Does different BMI influence oocyte and embryo quality by inducing fatty acid in follicular fluid?

We aimed to assess the effects of obesity-related follicular fluid (FF) fatty acids (FAs) on the number and quality of oocytes, good embryo quality rate, and pregnancy rate.

This prospective cohort study was conducted on 105 infertile women under the age of 38, who underwent intracytoplasmic sperm injection (ICSI) from March 2015 to October 2015. They were grouped into three body mass index (BMI) categories. The fatty acids composition of the FF was analyzed by GC-MS head space method. We studied the FAs correlation with BMI and ICSI outcomes.

The distribution of fatty acids did not differ significantly in each BMI group, with the exception for stearic that was marginally significant (p=0.05). The mean number of mature oocytes did not differ significantly between the BMI groups, the percent of Metaphase II (MII) oocytes was inversely associated with the BMI (r_s=-0.21, p=0.03). Kruskal-Wallis test showed that the distribution of good quality embryos' percentages were different in at least two categories of studied BMI groups (p=0.009, p=0.02). The mean concentration of palmitic acid was higher in nonpregnant patients for all of the studied BMI classes (p=0.02, p=0.03, p=0.05), however, stearic (p<0.001) and linolenic acids (p=0.01) were higher in nonpregnant normal weight patients.

Differences in BMI are not associated with the fatty acid composition of the FF. The FF fatty acid possibly affects the outcome of ICSI through the achievement of clinical pregnancy. Therefore, it is essential to provide patients with nutritional counseling before they use assisted reproductive techniques.