Wiley Logo Women with a short cervix are believed to be under a severe threat of experiencing preterm birth. A recent study claims that progesterone can decrease the rate of preterm birth before the 33rd week of pregnancy by 45 percent among women at risk. Infants born to women receiving progesterone seem to face a lower risk of developing respiratory distress syndrome.

While conducting the study, 458 women with a short cervix of 10-20 millimeters were randomly selected to either receive a vaginal gel progesterone preparation or a placebo between the 19th and 23rd week of pregnancy. Progesterone treatment was supposedly linked with a lower rate of preterm delivery at less than 33 weeks. Decline in the rate of preterm delivery was reported by 8.9 percent in the progesterone group and 16.1 percent in the placebo group.

“Our study demonstrates that progesterone gel reduces the rate of early preterm delivery—less than 33 weeks— in women with a short cervix. Women with a short cervix can be identified through routine ultrasound screening. Once identified, they could be offered treatment with progesterone,” explained Roberto Romero, M.D., program head for Perinatology Research and Obstetrics and chief of the Perinatology Research Branch.

Progesterone apparently maintains pregnancy and a short cervix is a sign of a possible shortage of the naturally occurring hormone. Giving progesterone to women with a short cervix presumably prolongs pregnancy. Variations in the rate of preterm birth appeared in births before 28 and 35 weeks of pregnancy. Three percent newborns of women provided with progesterone and 7.6 percent from the placebo group reportedly had a lower rate of respiratory distress syndrome.

The study is published online in the journal Ultrasound in Obstetrics and Gynecology.