How Progesterone Promotes Healthy Full-Term Pregnancy

A new study by Yale researchers shows for the first time that progesterone during pregnancy¹ directly prevents a common cause of pre-term delivery. The researchers found that progesterone helped the fetal membrane tolerate inflammation, enabling it to maintain integrity. Failure of the fetal membrane accounts for 1/3 of premature deliveries.

The fetal membrane is a layer of tissue matrix that surrounds the fetus and helps provide nutrition, respiration, removal of waste products and protection. During the last trimester in particular the fetal tissue undergoes rapid growth. Maintaining its integrity is of the utmost importance. Managing inflammation in general (such as stress) and ensuring enough dietary protein (to support matrix growth needs) are basics. However, the new research indicates that it is adequate progesterone that keeps the fetal membrane in tip-top working condition. Progesterone tends to be lowest in women who are stressed, tired, and lacking protein nutrition.

This means that women, especially women under stress or who have a history of preterm delivery, should use natural progesterone (never a highly toxic synthetic drug form) from the fourth or fifth month until delivery.