Outcomes of controllled ovarian hyperstimulation for assisted reproduction
Background Infertility affects more than 80 million people worldwide with rates varying from less than 5% to more than 30% (1). The success ofIVF treatment depends on adequate follicle recruitment which is achieved through controlled ovarian hyper stimulation. Overall, the incidence of poor response to assisted reproductive treatment is estimated to be 9 - 24 % (2). However the definition of poor response has been inconsistent using total number of oocytes retrieved, different numbers ofM 2 oocytes ranging from <3 to 6 or minimal cumulative dose of gonadotrophins to define ovarian response (3,4). Objective To describe the outcomes of controlled ovarian hyperstimulation and factors associated with ovarian response. Study design A descriptive observational study. Method This was a descriptive observational study carried out at the IVF unit of The Aga khan university hospital from April 2008 to July 2009. Patients underwent controlled ovarian hyperstimulation using the GnRH agonist or GnRH antagonist protocol followed by transvaginal ultrasound guided aspiration of oocytes under sedation and oocyte quality was then determined by an embryologist. After obtaining ethical approval, recruitment of study participants who met the inclusion criteria was done. Data was obtained from patient records using a data collection form. Data analysis Data was analysed using SPSS version 15.0 and stata version 10 (stataCorp, texas) Results A total of 62 participants were studied, the mean age was 33.5 with a median of 34 years. Fifty one (79.7%) patients underwent GnRH agonist stimulation, the rest GnRH antagonist stimulation, whereby the mean dosage of exogenous gonadotrophins was 3012.8 i.u. The mean number of oocytes retrieved was 10.4 with a median of9, and good quality (M 2 quality) oocyte recovery rate was 59.6%. The mean oocyte count in women < 30 years was 15.3 as compared to 9.4 in women> 30 years which was significant with a p- value = 0.007. The mean dosage requirement in women < 30 years was 2337.5 i.u and in those> 30 years, it was 3187.20 i.u. Poor responders ﾫ 6 oocytes) were older (mean age 35.21 vs. 31.19 years P=O.OOl) and received higher doses of exogenous gonadotrophins (mean dose 3559.84 i.u vs. 2391.35 i.u P<O.OOI) as compared to the normoresponders. Conclusion In this study we found that, outcomes of assisted reproduction in terms of quantity and quality of oocytes, as well as total exogenous gonadotrophins requirement varied with age of the female partner. From our findings, age plays a significant role in the eventual outcomes of controlled ovarian hyperstimulation. Much as controlled ovarian hyperstimulation may bypass the natural follicle recruitment, it is still limited to a certain extent by the quality of oocytes which are age dependant. Recommendations Work up for infertility should not be delayed for women in their thirties, as increasing age decreases the prognosis of assisted reproduction. Women should also be advised against delayed child bearing as the chances of success of assisted reproduction are also limited with increasing age .