The Effect of Adding Vaginal Progesterone to Oral Omega-3 Fatty Acids on the Birth Weight of Constitutionally Small for Gestational Age Fetuses: A Randomized Clinical Trial

Aim: To investigate the effectiveness of adding vaginal progesterone to oral omega-3 fatty acids on the birth weight of constitutionally small for gestational age fetuses (SGA). Materials and Methods: The study was a randomized clinical trial conducted from May 2020 to June 2022 at Assiut Woman's Health Hospital, Egypt including pregnant women in singleton fetuses (26-28 weeks) whose pregnancy was associated with constitutionally SGA fetuses. The eligible women were randomized to either group I (oral omega-3 fatty acids group) or group II (vaginal progesterone plus oral omega-3 fatty acids group); given daily till delivery. The primary outcome was the mean birth weight (gm) at the time of delivery. The data were analyzed using an unpaired t-test and the Chi-square test. Results: Eighty women were divided equally into two groups. There was a statistically significant increase in the mean birth weight (gm) at the time of delivery in group II in comparison to group I (1762.74 ± 80.06 vs. 1852.94 ± 71.71, receptively; p=0.000 ). The mean of uterine artery resistant index (RI) has a statistically significant decrease at 32 weeks and 36 weeks ( p value=0.000 ) and the mean of umbilical artery RI has a statistically significant decrease at 36 weeks ( p value=0.001 ) in group II. Conclusion : Adding vaginal progesterone to oral omega-3 fatty acids is superior to oral omega-3 fatty acids alone in increasing the birth weight of constitutionally SGA fetuses when given from 26-28 weeks gestation till delivery. The improvement of the feto-maternal blood flow may be behind the treatment result.