The effect of maternal anemia on maternal and neonatal outcomes in twin pregnancies

Objective: The objective of this study is to investigate the effect of second trimester anemia on maternal and perinatal outcomes in twin pregnancies. Methods: A retrospective population-based study was conducted, comparing maternal and neonatal outcomes in women carrying twins, with second trimester anemia (defined as hemoglobin <10 g/dl) to those without anemia (defined as hemoglobin > or equal to 10 g/dl). Deliveries occurred in a tertiary medical center in 2013. Results: During the study period, there were 307 twin deliveries. Hemoglobin levels were available for 247 (80.4%) twins; 66 (26.7%) of these had anemia (<10 g/dl) during the second trimester. Women with second trimester anemia had a higher parity (p = 0.03), and needed more blood transfusions than those with hemoglobin level > or equal to 10 g/dl (OR = 1.6; 95% CI 1.11-2.43, p<0.001). No significant differences were noted between the groups regarding other obstetrical outcomes or regarding perinatal outcomes. Conclusion: Second trimester anemia in women carrying twins is associated with a high parity and increases the risk for blood transfusions. However, in our population, maternal anemia in twin gestations does not increase the risk for adverse perinatal outcome.