A retrospective study on analyzing the role of oocyte maturation arrest as a causative factor for infertility in unexplained infertility

Background: Birth is often referred to as “the miracle of life” and very rightly so since successful pregnancy represents a complex, a highly coordinated succession of biological processes. In this regard, it is remarkable that pregnancy ever occurs at all. Infertility is a reproductive system disorder affecting 10.7% to 15.5% of couples. Highly heterogeneous in etiology. Investigating the cause is necessary for guiding treatment options. Aim of the study was to determine the percentage of immature oocytes retrieved at the metaphase 1 stage and germinal vesicle stage and its outcome.Methods: Total 30 cases were included for this retrospective analysis of data done at ARC fertility center, Saveetha Medical College. This study analyzed the data of patients with unexplained infertility who underwent ICSI centers (affiliated to Saveetha University) meeting inclusion criteria and willing to participate in the study.Results: The mean number of fertilized oocytes among those with more than 25% immature oocyte proportion was 1.18 while among those with less than 25% immature oocyte proportion was 4.13. The chance of fertilization of the oocyte increases when the percentage of immature oocyte was less than or equal to 25%. The association was found to be statistically significant with p-value <0.05.Conclusions: Thus, some intrinsic oocyte factor could be involved in causing maturation arrest in such couples and resulting in multiple failed IVF cycles.so this oocyte factor could be a major cause in many cases of unexplained infertility.

Fertilization and pregnancy potential of immature oocytes from stimulated intracytoplasmic sperm injection cycles / 대한생식의학회지

OBJECTIVE: We evaluated the fertilization potential of immature oocytes obtained from controlled ovarian hyperstimulation cycles of patients undergoing ICSI. METHODS: We retrospectively analyzed 463 ICSI cycles containing at least one immature oocyte at oocyte denudation. ICSI was performed on mature oocytes at oocyte denudation (metaphase-II [MII] oocytes) and the oocytes that extruded the first polar body between oocyte denudation and ICSI (MI-MII oocytes). Fertilization and early embryonic development were compared between MII and MI-MII oocytes. To investigate the pregnancy potential of MI-MII oocytes, the pregnancy outcome was analyzed in 24 ICSI cycles containing only immature oocytes at retrieval. RESULTS: The fertilization rate of MI-MII oocytes (37.0%) was significantly lower than that of MII oocytes (72.3%). The rates of delayed embryos and damaged embryos did not significantly differ. Eighty-one immature oocytes were retrieved in 24 cycles that retrieved only immature oocytes and 61 (75.3%) of them were in the MI stage. ICSI was performed on 36 oocytes (59.0%) that extruded the first polar body before ICSI and nine MI-MII oocytes (25.0%) were fertilized. Embryo transfers were performed in five cycles. Pregnancy was observed in one cycle, but it ended in biochemical pregnancy. CONCLUSION: In ICSI cycles, oocytes that extruded the first polar body between denudation and ICSI can be used as a source of oocytes for sperm injection. However, their fertilization and pregnancy potential are lower than that of mature oocytes. Therefore, ovarian stimulation should be performed carefully for mature oocytes obtained at retrieval, especially in cycles with a small number of retrieved oocytes.

A Simple Technique for Immature Oocytes Rescue by In-vitro-maturation Culture in Controlled Ovarian Hyperstimulation Cycles / 中山大学学报(医学科学版)

[Objective]To evaluate the role of mature cumulus cells from oocyte-cumulus complex(OCC)in in-vitro maturation(IVM)and establish a new culture technique which is convenient to carry out.[Methods]The cumulus cells of OCC were cut off and dispersed by 1 mL syringe.The cumulus cells were co-cultured with the immature oocytes retrieved from the COH cycles after they adherent to the bottom of the dish.The immature oocytes were experienced IVM procedures in different culture media.They were divided into 3 groups(the oocytes at germinal vesicle stage from one woman were allotted to the same group randomly).Group 1(solution A):basic culture medium+human follicular fluid(hFF);Group 2(solution B):solution A+ cumulus cells(OCC);Group 3(solution C):solution A+ OCC+ follicle stimulating hormone(FSH)+ epidermal growth factor (EGF).Then,the maturation rate,fertilization rate and formation rate of available embryo were observed.[Results]In 113 treatment cycles,298 immature oocytes were performed IVM with solution A,B,and C.The difference for 24 hour maturation rates among 3 groups wag statistically significant(A:45.2%,B:61.7%,C:78.2%,P＜0.05).There was no statistical difference for 25～48 hour maturation rates and normal fertilization rates of mature oocytes.The differences of cleavage rates and rescued embryo rates between group 1 and 2,group 1 and 3 were statistically significant(P＜0.05).The formation rates of available embryo showed an increasing trend from group 1,2,to 3.[Conclusion]After being dispersed by simply beat upon with syringe and adherent culture,the mature cumulus eells from mature OCCs in COH cycles,together with growth factors in the follicular fluid or extraneously supplemented,could promote the IVM of immature oocyte.