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Identification of factors related to fertilization failure in in vitro fertilization-embryo transfer.

OBJECTIVES
To investigate the possible factors relevant to fertilization failure in in vitro fertilization-embryo transfer (IVF-ET).


METHODS
The medical records of 4 205 infertile patients undergoing IVF-ET treatment at the Reproductive Medicine Center, Xiangya Hospital, Central South University from January 2016 to December 2017 were collected. The patients were divided into a complete fertilization failure group, a low fertilization rate group, and a control group based on fertilization rate. We examined the associations among the 3 groups in terms of female age, duration of infertility, duration of stimulation, gonadotropin (Gn) dosage, follicle-stimulating hormone (FSH) dosage, and total number of retrieved oocytes. According to theincidence factors, the patients were divided into a single female factor group, a single male factor group and a unisex factor group, and the correlation analysis of incidence factor among the 3 groups was performed. The patients were divided into a primary infertility and a secondary infertility in accordance with the type of infertility. We analyzed the correlation of infertility type among the three groups. Risk factors for complete fertilization failure and low fertilization rate in IVF-ET were obtained by stepwise multiple linear regression analysis.


RESULTS
Primary infertility, long infertility duration, total number of retrieved oocytes, and unisex factor were associated with completefertilization failure and low fertilization rate in IVF-ET (P<0.05), but female age, duration of stimulation, FSH dosage as well as Gn dosage were not correlated with complete fertilization failure and low fertilization rate in IVF-ET (P>0.05). Stepwise multiple linear regression analysis showed that the incidence factor, type of infertility, and infertility duration were independent influential factors for complete fertilization failure and low fertilization rate.


CONCLUSIONS
Complete fertilization failure and low fertilization rate in IVF-ET are related to duration of infertility, total number of retrieved oocytes, cause of onset, and type of infertility, but they are not relevant to female age, duration of stimulation, and Gn and FSH dosage.