Maternal Preconception Omega-6, Omega-3, and Omega-6:Omega-3 Intake and Uterine Artery Indices in Mid-Gestation.

Objective:  Maternal preconception diet influences pregnancy health and fetal outcomes. We examined the relationship between preconception fatty acid (FA) intake and uterine artery indices in mid-gestation in a large, heterogeneous cohort of nulliparous individuals.

Study design:  This is a secondary analysis of the nuMom2b (Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-be) study. Dietary ω-6 and ω-3 FA intake was assessed with food frequency questionnaires and uterine artery indices were obtained via Doppler studies in the second trimester. For our primary outcome of pulsatility index (PI) > 1.6, we compared proportions by each dichotomous FA exposure and tested differences with chi-square test.

Results:  For PI > 1.6, odds ratio for the unfavorable FA quartile compared with remaining quartiles for the exposures were 0.96 to 1.25, p = 0.157 (ω-6 FA); 0.97 to 1.26, p = 0.124 (ω-3 FA); 0.87 to 1.14, p = 1.00 (ω-6:ω-3 FA ratio).

Conclusion:  No significant associations between self-reported maternal preconception ω-6 and ω-3 FA intake and uterine artery Doppler indices measured during the second trimester were observed.

Key points: · Maternal diet impacts pregnancy health/fetal outcomes.. · ω-3 and ω-6 FA intake influences cardiovascular health.. · FA intake may affect blood flow to fetoplacental unit.. · Results are limited by inadequate adherence to dietary recommendations..