Frozen Embryo Transfers in Sub-Saharan Africa: A Five-Year Retrospective Study at Nordica Fertility Centre, Lagos, Nigeria

Abstract

Background: Frozen Embryo Transfers (FET) have gained popularity in recent years as an alternative or complementary option to fresh embryo transfers in In Vitro Fertilization (IVF) cycles. FETs offer several benefits, such as lower cost versus repeat cycles, reduced stress, and better endometrial receptivity. FETs are also indicated in cases where fresh transfers have been shown to give subpar results, such as in polycystic ovary syndrome (PCOS) and endometriosis patients. However, the evidence on the comparative success rates of FETs and fresh transfers is inconclusive, and the practice of FETs is not widespread in Sub-Saharan Africa.

Objectives: To describe the socio-demographic characteristics, indications, trends and outcomes of FET cycles performed at Nordica Fertility Centre, Lagos, Nigeria, between 2018 and 2022.

Methodology: This was a retrospective study of all FET cycles performed at Nordica Fertility Centre, Lagos, Nigeria, from January 2018 to December 2022. Data on patient age, parity, infertility diagnosis, number of frozen embryos transferred, implantation rate, clinical pregnancy rate, live birth rate and complications were collected and analyzed using descriptive statistics and Chi-square tests were employed to assess the associations between categorical variables.

Results: A total of 444 FET cycles were performed during the study period with 290 (65.3%) being from own eggs and 154 (34.7%) from recipients. The patients' overall mean age was 39.2±5.8 years with mean age of 33.4±4.7 and 45.0±6.9 for own eggs and recipients respectively. Fifty-two (17.9%) patients transferred 1 embryo, 166 (57.2%) patients transferred 2 embryos and 72 (24.8%) transferred 3 embryos while 10 (6.5%) patients transferred 1 embryo, 101 (65.6%) patients transferred 2 embryos and 43 (27.9%) transferred 3 embryos from own eggs and recipients, respectively for the FET procedure. The findings show that there is a significant (p=0.02) difference in the proportion of patients that transferred 1, 2 or 3 embryos when own eggs and recipients are compared. Ninety-four (32.4%) FET cycles resulted in viable pregnancies (Positive) and 196 (67.6) FET cycles were unsuccessful (Negative) from own eggs. Forty-four (28.6%) FET cycles resulted in viable pregnancies (Positive) and 110 (71.4) FET cycles were unsuccessful (Negative) from recipients. The result shows that there is no significant difference in the proportions of Own eggs and recipients that had positive or negative outcome (p=0.41). The FET cycles using Own Eggs had a slightly higher success rate of approximately 32.41% compared to FET cycles using Donor eggs which had a success rate of approximately 28.57%. This study observed a notable increase in the number of FETs performed annually, reaching its peak in 2022. This trend aligns with global patterns reported by the Society for Assisted Reproductive Technology (SART), reflecting a growing acceptance and utilization of FET over time.

Conclusion: FET is a safe and effective option for IVF patients in Sub-Saharan Africa, with comparable success rates to fresh transfers and lower risk of complications. FET is especially indicated for patients with PCOS, endometriosis, and recurrent implantation failure.