ORIGINAL RESEARCH

Asthma During Pregnancy Mitchell P. Dombrowski, MD, Michael Schatz, MD, Robert Wise, MD, Valerija Momirova, MS, Mark Landon, MD, William Mabie, MD, Roger B. Newman, MD, Donald McNellis, MD, John C. Hauth, MD, Marshall Lindheimer, MD, Steve N. Caritis, MD, Kenneth J. Leveno, MD, Paul Meis, MD, Menachem Miodovnik, MD, Ronald J. Wapner, MD, Richard H. Paul, MD, Michael W. Varner, MD, Mary Jo O’Sullivan, MD, Gary R. Thurnau, MD, and Deborah L. Conway, MD, for the National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network and The National Heart, Lung, and Blood Institute OBJECTIVE: To determine neonatal and maternal outcomes stratified by asthma severity during pregnancy by using the 1993 National Asthma Education Program Working Group on Asthma and Pregnancy definitions of asthma severity. The primary hypothesis was that moderate or severe asthmatics would have an increased incidence of delivery at