Does first polar body morphology predict oocyte performance during ICSI treatment?

Abstract

Purpose To gain insight into the morphology of the first polar body (1 PB) in ICSI patients and to explore whether it could predict mature oocyte viability and performance in this setting. Methods Seventy two consecutive women planned to perform ICSI treatment were prospectively recruited for this study. All oocytes retrieved underwent evaluation for nuclear maturity and accurate assessment of 1 PB morphology. MII oocytes were cultured in separate groups in each woman in accordance with two different categories of 1 PB morphology. Category A included normal intact round or ovoid 1 PB and category B included abnormal fragmented 1 PB. Each oocyte was followed throughout fertilization, embryo cleavage and embryo transfer. Cycles that reached embryo transfer, were divided into three groups in accordance with 1 PB morphology. Group I included only category A 1 PB embryos, group II included categories A and B 1 PB embryos, whereas group III included only category B 1 PB embryos. Results A total of 687 oocytes were aspirated and 553 MII oocytes underwent ICSI leading to 410 zygotes showing normal fertilization on day one. Three hundred ninety seven embryos cleaved on day two and a total of 176 embryos were replaced into the uterus. Clinical implantation and pregnancy rates were significantly correlated with the morphology of the 1 PB corresponding to 31%, 9% and 2% and 61%, 24% and 5%, in groups I, II and III respectively. Conclusions Our findings demonstrate that 1 PB morphology is related to mature oocyte viability and it has the potential to predict oocyte performance and pregnancy achievement in infertile women undergoing ICSI treatment.

First polar body morphology affects potential development of porcine parthenogenetic embryo in vitro

“…Previous studies have demonstrated that PB1 morphology is related to mature oocyte viability, and have the potential to predict oocyte performance and pregnancy achievement in infertile women undergoing intracytoplasmic sperm injection (ICSI) treatment (Younis et al , 2009). Recently, it has also been found that PB1 morphology may reflect the development competence of oocytes in vitro (Rose & Laky, 2013).…”

“…Oocytes with intact or smooth PB1 can generate better second-day embryos, greater blastocyst yields, and increased pregnancy and implantation rates (Younis et al , 2009; Rose & Laky, 2013). It has also been found that embryos in the intact or smooth PB1 group show increased rate of blastocyst formation compared with the fragmented PB1 group ( P < 0.05) (Navarro et al , 2009; Rose & Laky, 2013).…”

“…Several researchers have questioned the possible correlation between the normal development of PB1 morphology to fertilization rate, cleavage rate, embryo quality, and blastocyst formation (Scott et al , 2007; Younis et al , 2009; Navarro et al , 2009; Rose & Laky, 2013). Therefore, these indicators cannot ensure full-term development of matured oocytes.…”

Relationship of polar bodies morphology to embryo quality and pregnancy outcome

“…During maturation and fertilization, the human oocyte releases the first and second polar body (PB 1 and PB 2 ), respectively, via two asymmetric divisions (meiosis). The relationship between PBs and oocytes has attracted much attention because of the homology of their chromatin with the oocytes (Munné et al, 1995;Ebner et al, 1999Ebner et al, , 2000Ebner et al, , 2002Durban et al, 2001;Verlinsky 2003;Fancsovits et al, 2006;Younis et al, 2009;Halvaei et al, 2011;Reich et al, 2011). However, most research has focused on PB 1 and controversy still exists (Munné et al, 1995;Ebner et al, 1999Ebner et al, , 2000Ebner et al, , 2002Durban et al, 2001;Verlinsky 2003;Fancsovits et al, 2006;Younis et al, 2009;Halvaei et al, 2011;Reich et al, 2011).…”

Influence of the uterine environment on the development of in vitro-produced equine embryos

“…Earlier studies involving intrauterine transfer of small numbers of in vivo-derived horse embryos were not very successful (Allen & Rowson 1975, Ball et al 1989, Weber et al 1993, but 'premature intrauterine transfer' with large numbers of day 2-3 IVP horse embryos has not been described previously. In this latter respect, while it is common practice to culture embryos to the blastocyst stage before intrauterine transfer in most domestic species, in human medicine, premature intrauterine transfer of day 2 and 3 IVP embryos is a routine procedure that yields good results (Younis et al 2009) and circumvents the potential downsides of prolonged in vitro culture or the difficulty of transferring early embryos to the oviduct. Currently, blastocyst rates of 25-35% can be obtained after ICSI and in vitro culture of cleaved horse embryos (Hinrichs 2010).…”