ORIGINAL RESEARCH
Optimization of a single-embryo transfer in patients with good ovarian reserve
1 Samara State Medical University, Samara, Russia
2 IDK Medical Company, the Mother and Child group, Samara, Russia
Correspondence should be addressed: Natalya V. Saraeva
Vrubelya, 15–131, Samara, 443086; moc.liamg@anikhcizuk
Compliance with ethical standards: the study was approved by the Ethics Committee of Samara State Medical University (Protocol 194 dated September 12, 2018). Informed consent was obtained from all study participants.
Acknowledgements: the authors thank Komarova MV, PhD Biol., Associate Professor of Samara National Research University, for her help with the statistical analysis.
Author contribution: all authors equally contributed to the study and manuscript preparation.
Due to refinements of assisted reproductive technology, the number of multiple pregnancies has increased substantially. Time-lapse microscopy (TLM) is a tool for selecting quality embryos for transfer. This study aimed to assess the outcomes of single-embryo transfer of autologous oocytes performed on day 5 of embryo incubation in a TLM-equipped system in patients with good ovarian reserve. The study was carried out in 208 infertile women with good ovarian reserve (over 8 oocytes retrieved). Single-embryo transfer following incubation in a TLM-equipped incubator was performed in 95 patients, who formed the main group; the control group consisted of 113 patients undergoing single-embryo transfer following a traditional culture and embryo selection procedure. We assessed the quality of transferred embryos, the rates of clinical pregnancy and pregnancy loss. Two subgroups were identified in each group of the participants: the 5SET subgroup (nonelective single-embryo transfer), which included 45 patients from the main group and 67 controls, and the 5еSET subgroup (elective single-embryo transfer), which consisted of 50 main group patients and 46 controls. The groups did not differ in terms of age, infertility factors and infertility duration. The quality of transferred embryos was excellent or good in all main group patients (100%); in the control group, the quality of transferred embryos was excellent or good in 93.8% of cases (р = 0.037). Clinical pregnancies were achieved in 64.2% of women in the main group and in 60.2% of controls (р = 0.65). Delivery rates were 54% and 51.1% in the 5eSET and 5SET subgroups of the main group, respectively (р = 0.940). For the control group, delivery rates were 54.4% and 34.3% in the 5eSET and 5SET subgroups, respectively (р = 0.052, Fisher exact test). Elective single-embryo transfer (5eSET) and the use of TLM increased the chance of pregnancy 2.17-fold (р = 0.01).
Keywords: IVF, assisted reproductive technology, single-embryo transfer, elective blastocyst transfer, time-lapse microscopy