Clinical live birth after transfer of non selected cleavage embryos from vitrified/thawed oocytes. when embryo cryopreservation is not an option

Abstract

To report the reproductive outcome of infertile patients who underwent intracytoplasmatic sperm injection (ICSI) with autologous vitrified/thawed oocytes from a previous assisted reproductive technique (ART) cycle. Retrospective cohort analysis. The study included 369 infertile patients (34.3 ± 3.0 years) who had vitrified surplus oocytes from previous ART cycles at our institution from September 2008 through May 2012. A total of 2114 oocytes were vitrified using the Cryotop method. ICSI was performed 2 hours after thawing. Embryos were cultured in sequential culture media GIVF-Plus, G1.5 Plus,G2.5Plus (Vitrolife, Gothenburg, Sweden).All embryos were transferred on Day3. Pregnancy was biochemically defined as a rising β-hCG titer and clinical pregnancy was confirmed by ultrasound at 6 weeks of gestation. Seventy nine couples(21.4%) proceeded to thaw surplus oocytes from previous ART treatment. A total of 460 oocytes were thawed. The mean number of thawed oocytes per patient was 5.8± 2.8. Survival rate was 91.5% (421/460). Fertilization rate was 66.7%.The mean number of transferred embryos was 2.4± 0.9, being 52.8% (103/195) good quality embryos. The pregnancy rate per transfer was 31.6 % (25/79). Pregnancy loss rate was 24% (6/25). We had 3 biochemical 3 clinical pregnancies. Live birth rate was 24.1% (19/79). Nineteen healthy children were born (1 triple, 1 double and 15 single deliveries). These results show that oocyte vitrification is a safe technique and a ready to use alternative for those infertile patients who do not wish to cryopreserve embryos due to religious or ethical issues.