Placental abruption

Placental abruption (Also known as abruptio placenta) in biology, is the separation of the placental lining from the uterus of a female. In humans, it refers to the abnormal separation after 20 weeks of gestation and prior to birth. It occurs in 1% of pregnancies world wide with a fetal mortality rate of 20-40% depending on the degree of separation. Abruption placenta is also a significant contributor to maternal mortality.

Pathophysiology
Trauma, hypertension, or coagulopathy, can lead to bleeding into the decidua basalis. This can push the placenta away from the uterus and cause further bleeding. Bleeding through the vagina occurs 80% of the time, though sometimes the blood will pool behind the placenta.

Women may present with vaginal bleeding, abdominal or back pain, abnormal or premature contractions, fetal distress or death.

Abruptions are classified according to severity in the following manner:


 * Grade 0: Assymptomatic and only diagnosed through post partum examination of the placenta.
 * Grade 1: The mother may have vaginal bleeding with mild uterine tenderness or tetany, but there is no distress of mother or fetus.
 * Grade 2: The mother is symptomatic but not in shock. There is some evidence of fetal distress can be found with fetal heart rate monitoring.
 * Grade 3: Severe bleeding (which may be occult) leads to maternal shock and fetal death. There may be maternal disseminated intravascular coagulation.

Risk factors

 * Maternal hypertension is a factor in 44% of all abruptions.
 * Maternal trauma, such as motor vehicle accidents, assaults, falls, or nosocomial
 * Drug use is a factor, particularly tobacco, alcohol, and cocaine.
 * Short umbilical cord
 * Prolonged rupture of membranes (>24 hours)
 * Retroplacental fibromyoma
 * Maternal age: pregnant women who are younger than 20 or older than 35 are at greater risk.
 * Previous abruption: Women who have had an abruption in previous pregnancies are at greater risk.
 * Multipara: Women who have given birth many times are at greater risk. (source?)

The risk of placental abruption can be reduced by maintaining a good diet including taking folic acid, regular sleep patterns and not smoking or drinking alcohol.

Intervention
Placental abruption is suspected when a pregnant woman has sudden localized uterine pain with or without bleeding. The fundus may be monitored because a rising fundus can indicate bleeding. An ultrasound may be used to rule out placenta previa but is not diagnostic for abruption. The mother may be given Rhogam if she is Rh negative.

Treatment depends on the amount of blood loss and the status of the fetus. If the fetus is less than 36 weeks and neither mother or fetus are in any distress, then they may simply be monitored in hospital until a change in condition or fetal maturity whichever comes first.

Immediate delivery of the fetus may be indicated if the fetus is mature or if the fetus or mother are in distress. Blood volume replacement and to maintain blood pressure and blood plasma replacement to maintain fibrinogen levels may be needed. Vaginal birth is usually preferred over Caesarian unless there is fetal distress. Caesarian section is contraindicated in cases of disseminated intravascular coagulation.