Effects of cumulus cell removal time during in vitro fertilization on embryo quality and pregnancy outcomes: a prospective randomized sibling-oocyte study.

Na Guo,Qun Liu,Hua Zhao,Xinling Ren,Fei Yang,Yufeng Li,Jihui Ai

doi:10.1186/s12958-016-0151-3

Abstract

BackgroundTo investigate whether cumulus cell removal after a 3 h co-incubation of gametes can affect the outcomes of in vitro fertilization.MethodsA prospective randomized sibling-oocyte study was performed in which sibling oocytes obtained from each patient were randomly assigned to either a 3 h or 20 h group (cumulus cells removed at 3 h or 20 h after insemination, respectively). Same origin embryos (either 3 h or 20 h) were transferred. The study participants were patients < 38 years old and with infertility due to tubal factors. The study outcomes included fertilization, embryo quality, and birth status.ResultsThe study enrolled 172 patients, from whom 2275 oocytes were retrieved (1139 oocytes for the 3 h group and 1136 oocytes for the 20 h group). A total of 134 patients received embryo transfers (74 patients in the 3 h group and 60 patients in the 20 h group), and there were 54 live births (32 in the 3 h group and 22 in the 20 h group). When compared with patients in the 20 h group, patients in the 3 h group produced a larger number of optimal quality embryos, but had higher rates of polyspermy and low birth weight newborns. The two groups showed no differences in their rates of normal fertilization, pregnancy, and live birth.ConclusionsWhen compared with results obtained using a traditional cumulus cell removal protocol, early cumulus cell removal has both advantages and disadvantages. Further studies, and especially long-term outcome studies on newborns, need to be performed.Trial registrationCurrent controlled trial ChiCTR-OOC-15006878

Highlights

To investigate whether cumulus cell removal after a 3 h co-incubation of gametes can affect the outcomes of in vitro fertilization
In order to recognize unfertilized oocytes and perform intracytoplasmic sperm injection (ICSI) early on, oocytes have to be examined for the absence of a second polar body, and early cumulus cell removal can facilitate this examination [4]
An analysis on obstetric outcomes showed that low birth weight infants were more common in the 3 h group (Table 4)

Summary

Introduction

To investigate whether cumulus cell removal after a 3 h co-incubation of gametes can affect the outcomes of in vitro fertilization. Assisted reproductive technology, which includes several types of medical treatments, can improve the chance of pregnancy and a live birth. Even with in vitro fertilization (IVF), which has the highest success rate among all types of assisted reproductive technology, only ~ 50 % of women achieve pregnancy [1]. A rescue procedure, such as intracytoplasmic sperm injection (ICSI), can help improve the oocyte fertilization rate. It was previously shown that early ICSI can increase pregnancy rates and lead to better clinical outcomes [3]. Early cumulus cell removal can reduce the required co-incubation time between

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Discussion

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