Fatty acids of follicular fluid phospholipids and triglycerides display distinct association with IVF outcomes

RESEARCH QUESTION: Are triglyceride fatty acids in the follicular fluid associated with either follicular fluid phospholipid fatty acids or IVF outcomes and, if so, how are they associated?

DESIGN: In a prospective cross-sectional study, 70 women undergoing intracytoplasmic sperm injection were recruited. Follicular fluid phospholipids and triglycerides were separated by thin-layer chromatography. Fatty acids were measured using gas-liquid chromatography and flame ionization detection system.

RESULTS: Significant differences in fatty acid composition were observed between follicular fluid phospholipid and triglyceride fractions. Phospholipid stearic acid and n-3 polyunsaturated fatty acids, particularly alpha-linolenic acid, were negatively associated with the number of mature oocytes and cleaved embryos, whereas arachidonic acid was in direct correlation with cleavage rate per IVF cycle (β = 0.325, P = 0.022). In the case of triglyceride fraction, total monounsaturated fatty acids, oleic acid in particular, displayed significantly positive associations with the number of oocytes (β = 0.261, P = 0.043) and embryos (β = 0.310, P = 0.018). Furthermore, cleavage rate correlated inversely with palmitic acid (β = -0.359, P = 0.007) and directly with pentadecanoic acid (β = 0.378, P = 0.005). Most of these associations, however, were not independent of predictive fatty acids belonging to phospholipid fraction, according to multivariate analysis.

CONCLUSIONS: Fatty acid compositions of phospholipid and triglyceride fractions from human follicular fluid differentially correlate with IVF cycle parameters.