Berkowitz Richard L, Montalto Donna
From the Department of Obstetrics and Gynecology, Columbia University Medical Center, New York, New York; and the American College of Obstetricians and Gynecologists, District II, Albany, New York.
Obstet Gynecol. 2010 Oct;116(4):810-814. doi: 10.1097/AOG.0b013e3181f0bda9.