Vitamin C supplementation in pregnancy.

Area of Science:

• Obstetrics and Gynecology
• Nutritional Science
• Clinical Trials and Evidence Synthesis

Background:

• Pregnancy complications like pre-eclampsia, intrauterine growth restriction, and maternal anemia may be reduced by Vitamin C supplementation.
• There is a need to evaluate the efficacy and safety of Vitamin C supplementation in pregnant women.

Purpose of the Study:

• To evaluate the effects of Vitamin C supplementation, alone or with other supplements, on pregnancy outcomes.
• To assess adverse events, side effects, and healthcare resource utilization associated with Vitamin C supplementation in pregnancy.

Main Methods:

• Searched the Cochrane Pregnancy and Childbirth Group's Trials Register and reference lists.
• Included randomized or quasi-randomized controlled trials of Vitamin C supplementation in pregnant women, excluding multivitamins with Vitamin C or iron as the primary supplement.
• Two independent reviewers assessed trial inclusion, risk of bias, and extracted data.

Main Results:

• Twenty-nine trials involving 24,300 women were analyzed.
• No clear differences were observed for stillbirth, neonatal death, perinatal death, birthweight, intrauterine growth restriction, preterm birth, preterm PROM, term PROM, or clinical pre-eclampsia.
• Vitamin C supplementation reduced the risk of placental abruption (high quality evidence) and slightly increased gestational age at birth, but was associated with increased self-reported abdominal pain.

Conclusions:

• Current data do not support routine Vitamin C supplementation for preventing fetal/neonatal death, poor fetal growth, preterm birth, or pre-eclampsia.
• Further research is needed to clarify Vitamin C's role in preventing placental abruption and prelabour rupture of membranes.
• No convincing evidence of other significant benefits or harms from Vitamin C supplementation in pregnancy was found.