States where midwives practice independently have lower rates of Cesareans deliveries

States that allow autonomous practice by certified nurse-midwives (CNMs) have a higher proportion of CNM-attended births as well as lower rates of cesarean sections, preterm births, and low birthweight infants, according to a study published today in Women's Health Issues. Women's Health Issues is the official journal of the Jacobs Institute of Women's Health, which is based at Milken Institute School of Public Health (Milken Institute SPH) at the George Washington University.

Authors Tony Yang of George Mason University and Laura Attanasio and Katy Kozhimannil of the University of Minnesota School of Public Health analyzed data on 12 million births from 2009 through 2011 reported by 50 states and the District of Columbia to the Centers for Disease Control and Prevention. They classified each state as either being subject to collaborative agreement, meaning CNMs must have physician supervision or contractual practice agreements in order to practice (28 states), or as having autonomous practice, in which no such agreements are required (22 states and the District of Columbia). The authors found that women giving birth in the states allowing independent midwifery practice had a 60 percent greater chance of having a certified nurse midwife as a birth attendant.

Past research has found that midwives are less likely than obstetricians to use interventions like labor induction and cesarean delivery that may have higher risks for women and infants when performed without definitive medical need. The authors of this study also found that women giving birth in the group of states allowing autonomous midwifery practice had 13 percent lower odds of cesarean delivery, 13 percent lower odds of preterm birth, and 11 percent lower odds of delivering low-birthweight babies when compared to women giving birth in the states with stricter requirements for CNM practice.

"Future policy efforts to enhance access to midwifery services may be beneficial to pregnancy outcomes and infant health," the authors conclude, adding that more midwife-assisted births could lead to better birth outcomes and lower costs. They note that cesarean deliveries not only come along with health risks but are approximately 50 percent more costly than vaginal deliveries.

The study, "State Scope of Practice Laws, Nurse-Midwifery Workforce, and Childbirth Procedures and Outcomes," has been published online ahead of print and will appear in the May/June issue of Women's Health Issues.