An advisory panel for the U.S. Food and Drug Administration (FDA) voted to recommend revoking approval for a synthetic hormone called Makena. Makena is an obstetrics drug administered as a weekly injection to pregnant women at high risk of premature delivery.

An advisory panel to the Food and Drug Administration voted Wednesday to take a drug intended to prevent premature births off the market, saying that it remains doubtful that the drug works.

The recommendation, in a 14-1 vote, from the agency’s Obstetrics, Reproductive and Urologic Drugs Advisory Committee closed a three-day meeting on the clinical trial evidence supporting Makena, the only drug approved in the U.S. to prevent preterm births.