Progesterone Gel Reduces Rate of Premature Birth by 45 Percent

April 7, 2011— -- The medical community was sent into an uproar recently when KV Pharmaceuticals jacked up the price of 17P, one of the only drugs currently approved to treat preterm birth. But hope for a new, affordable alternative treatment for certain women at risk of preterm delivery may be on the horizon thanks to new research from the National Institutes of Health.

Unlike 17P, which delivers synthetic progesterone by injection, the drug in question is a naturally-derived progesterone gel applied vaginally. According to results published Wednesday by the NIH, the gel reduced the rate of preterm birth by 45 percent in women identified as having a short cervix, one of many risk factors for premature delivery.

One of the hardest parts of predicting and treating preterm birth is that early delivery can occur for a number of reasons, and each may require different treatment approaches, says lead author on the study, Dr. Roberto Romero, program head for Perinatology Research and Obstetrics and chief of the Perinatology Research Branch.

One risk factor is having had a preemie baby already -- the risk factor that makes a woman eligible for 17P. The problem is, about 60 percent of preterm babies come from a mother who does not have a history of preterm birth, so "the question becomes, how else can we assess risk?" says Romero.

This is where testing for a short cervix comes in. Using a simple ultrasound, doctors can screen for a short cervix during pregnancy and identify a woman as at risk for preterm birth. By daily applying the gel, which currently costs between $10 and $15 and is prescribed during in vitro fertilzation, the rate of these preterm births before the 33rd week of pregnancy can be nearly cut in half. Though this will only address a small portion of all the preterm births, Romero says that this study argues for universal screening of cervix length to prevent what he estimates will be thousands of premature births annually in the U.S.

Bit by Bit – Treating Premature Birth

In 2006, 12.8 percent of all infants born were preemie. Premature birth carries with it an increased risk of death in the first year of life, breathing difficulties, cerebral palsy, learning disabilities, blindness and deafness.

About of a third of the time, preterm delivery must be induced by a doctor because of complications in the baby's development. For the other two-thirds, however, premature delivery is spontaneous and often difficult to predict. Using known risk factors, such as prior history and cervix length, obstetricians can try to be proactive about delaying or preventing premature birth. Nearly half a million babies are born premature each year.

"We have to tackle the problem of preterm births from a number of different approaches. I see this gel as an added approach, not a substitute for 17P," says Dr. M. Kathryn Menard, director of the Center for Maternal and Infant Health at the University of North Carolina School of Medicine. Menard also points out that when the gel was tested among women with a prior history of preterm birth, it was not found to be effective. This highlights the fact that the drugs will most likely be effective for different populations of pregnant women.

The next step for this progesterone gel will be to gain FDA approval for use in women at risk for premature birth, whereas currently it is only approved as supplemental treatment for women trying to conceive with in vitro fertilization, says Dr. Ashlesha Dayal, an expert in Maternal Fetal Medicine, director of Labor and Delivery at Montefiore Medical Center and co-author on Wednesday's study.

Because the drug is already in use, it has a known safety margin when used daily in women, says Romero. Among women in the study, adverse events were similar between women taking the gel and those using a placebo gel.