The effect of betamethasone administration to pregnant women on maternal serum indicators of infection

Objective: To study the effect of betamethasone therapy on maternal white blood cell count, C-reactive protein and erythrocyte sedimentation rate in women at high risk for preterm delivery. Study design: We included women at gestational age of 24 to 34 weeks who were treated by betamethasone for enhancement of fetal lung maturity, because of imminent preterm labor with intact membranes. Blood tests for white blood cell and differential count, C-reactive protein and erythrocyte sedimentation rate were drawn before betamethasone injection, 2 hours after, and then every 24 hours for three days. Results: 105 women were included. The mean white blood cell count increased by 33 % on day one, and returned to baseline level three days after the first injection of betamethasone. A significant rise in neutrophil count, and drop in lymphocyte count was noted as early as two hours after the first injection and lasted for two days. Mean C-reactive protein and erythrocyte sedimentation rate levels were not changed significantly by betamethasone treatment. Conclusions: Antenatal betamethasone therapy causes a transient increase in maternal leukocyte count but has no effect on serum C-reactive protein and erythrocyte sedimentation rate. This information is relevant for preterm pregnant women who are at high risk for chorioamnionitis.