Effect of metformin on maternal and neonatal outcomes in pregnant obese non-diabetic women: A meta-analysis|
Elmaraez, Ahmed; Abushouk, Abdelrahman Ibrahim; Emara, Amany; Elshahar, Omar; Ahmed, Hussien & Mostafa, Magdy I.
Background: Metformin reduces maternal and neonatal weight gain in gestational
diabetes mellitus; however, this effect is poorly investigated in non-diabetic women.
Objective: We performed this meta-analysis to investigate the effect of metformin
intake during pregnancy on maternal and neonatal outcomes in obese non-diabetic
Materials and Methods: We searched Medline, EMBASE, and Cochrane
CENTRAL for eligible randomized controlled trials addressing the efficacy of
metformin in pregnant obese non-diabetic women. Data were extracted and analyzed
using RevMan software (Version 5.3). Neonatal birth weight was the key outcome.
Secondary outcomes included maternal weight gain, the incidence of preeclampsia,
and neonatal adverse effects (miscarriage, stillbirth and congenital anomalies).
Results: Pooled data from two RCTs (n=843) showed that metformin caused a
significant reduction in maternal gestational weight gain (MD-1.35, 95% CI: [2.08, -0.630]), compared to placebo. The summary effect-estimate did not favor either of
the two groups in terms of reduction of neonatal birth weight Z score (MD-0.09,
95% CI: [0.23, 0.06]). Metformin was associated with 41% reduction in the risk of
preeclampsia; however, this reduction was not statistically significant [RR 0.59,
95% CI: [0.03, 11.46]). None of the neonatal adverse events including stillbirth [RR
1.14, 95% CI: 0.42, 3.10]) and congenital anomalies (RR= 1.36, 95% CI: [0.58,
3.21]) differed significantly between the two groups.
Conclusion: For obese pregnant women, metformin could decrease gestational
weight gain with no significant reduction in neonatal birth weight. In light of the
current evidence, metformin should not be used to prevent poor pregnancy outcomes
in obese non-diabetic women.
Birth weight; Diabetes mellitus; Metformin; Obesity; Pregnancy.