The association between fatty acid index and in vitro fertilization outcomes.

Purpose: Fatty acids have been shown to play an important role in oocyte competence and early implantation of the embryo. Our hypothesis-generating study sought to determine if individual fatty acids expressed as a percentage of total erythrocyte fatty acids are associated with embryo quality and other in vitro fertilization (IVF) outcomes.
Methods: This was a prospective cohort study at an academic fertility center. Sixty women undergoing their first IVF cycle were recruited. Serum measurements of 22 fatty acids were obtained. We calculated each fatty acid as a percentage of total fatty acids, defined as the index for that individual fatty acid.
Results: Omega-3 index had no correlation with IVF outcomes. A negative correlation was found between the trans fatty acid index, elaidic acid (EA), and IVF outcomes, including fertilization rate (r = - 0.261, p = 0.04), blastocyst conversion rate (r = - 0.41, p = 0.001), and number of usable blastocysts and embryos (r = - 0.411, p = 0.001). There was no correlation between EA index and number of oocytes retrieved, embryo grade, or clinical pregnancy. No consistent correlations were observed with the additional fatty acids analyzed.
Conclusions: No correlation was observed between omega-3 index and IVF outcomes. Elevated erythrocyte EA index, the major trans fatty acid commonly consumed in hydrogenated oils, margarine, and fried foods, was negatively correlated with number of usable blastocysts and embryos, blastocyst conversion, and fertilization rate. Our findings suggest preliminary evidence that trans fat may be negatively associated with IVF outcomes.