Placenta previa
Placental abruption
Vasa previa and velamentous insertion
A small amount of vaginal bleeding during labour is normal (an amount less than a normal period). This can be pink, bright red or dark brown in colour sometimes mixed with mucus as a show, sometimes mixed with amniotic fluid as the waters break. Slight bleeding can be something noticed on a sanitary pad, or staining underwear or when wiping with toilet paper. However, a few women don't experience any vaginal bleeding at all during their labour, only at the birth. A small amount of blood can come away during prelabour, and/or the 1st and 2nd stages of labour (continuously or intermittently), as the cervix dilates and the baby negotiates the birth canal. It can also start (or become slightly heavier) after an internal vaginal examination. Significant bleeding (soaking a pad or more) during labour is of concern, and is referred to as an Intrapartum Haemorrhage (IPH). Very heavy bleeding after the baby is born is referred to as a postpartum haemorrhage (PPH).
The main causes of an intrapartum haemorrhage are placenta previa (low lying placenta), placental abruption (the placenta separating too early from the wall of the uterus) or unusual placenta formations such as vasa previa and velamentous insertion.
Updated August 2006
Gabbe SG, Niebyl, JR, Simpson JL. Obstetrics, Normal and problem pregnancies, 4th Edition, 2001, Churchill Livingstone, New York.
Stables D. and Rankin J. Physiology in Childbearing with Anatomy and Related Biosciences. 2004, Bailliere Tindall, Edinburgh.