Effect of Obesity on Oocyte and Embryo Quality in Women Undergoing in Vitro Fertilization: A Retrospective Study

Abstract

The effects of obesity are not restricted to a single aspect of female reproduction but are manifested at several levels: altered levels of hypothalamic gonadotropins, anovulation, altered steroid production, reduced conception rates, longer times to conception, increased miscarriage rates, increased risk of many pregnancy complications ranging from hypertension to preterm birth, and increased incidence of fetal abnormalities. The rising incidence of obesity coupled with its detrimental effects on fertility has led to greater numbers of overweight and obese women utilizing assisted reproduction technologies (ART), such as in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). Obesity may lengthen the duration of ovulation induction, increase the gonadotrophin dose required to achieve sufficient stimulation response, decrease the peak of estradiol levels on the day of HCG administration, decreased the number of mature follicles and number of oocytes retrieved. Moreover, obesity may have a negative impact on oocyte and embryo quality. Thus, fertilization, embryo transfer, implantation and pregnancy rates have been usually found to be low in obese patients in many studies. In addition, oocyte retrieval and embryo transfer procedures can be difficult due to obesity itself. Finally, miscarriage rate is found to be high.