Comparação entre diferentes intervalos de cultivo após descongelamento de embriões, em estágio de clivagem, e sua influência nas taxas de sucesso de tratamento com técnicas de reprodução assistida

Abstract

ABSTRACT

Objective: evaluate whether selecting embryos for transfer after prolonged culture after thaw (18-24 hours) has better pregnancy rates than selecting embryos for transfer after short culture after thaw (2-5 hours). Design: Double-blinded, randomized, controlled trial

Setting: Private IVF center

Patient(s): A total of 388 patients submitted to ART treatment who had embryos frozen on day-2 and subsequently transferred. All patients received the same endometrial priming with estradiol valerate followed by vaginal progesterone. Intervention(s): Randomization for Frozen embryo transfer 2-5 hours after thaw (Group D2) or 18-24 hours after thaw (Group D2/D3). Main Outcome Measure(s): Ongoing pregnancy rate (OPR) at 20 weeks' gestation per embryo transfer Results: A total of 179 patients had embryos transferred 2-5 hours after thaw and 209 patients had embryos transferred 18-24 hours after thaw. The mean age in group D2 was 36±4.4 and 36±5.4 in group D2/D3. Ongoing pregnancy rate was 28% and 33.5% (p=0.2) for groups D2 and D2/D3, respectively. Conclusions: These results suggest that increasing the culture time of embryos in one day to improve selection before transfer does not increase ongoing pregnancy rate.

Clinical Trial Registration Number: NCT03381001

Key Words: Vitrification, Frozen embryo transfer, embryo culture, Cleavage stage, ART