Factors associated with oocyte recovery rates during in-vitro fertilization among Nigerian women

the availability of oocytes is fundamental to in vitro fertilization (IVF). The factors associated with optimal or suboptimal oocyte recovery rates (ORR) in low-resource settings are not well known. This study aimed to determine the factors associated with ORR by comparing demographic and IVF cycle data of women undergoing IVF in our Centre.

this was a prospective study of 110 infertile women undergoing IVF at Nisa Premier Hospital, Abuja Nigeria, from October 2020 to September 2021. All women had reached the stage of oocyte retrieval or further, after receiving ovarian stimulation with our routine protocols. Treatment was monitored by serial transvaginal ultrasonography. The oocyte retrieval procedures were performed under conscious sedation, 36 hours after the ovulatory trigger. Optimal ORR was when eggs were obtained from at least 80% of follicles punctured. Sub-optimal ORR was when it was less than 80%. Data analyses utilized SPSS statistical software and a p-value of < 0.05 was considered significant.

the mean age of all women was 34.1±4.9 years. Sixty-nine women (62.7%) had sub-optimal ORR while 41 (37.3%) had optimal ORR. Six women (5.5%) had no oocytes retrieved. Significantly more women with sub-optimal ORR were obese (70.6 vs 29.4%) and had higher follicle-stimulating hormone (FSH) levels (8.11 vs 6.34 miu/ml), p-value- 0.039. Women with sub-optimal ORR had higher mean prolactin levels (17.10 ± 13.93 miu/ml) than women with optimal ORR 11.43 ± 6.65 miu/ml), p-value- 0.019). Significantly more oocytes (5.99 vs 10.37, p-value 0.001), and MII oocytes (5.78 vs 7.56, p-value 0.035) were retrieved in women with optimal than sub-optimal ORR. The duration of stimulation, total amounts of gonadotropins administered, and fertilized oocytes were not significantly different among both groups (p-value >0.05).

this study has shown the factors associated with ORR in our setting to be basal FSH, prolactin, and obesity.