Background: In maternal fetal medicine, gender differences in outcome are often observed.
Objective: This article reviews the fetal sex-dependent differences found in many aspects of pregnancy, from conception through birth.
Methods: The MEDLINE, EMBASE, and Current Contents databases were searched, for the years 1985 to 2006, using the following Medical Subject Headings and text words: fetal gender, finale, female, sex ratio at birth, pregnancy outcome, preterm birth, and stillbirth.