Background: Low consumption of fish has been linked to higher percentage of preterm deliveries and DHA supplementation noted to result in longer gestation (G) and increased birth weight (BW), yet other studies have failed to show such an association. Aim: To determine whether in multiparous mothers, DHA supplementation during pregnancy
would affect G length and infants’ BW.
Materials and Methods: Of 60 mothers aged 20 - 35y in ≥3rd pregnancy (~40% in 5th -7th pregnancy) 30 randomly assigned to receive DHA 400mg/day (Martek Biosciences Corp, Solgar, Leonia NY) from 12th week gestation. Nutritional intake with emphasis on amount & type of oil and fish consumed, recorded. G length and BW of current pregnancy compared between groups and within groups to previous pregnancies (total no. previous pregnancies; 133 in DHA group, 137 in control group).
Results: Mean BW at current pregnancy did not differ between DHA and non-supplemented
group (3.34±0.50 vs. 3.31±0.50 p= 0.08). Within each group BW increased with parity but degree of increase did not differ between DHA(+ ) and non-supplemented group. Although mean G length in current pregnancy did not differ between DHA and non- supplemented group (40±1.66 vs. 39.9±0.92 weeks p=0.77) the number of women giving birth post-term was higher in the DHA supplemented group (30% vs.10% of mothers p=0.057). Of 6 mothers in the DHA (+) group, in ≥6th pregnancy, 5 gave birth post - term (none had previously given birth post–term), as compared to only 1of 6 mothers in≥6th pregnancy in non-supplemented group (in this mother all previous births had been post–term) ; Mean G length in ≥6th pregnancy mothers 41.33±0.816 in DHA(+) vs. 39.83±0.98 weeks in non–supplemented group p=0.016.
Conclusions:- In multiparous mothers, DHA supplementation during pregnancy does not affect infants’ birth weight. – In highly multiparous mothers DHA supplementation may result in lengthening of gestational period.
