Maternity wards have long forbidden women in labor to eat or drink. Even when labor goes on and on, the bill of fare is usually limited to ice chips.

Now a systematic review of existing studies has found no evidence that the restrictions have any benefit for most healthy women and their babies.

The prohibitions are meant to reduce the risk of Mendelson’s syndrome (named for Dr. Curtis L. Mendelson, the New York obstetrician who first described it in the 1940s), which can occur if the contents of the stomach are drawn into the lungs while the patient is under general anesthesia.

While rare, the syndrome can be fatal. But nowadays the use of general anesthesia during labor and delivery is also rare. Caesarean sections are generally done using regional anesthesia.