Home Health Parents News Now Progesterone Can Only Prevent Some Premature Labors Progesterone Can Only Prevent Some Premature Labors By Holly Lebowitz Rossi October 23, 2012 Advertisement Save Pin FB More Tweet Mail Email iphone Send Text Message Print shutterstock_111643082 29972 Now a new randomized double-blinded trial, published online in The American Journal of Obstetrics & Gynecology, reports that progesterone in its injected form does not work for a much larger risk group: the 10 percent of women with a cervix shorter than 30 millimeters. These women have about the same risk of having a preterm birth — around 25 percent — as those who have already had one. "The study emphasizes that because progesterone works for one group at risk for preterm birth doesn't mean that it can automatically be extended to others," said the lead author of the study, Dr. William A. Grobman, a professor of obstetrics and gynecology at Northwestern. Researchers randomly assigned 657 women to a weekly injection of a form of progesterone or to a placebo shot. All were pregnant for the first time with a single baby, and each had a cervical length of less than 30 millimeters at 16 to 22 weeks' gestation. The women were followed through discharge from the hospital. The scientists were unable to find any significant differences in birth outcomes between the two groups. Of those who took the progesterone, 25.1 percent delivered prematurely (at less than 37 weeks) and so did 24.2 percent of those on the placebo. Image: Pregnant belly, via Shutterstock By Holly Lebowitz Rossi Save Pin FB More Tweet Mail Email iphone Send Text Message Print Comments Add a Comment Be the first to comment! Advertisement Close this dialog window Add a comment Progesterone Can Only Prevent Some Premature Labors Add your comment... Cancel Submit Success! Thanks for adding your feedback.