD. Center for Advanced Reproductive Services, Department of Ob/Gyn, University of Connecticut Health Center 2. SHER Institute For Reproductive Medicine 3. P.Donoso et al. Current value of pre implantation genetic aneuploidy screening in IVF, Hum. Rep update (electronic version). 4. Platteau P, Staessen C, Michiels A et al. Preimplantation genetic diagnosis for aneuploidy screening in patients with unexplained recurrent miscarriages. Fertil Steril 2005;83(2):393-7 5. Wilding M, Forman R, Hogewind G. Preimplantation genetic diagnosis for the treatment 13 11 Vol 10 No 2 of failed in vitro fertilization-embryo transfer and habitual abortion. Fertil Steril 2004;81(5):1302-7 6-7. Platteau P, Staessen C, Michiels A et al. Preimplantation genetic diagnosis foraneuploidy screening in patients with unexplained recurrent miscarriages. Fertil Steril 2005;83(2):393-7 8. Gardener DK,Lane,Stevens J et al. Blastocyst score affects implantation and pregnancy outcome: Towards a single blastocyst transfer. Fertil Steril 2000;73:115558 9. Toledo AA.Wright G.Jones et al. Blastocyst transfer: a useful tool for reduction of high-order multiple gestations in assisted reproduction programme. Am J obstet Gynecol 2000;183:377-79 10. Langley DT,Marek DM et al. Extended embryo culture in human assisted reproduction treatment, Hum Reprod 2001:16-902-8. 11. Rijnders PM,Jansen CAM The predictive value of day 3 embryo morphology regarding blastocyst formation,pregnancy and implantation rate after day 5 transfer following in-vitro fert or ICSI. Hum Reprod 1998;13:2869-73 12. Edmond Edi-Osagie et al. The impact of assisted hatching on live birth rates and outcomes of assited conception:a systematic review, Hum.Rep.2003 13. Reproductive BioMedicine Online, Volume 10, Number 2, February 2005 , pp. 224-22 14. Montserrat et al. Dept of Obs & Gyn, Immunology Center, University of Barcelona. Hum. Rep, publication,vol 13,no.1,pp39-43,1998. FERTILITY UPDATE Ovarian Hyperstimulation Syndrome (OHSS) Are there predictive factors? Queen AHIWE Fertility Nurse THE BRIDGE CLINIC PORT HARCOURT Introduction Ovarian Hyper stimulation Syndrome (OHSS) is a systemic disease resulting from vasoactive products released by hyper stimulated ovaries; often triggered by the administration of hCG. The syndrome is characterised by increased capillary permeability, leading to leakage of fluid from the vascular compartment, with third space fluid accumulation and intravascular dehydration. The symptoms usually begin 4-5 days after egg collection. The majority of women have a mild or moderate form of the syndrome and invariably resolve within a few days unless pregnancy occurs, which may delay recovery. OHSS is rarely severe, and as the ovaries are swollen, the woman can experience a pronounced degree of discomfort. Severe OHSS is, perhaps, the most serious complication of IVF. Incidence The incidence of OHSS varies between treatments and patient groups, and accurate estimates from the literature are difficult owing to different definitions of the grades of severity, different criteria for prevention, and the variety of classification schemes used. The incidence at The Bridge Clinic (2003 -2007) averaged 7%. The majority of cases of severe OHSS are seen following IVF treatment. Mild OHSS occurs after any form of supraphysiological ovarian stimulation, including clomiphene and gonadotrophin ovulation induction in a small proportion of women. Further Classification A division of OHSS into ‘early’ and ‘late’, depending on the time of onset, may be useful in determining the prognosis. OHSS presenting within 9 days after the ovulatory dose of hCG is likely to reflect excessive ovarian response and the precipitating effect of exogenous hCG administered for follicular maturation. OHSS presenting after this period reflects endogenous hCG stimulation from an early pregnancy. Late OHSS is more likely to be severe and to last longer than early OHSS. Classification GRADE Mild OHSS Moderate OHSS Severe OHSS Critical OHSS 14 12 Vol 10 No 2 SYMPTOMS Abdominal bloating, mild abdominal pain, slight discomfort, ovaries usually <8cm Moderate abdominal pain, nausea, vomiting, ascites, ovaries 8-12cm. Clinical ascites (occasionally hydrothorax), oliguria, haemoconcentration (haematocrit>45%), hypoproteinaemia, Ovaries >12cm Tense ascites or large hydrothorax, oligo/anuria, thromboembolism, acute respiratory distress, haematocrit >55%. FERTILITY UPDATE Pathophysiology The initial pathophysiological event in severe OHSS is an increased permeability, especially in the enlarged ovaries, due to the local production of prostaglandin, histamine, and the activation of the follicular renin-angiotensin system, leading to the extravasation of fluid into the abdominal cavity. The extravasation of fluid into the abdominal cavity can cause ascites, a contraction of circulatory blood volume, arterial hypotension and a compensatory increase in heart rate and cardiac output, haemoconcentration, and renal sodium and water retention. Renal failure is an expression of an extreme diminution of intravascular volume. Are There Predictive Factors For OHSS? Prediction of OHSS is difficult as the predictive value of most tests is low, although some risk factors may point to the possibility of its occurrence. As such, preventive measures should be considered when treatment is started in high-risk individuals. However, the risk factors include Young Age Occurrence is higher in women <34 years of age Polycystic Ovarian Syndrome (PCOS) Increases risk of occurrence of OHSS because of the increased number of primordial follicles on the ovaries at the resting phase. Polycystic ovaries tend to over respond when they are being stimulated. Low Body Mass Index Women with body mass index of <25kg/m2 are more predisposed to OHSS. Hypogonadotropic Hypogonadism Some women, on investigation, have their basal LH higher than the FSH. This is a reflection of hypogonadotropic hypogonadism, and most at times, a resultant PCOS. These patients have been found to over respond to ovarian stimulation. Previous History Of OHSS OHSS tends to re-occur in subsequent cycles of ovarian stimulation. Response During Stimulation Monitoring of response in high-risk individuals may indicate possibility of OHSS occurring. 15 13 Vol 10 No 2 High Oestradiol level (>3000 pg/ml) pre hCG and during treatment. Oestradiol levels of 3000pg/ml and above, before the administration of hCG and during treatment, should warn the clinician that the client is at a higher risk of OHSS. Use of GnRH agonists and hMG vs FSH Rizk and Smitz reviewed the world literature concerning OHSS after the use of different GnRHa for superovulation in IVF and other related ARTs showed that the use of GnRHa leads to significantly higher preovulatory Oestradiol concentrations, and more frequently to severe OHSS. This may be related to the action of the agonist on the ovary, or to the increased FSH and LH levels as a result of increased exogenous gonadotropin. They reported high affinity GnRH receptors in human granulosa cells at a late stage of follicular maturation. Therefore, it is suggested that the use of FSH offers a safe treatment compared with GnRHa and hMG, resulting in higher pregnancy rates and lower OHSS rates. Excessive follicular development on egg scan Women who develop more than 20 follicles at egg scan stand a higher risk of developing OHSS. Exposure to hCG The preovulatory hCG dose plays an important role in the initiation of OHSS. The role of hCG generated by the presence of a pregnancy may therefore, essentially augment the prevailing condition, initiated by the preovulatory hCG administration. Prevention Of OHSS Prevention of OHSS is always the best strategy. This syndrome can best be avoided by individualized judicious use of fertility medications. Endocrine and ultrasound follicular monitoring to determine patients at risk pre hCG. Reducing or withholding the preovulatory hCG administration, although this could be at the expense of losing the cycle. Luteal phase support with progesterone Cryopreservation of embryos and subsequent replacement Intravenous albumin administration during oocyte FERTILITY UPDATE retrieval may increase oncotic pressure and subsequently reverse the leakage of fluids from the intravascular space. Management Mild OHSS usually resolves within 1-3 weeks. The treatment is conservative, with observation and follow up. On the other hand, severe OHSS requires hospital admission and active monitoring. Strict monitoring of fluid and electrolyte balance is necessary. Fluid replacement therapy and intake and output recording is also needed. Relief of pain and discomfort with analgesics and antacids. NSAIDS should not be used. Ultrasonographic examination provides accurate assessment of ovarian size and the presence of ascites, as well as pleural or pericardial effusions. Chest Xray will provide information on the latter. Paracenthesis is appropriate in women who are distressed due to ascites, and women who are oliguric despite adequate fluid replacement. Transabdominal aspiration is likely to be better tolerated than a vaginal approach. Biochemical monitoring include serum proteins and electrolyte, renal and liver function tests, a cagulation profile, and a blood count. In cases of hypovolaemia, efforts are directed towards a normal intravascular volume and preserving adequate renal function, using colloid plasma expanders or human albumin. Anticoagulant therapy is indicated if there is clinical evidence of thromboembolic complications or laboratory evidence of hypercoagulability. Diuretics should be avoided as they deplete intra- vascular volume. Complications Thromboembolism Miscarriage Pleural Effusion Renal Failure Adnexal torsion Congenital malformations (as a result of drug administration) Summary Ovarian Hyperstimulation is the most serious complication of ovulation induction. PCOS appears to be the major predisposing factor: it is documented in at 16 14 Vol 10 No 2 least 50% of the major series of OHSS. The combination of GnRHa and hMG is associated with a higher incidence of OHSS. OHSS is more frequent in pregnancy than in non-pregnancy cycles. The most effective management of OHSS is its accurate prediction and active prevention. Combined sonography and endocrine monitoring should improve the prediction compared to either method used alone. The presence of 20 or more follicles and a high serum oestradiol >3000 pg/ml should alert the clinician. Delaying hCG will decrease the risk of OHSS, withholding hCG will also reduce OHSS, but at the expense of getting immature eggs. Cryopreservation of embryos and replacement in subsequent cycles is a useful option in IVF programme but does not prevent OHSS completely. In PCOS patients, titration of hMG, or FSH dosage administered gradually and slowly should be used to prevent OHSS. Luteal-phase support using progesterone intravaginally or intramuscularly should be used in cycles at risk of OHSS. References 1. Aboulghar M A, Mansour R T. Ovarian hyperstimulation in the treatment of infertility. Fertil Steril 1989;51: 834-836. 2. Schenker J G, Ezra y. Complications of assisted reproduction techniques. Fertil Steril 1999; 61:411422. 3. Schenker J G, Weinsten D. Ovarian hyperstimulation syndrome: a current survey. Fertil Steril 1987; 30:255-268. 4. Phillips L L, Glanstone W, Van de Wiele R. Studies of hyperstimulation syndrome after administration of human gonadotropins. J Reprod Med 1995; 14:138 5. Kaaja R, Sieberg R, Titinen A,. Severe ovarian hyperstimulation syndrome. Lancet 1998; ii:1043. 6. Smith B H, Cooke I D. Ovarian hyperstimulation: actual and theoritical risks. Br Med J 1991; 298:127-128 7. Ong A C M, Eisen V, Rennie D P et al. The pathogenesis of the ovarian hyperstimulation syndrome. Clin Endocrinol (Oxf) 1991; 34:43-49. 8. Forman R G, Frydman R, Barlow D. Severe OHSS using GnRHa in IVF: a proposal for prevention. Fertil Steril 1990; 53:938-943. 9. Rizk B, Aboulghar M. Complications of ART. 1994 (in press). 10. Rizk B, Smitz J. Ovarian hyperstimulation syndrome after superovulation for IVF and related procedures. Hum Reprod 1992; 7:320-327. FERTILITY UPDATE Rubella Virus: An Underestimated Pathogen in Nigeria? Dr Folasade T. Ogunsola (MBCHB, FMC Path, FWACP, Ph.D) Department of Medical Microbiology and Parasitology COLLEGE OF MEDICINE, UNIVERSITY OF LAGOS Introducton The Rubella virus is the aetiological agent of Rubella (“German measles”, “3-Day measles”) and Congenital Rubella Syndrome. It is an enveloped RNA virus that belongs to the family Togaviridae. There is only one serotype and humans are the only known host. It does not cross react with any other virus. It is transmitted by the respiratory route and replicates in the nasopharyngeal mucosa and local lymph nodes prior to a generalised viraemia. In pregnant women the virus directly infects the placenta and the developing fetus. Epidemiology Rubella is a contagious viral infection characterized by a distinctive red rash. It has an Incubation period of 12 to 23 days, and it is infectious from one week before the onset of the rash until about two weeks after the rash disappears. It has a worldwide distribution and in endemic areas, epidemics occur every 59 years. In endemic areas children are infected between the ages of 6-12 years in industrialized areas and 2-8 years in urban areas of developing countries. World wide, the extent of susceptibility in women of childbearing age varies considerably from <5% in Kuwait to 30% in Nigeria and 60% in rural Panama. Immune Response Infection usually confers permanent immunity. Antibodies are first detectable about 14-18 days after onset of infection which tends to coincide with the appearance of the rash. There is an initial IgM response that wanes rapidly and may be undetectable by 4-8 weeks. This is followed by an IgG response which may be persistent. Rubella-specific cell-mediated lymphocyte response begins a week after the humoral response and appears to persist for a lifetime. Babies born to immune mothers are protected by maternal antibodies for the first 6-9 months of life 17 15 Vol Vol 10 10 No No 22 Clinical Features Most infections are subclinical and the signs and symptoms are often very mild and difficult to notice and last about 2-3 days. They may include mild fever ≤ 38.9oC (102oF), headache, Stuffy or runny nose, inflamed, red eyes, enlarged, tender lymph nodes characteristically at the base of the skull, back of the neck and behind the ears. A fine, pink rash that begins on the face and quickly spreads to the trunk and then the arms and legs, before disappearing in the same sequence is sometimes reported. Complications are usually few and include arthritis in the fingers, wrists and knees, otitis media or encephalitis. However, infection in early pregnancy (from just before conception and first 8-10 weeks of gestation) are associated with multiple fetal defects in up to 90% of cases and many of these pregnancies will result in miscarriage or stillbirth. Fetal defects are rare with maternal rubella after the 16th week of pregnancy. Clinical features of Congenital Rubella Syndrome The major signs are congenital heart disease , ocular defects and sensorineural hearing loss. Other important signs and symptoms considered minor include failure to thrive, developmental delays, microcephaly, mental retardation, thrombocytopaenia, purpuric FERTILITY UPDATE rash, radiolucent bones on x-ray, hepatosplenomegaly, meningoencephalitis, hepatitis and jaundice that begins within 24 hours after birth. Diagnosis Rubella infection requires laboratory confirmation, particularly under non-epidemic conditions but there are criteria for clinical confirmation of CRS:, an infant with either 2 major signs or 1 major and 1 minor sign. A probable CRS is an infant with heart disease, suspected hearing impairment, or at least 1 eye sign consistent with a diagnosis of Congenital Rubella Syndrome. Serology is the preferred method for routine laboratory diagnosis and is usually by ELISA. A laboratory-confirmed CRS is an infant with positive serology for rubella IgM and clinical signs consistent with a diagnosis of CRS. Samples should be taken within 28days of onset of rash for the demonstration of IgM. If this is not possible, a significant rise in rubella IgG from paired acute and convalescent sera also provides evidence of ongoing or recent rubella infection. Viral isolation is labour-intensive and costly and is not routinely used for diagnosis though the virus can be isolated from the pharynx or urine of an infant with CRS for one year or more. Antenatal screening for Rubella: Pregnant women should be screened within 4-6 weeks of a rash especially in the first trimester to detect IgM antibodies. Routine screening is usually done at about 12-20 wks of gestation for IgG. The laboratory reports are usually qualitative for IgG titre and are reported as “immune” (> 15 IU/mL) or “nonimmune”. A limitation is that routine tests cannot detect substantial rises in IgG levels (indicating possible infection) nor can they differentiate between vaccineinduced immunity and infection acquired in early pregnancy. They also cannot detect low or borderline IgG levels (re-infection resulting in Congenital Rubella Syndrome has occurred at low levels of immunity). Treatment Infected persons should be isolated from others, especially pregnant women. Pregnant women who contract rubella may have to terminate the pregnancy or use hyperimmune globulin, which can reduce 18 16 Vol 10 No 2 symptoms but does not eliminate the possibility of the baby developing CRS. Prevention Most common is the trivalent MMR (Mumps-MeaslesRubella) based on the live attenuated RA 27/3 strain of the virus grown in Human diploid cells. The first dose is given at 12 - 15 months of age and the 2nd dose is given at 4 - 6 years (before entering school). It is safe and efficacious. It is important that girls receive the vaccine to prevent rubella during future pregnancies. Vaccine should not be given to pregnant women or to a woman who may become pregnant within one month of receiving the vaccine. Women thinking about becoming pregnant, should receive the vaccine at least one month before becoming pregnant. Usually babies are passively protected from rubella for 6-8 months after birth Most people experience no side effects from the vaccine and there is no scientific evidence to link the MMR vaccine and autism. Key points Rubella is endemic in Nigeria as about 30% of women of child bearing age are susceptible. Therefore all young women should be vaccinated against Rubella. Children with any of the major and minor signs should be investigated for presence of Rubella IgM. Women should be screened for rubella susceptibility at each pregnancy. Women with a low positive IgG titre (e.g., 10– 15 IU/mL) before pregnancy may benefit from (repeat) rubella vaccination. Pregnant women with a low positive IgG titre, who have recently been exposed to rubella, should be screened for Rubella IgM to help distinguish between new infection and immunity. All pregnant women found to be negative for Rubella should be Vaccinated in the immediate Postpartum period. There is a need for Nigeria to join other Nations in introducing the MMR into the National Programme on Immunisation.
© Copyright 2024