Twenty-three publications reporting on 11 RCTs were included in the review (5,272 participants, range 48 to 2,399 per trial). One trial was at a low risk of bias for all of the quality domains assessed; results for the other trials were variable.
In the subgroup of preschool children aged two to five years, scores of cognition were statistically significantly higher among those whose mothers had taken DHA (a specific omega-3 LC-PUFA) during pregnancy and lactation compared with those who had not (WMD 3.92, 95% CI 0.77 to 7.08; two RCTs; Ι²=0%). Among the other studies conducted during pregnancy and lactation, no other statistically significant differences between groups were found in relation to cognitive development of infants aged under 12 months (one RCT), toddlers aged 12 to 24 months (two RCTs) or school-age children aged five to 12 years (two RCTs). Among studies conducted during pregnancy only, no statistically significant differences between groups were found in relation to cognitive development of toddlers (one RCT), preschool children (one RCT) and school-age children (one RCT).
Among studies conducted during pregnancy and lactation, there were no statistically significant differences between groups in relation to motor development of infants (one RCT), toddlers (two RCT) or preschool children (one RCT). Similarly, no significant differences in motor development were observed between groups in studies conducted during pregnancy only (one RCT).
In studies performed during pregnancy only, no statistically significant differences were observed between groups in relation to language development of toddlers (one RCT) and preschool children (one RCT). Six of the eight visual outcome assessments reported by studies (five RCTs) demonstrated no significant differences between the treatment and control groups.
Further details of the results were reported in the review.