According to a new study, giving progesterone to women who have had three or more miscarriages does not improve their chances of completing their pregnancy term, NY Times reports.
The study was published on Wednesday in The New England Journal of Medicine.
Previous studies have suggested that progesterone could lower the risk among women with a history of recurrent miscarriages.
The results of the study showed that 65.8 percent of the women given progesterone gave birth to a baby, compared with 63.3 percent of the control group, which was not a significant difference.
"After more than 60 years of debate, we now know that progesterone treatment in early pregnancy isn't the answer for women with unexplained recurrent losses," said lead researcher Dr. Arri Coomarasamy, a professor of gynecology at the Institute of Metabolism and System Research at University of Birmingham in England, according to Health.
The study was conducted on more than 800 women at 36 sites in Britain and nine in the Netherlands.
"It's an awfully good study, and the first well-designed study on this topic," said Dr. Samantha M. Pfeifer, the chairwoman of the practice committee for the American Society for Reproductive Medicine, who was not involved in the new research.
"There's always disappointment whenever you find out that a magic bullet isn't a magic bullet," she added.
Progesterone is often a first-line treatment for unexplained recurrent miscarriages.
The study also suggested that supplemental progesterone did not lead to an increase in congenital abnormalities.
"Progesterone doesn't cause harm," said Dr. Arri Coomarasamy, the trial's lead author and a professor of gynecology at the University of Birmingham.
Also, some experts wondered if progesterone should have been given to the study subjects before they were pregnant.
"My big concern is they are starting the progesterone too late," said Dr. Mary D. Stephenson, chief of obstetrics and gynecology at the University of Illinois at Chicago, who was not involved in the new research.
"You have to start it before they are pregnant."
According to science daily, even though the results of the PROMISE (progesterone in miscarriage treatment) trial will be disappointing to many, it will allow researchers to explore other treatments that can reduce the risk.
Professor Arri Coomarasamy explained, "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."
