Comparison of short and long co-incubation time of gametes for in vitro fertilization

Abstract

Background: The short and long co-incubation time of gametes for in vitro fertilization are still debatable issues. This study aims to investigate the effects of short and long co-incubation time of gametes on fertilization, polyspermy, embryonic developmental potential, and clinical outcomes.Methods: Sixty-five patients undergoing IVF treatment were invited to participate in the study between May 2017 and March 2019. Ovarian hyperstimulation was prescribed and oocytes were obtained by trans-vaginal aspiration under ultrasound guidance. Sibling oocytes were randomly allocated to short co-incubation for 4 hours (Group I) in 352 oocytes and long co-incubation for 16-18 hours in 363 oocytes (Group II). Rescue ICSI was carried out if total fertilization failure was documented. Fertilization, embryonic development, and pregnancy outcomes were determined.Results: No significant differences between short and long co-incubation were found in fertilization, polyspermy, cleavage, blastocyst, implantation, clinical pregnancy, and live birth rates.Conclusions: The present study showed that short co-incubation of gametes had no significant difference in fertilization, polyspermy, embryo development, and pregnancy outcomes when compared to long co-incubation. The short co-incubation with early cumulus cell removal and rescue ICSI may have the potential to help a couple who had total fertilization failure.

Brief and long co-incubation of sperm and oocytes for in vitro fertilization: a meta-analysis of randomized controlled trials

“…Exclusion criteria: use of donor eggs/sperm; an abnormal uterine cavity shown on hysterosalpingogram or hysteroscopy; hydrosalpinges without treatment; endometrial thickness < 8 mm on day of hCG; severe oligospermia (total number of motile sperm < 0.1 million) or normal morphology < 5%; fertilization failure or fertilization rate < 30% for conventional insemination in the past; any risk of ovarian hyperstimulation syndrome (OHSS); blastocyst transfer; and natural cycles or mild stimulation protocols (freeze all strategy). Pongsuthirak (2019) [ 17 ] Inclusion criteria: patients with tubal disease, endometriosis, ovulatory dysfunction, unexplained infertility; aged 20–38 years; at least 6 retrieved oocytes and normal semen parameters. Coskun et al (1998) [ 18 ] Inclusion criteria: patients with tubal disease, unexplained infertility, male factor, endometriosis, polycystic ovary syndrome.…”

“…However, the result has been controversial because the trials involved in study were low quality and small sample sizes, and only one trial reported the live birth rate [ 12 ]. Furthermore, more and more studies found no such advantage following brief incubation when compared with long-term incubation [ 13 , 14 ].…”