Cephalopelvic disproportion, or CPD, is a complication of pregnancy and childbirth in which a baby’s head and body are too large to safely fit through the pelvis of its mother.http://www.americanpregnancy.org/labornbirth/cephalopelvicdisproportion.html While true cases of CPD are likely rare, this condition is often diagnosed after a labor has failed to progress.http://www.americanpregnancy.org/labornbirth/cephalopelvicdisproportion.html

There are two forms of CPD which can affect a mother and baby during pregnancy and birth: absolute CPD and relative CPD.http://www.ican-online.org/vbac/cephalopelvic-disproportion-cpd In absolute CPD, the more rare of the two forms, the disproportion is due to a pelvic abnormality that may have been caused by a previous injury or a growth disorder in childhood, such as rickets.http://www.ican-online.org/vbac/cephalopelvic-disproportion-cpd Relative CPD, also sometimes known as Feto-Pelvic Disproportion, involves CPD in the absence of the above factors.http://www.ican-online.org/vbac/cephalopelvic-disproportion-cpd

Having a larger than average baby can raise a woman’s risk of experiencing cephalopelvic disproportion.http://www.americanpregnancy.org/labornbirth/cephalopelvicdisproportion.html Large babies can develop due to such factors as maternal diabetes or gestational diabetes, postmaturity, or a pregnancy progressing past its due date, genetics, or even a mother having experienced previous pregnancies.http://www.americanpregnancy.org/labornbirth/cephalopelvicdisproportion.html A baby who is in an abnormal position, or “malpresentation,” and abnormalities of a mother’s pelvis, as described above, can also contribute to the risk of CPD.http://www.gynaeonline.com/comp-lab.htm

Since the methods of diagnosis for cepahopelvic disproportion, including clinical pelvimetry (measuring the pelvis prior to birth) and ultrasound weight estimates, are not entirely accurate and the ligaments of a pregnant mother’s pelvis relax prior to birth to allow more room for a baby to maneuver, many medical providers will offer a “trial of labor” even if relative CPD is suspected.http://www.gynaeonline.com/comp-lab.htm In the case of absolute CPD, a caesarean section is the most common management option, however, some women are still able to deliver vaginally in these cases.http://www.ican-online.org/vbac/cephalopelvic-disproportion-cpd

Some professionals in the realm of pregnancy and birth believe that CPD is often misdiagnosed and, because of its rare nature, is overdiagnosed in pregnant women. http://www.americanpregnancy.org/labornbirth/cephalopelvicdisproportion.html Indeed, according to some studies, as many as 65% of women who have been diagnosed with CPD in pregnancy can go on to have successful vaginal deliveries.http://www.americanpregnancy.org/labornbirth/cephalopelvicdisproportion.html

The content in this page is not a substitute for professional medical advice. Please contact a doctor before using the information presented here.