Multivitamin use and adverse birth outcomes in high-income countries: a systematic review and meta-analysis

Background In high-income countries, a healthy diet is widely accessible. However, a change toward a poor-quality diet with a low nutritional value in high-income countries has led to an inadequate vitamin intake during pregnancy. Objective We conducted a systematic review and meta-analysis to evaluate the association between multivitamin use among women in high-income countries and the risk of adverse birth outcomes (preterm birth [primary...