Cumulative continuing pregnancy rate of women with repeated implantation failure

Abstract

Objective Recurrent implantation failure (RIF) refers to failure of implantation of at least four embryos or two blastocysts in repeated cycles of in‐vitro fertilisation (IVF). However the pregnancy outcomes of women with RIF were not well defined. We aim to report the pregnancy outcomes of the second IVF cycle in women with RIF following the first IVF cycle. Design This was a retrospective review. Methods All women undergoing the second IVF cycle from August 2008 to December 2016 in a university affiliated hospital were reviewed. Women who returned for the second cycle were included. They were <43 years old and body mass index <30 kg/m2. Those who had undergone pre‐implantation genetic testing or embryo or oocyte donation were excluded. Results In 1189 women who had undergone the second IVF cycle during the period, 200 women met the criteria of RIF in the first cycle. The mean age of the RIF group and non‐RIF group were 36.9 ± 2.8 years and 36.5 ± 3.1 years respectively. The women in the RIF group had a longer duration of infertility (5.5 ± 2.7 years versus 4.7 ± 2.7 years respectively, P < 0.005) and lower FSH dosage used (2470 ± 930 IU and 2740 ± 1510 respectively, P = 0.016) but more total number of embryos (4 (0–13) versus 3 (0–15) respectively, P < 0.005) when compared with those in the non‐RIF group. Despite that, there were no significant differences in on‐going pregnancy rate in the stimulated IVF cycle (23.0% per transfer in the RIF group versus 24.1% per transfer in the non‐RIF group, P = 0.520) and the cumulative on‐going pregnancy rate per one stimulation cycle (38.0% in the RIF group versus 36.5% in the non‐RIF group, P = 0.773). By stratifying the results according to the number of oocytes retrieved in the first cycle, having >= 20 oocytes retrieved in the first cycles was associated with higher cumulative pregnancy rate in the subsequent cycles (55.0% in >= 20 oocytes retrieved, versus 41.8% in 10–19 oocytes retrieved and versus 34.2% in <10 oocytes retrieved, P = 0.020). Conclusion Women with RIF following the first IVF cycle had the cumulative on‐going pregnancy of the second IVF cycle similar to those who did not have RIF in the first cycle. The number of oocytes retrieved in the first IVF cycle may be a better prognostic indicator in subsequent cycles. These women should be counselled accordingly.