The positive role of progesterone supplementation in preventing miscarriage has been disputed in a recent study by English researchers.
Traditionally, supplementation of the hormone during early pregnancy was thought to increase the rates of live births and newborn survival, especially among women who had recurrent unexplained miscarriages. Progesterone is known as the hormone essential for the maintenance of pregnancy, preparing the wall of the uterus to accept a newly fertilised egg.
Now researchers have found that the hormone does not necessarily confer a survival benefit when given to women with previously unexplained recurrent miscarriages in their first trimester.
This is at odds with previous research, which had demonstrated a significantly lower risk of miscarriages among women who received progesterone than among those who received placebo or no treatment. There had been uncertainty surrounding progesterone use in early pregnancy, however, ever since it had first been used in the 1950s.
The study was part of a five-year trial, called PROMISE (Progesterone in Miscarriage Treatment). The large randomised controlled trial involved over 800 pregnant women, who were randomly assigned to either progesterone or placebo. Recurrent miscarriage was defined as “the loss of three or more pregnancies”.
It was seen that the rate of live births after 24 weeks of gestation was 65.8% (262 of 398 pregnancies) in the progesterone group, as compared with 63.3% (271 of 428 pregnancies) in the placebo group. In addition, there were no significant differences between the two groups in terms of clinical pregnancy, ongoing pregnancy, ectopic pregnancy, miscarriage, stillbirth, and neonatal outcomes, even when researchers adjusted for age, ethnicity, and women's medical and pregnancy history.
“Progesterone therapy in the first trimester of pregnancy did not result in a significantly higher rate of live births among women with a history of unexplained recurrent miscarriages,” concluded the study, which was published in the New England Journal of Medicine.
The study raises questions about the perception of progesterone as an effective treatment, commented study author Professor Arri Coomarasamy.
"We had hoped, like many people, that this research would confirm progesterone as an effective treatment. Though disappointing, it does address a question that has remained unanswered since progesterone was first proposed as a treatment back in 1953. Fortunately, there are a number of other positives that we can take from the trial as a whole,” he said.
Full article: http://www.nejm.org/doi/full/10.1056/NEJMoa1504927#t=articleDiscussion