Home > Encyclopedia of Children's Health > Breech Birth

Definition

Breech birth is the delivery of a fetus (unborn baby) in a bottom- or foot-first position. Between 3 to 4 percent of fetuses start labor in the breech position, which is a potentially dangerous situation.

Description

Throughout most of pregnancy the developing fetus is completely free to move around within the uterus. Between 32 and 36 weeks, however, the fetus becomes so large that movement is restricted. It is much harder for the fetus to turn over, so whatever position it has assumed by this point is likely to be the same position that he or she will be in when labor begins.

For reasons that are not fully understood, almost all unborn babies settle into a head down, or vertex, position. The fetus is upside down in the uterus, and the head will dilate the cervix (or...