Pregnant women who have had prior preterm births may avoid a subsequent early birth if given progestogens, which are natural or synthetic forms of progesterone, a female hormone that naturally increases during pregnancy, a Vanderbilt analysis shows.
Women who have had prior preterm births and are given progestogens while expecting a single child show some benefit from additional hormone, Vanderbilt researchers reported in a systematic review released on Thursday in Obstetrics & Gynecology, the official publication of the American College of Obstetricians and Gynecologists, commonly referred to as The Green Journal.
The researchers looked at 34 prior studies of women who were given progestogens for prior preterm births, multiple gestations, preterm labor, short cervix or other indications. Each study included 20 or more women who were given the medication by injection, orally or vaginally, and took place between January 1966 and October 2011.
The work was funded by the Agency for Healthcare Research and Quality (AHRQ).
In contrast, the researchers found progestogens don't seem to help prevent preterm labor in women carrying twins or triplets. And evidence supporting giving progestogens for all other uses is insufficient to guide clinical care.
The review provides valuable information, but more study is needed, said Frances E. Likis, DrPH, N.P., CNM, research assistant professor of Medicine and the lead author of the review. "While we know that women have progesterone levels that go up in early pregnancy and remain elevated, we still don't understand why giving extra progestogens would help them stay pregnant," she said. "The pharmaceutical effects are not well understood."
The United States has a very high preterm birth rate and was among the top 10 countries with the highest numbers of preterm births in 2010. "We haven't been able to move that number very well, and although it's gone down somewhat in past years, it's no
|Contact: Craig Boerner |
Vanderbilt University Medical Center