Gastroesophageal reflux disease in pregnancy.

Heartburn during pregnancy occurs in approximately two thirds of all pregnancies. The origin is multifactorial, but the predominant factor is a decrease in LES pressure resulting from female sex hormones, especially progesterone. Mechanical factors play a small role. Serious reflux complications during pregnancy are rare outside the obstetric setting. Therapy involves lifestyle modifications and nonsystemic medications as the initial choices. H2 blockers are probably safe in severe and refractory cases.