Also called "Chorioamniotic Seperation", or Placental abruption it is most common in late birth, after 20 weeks. Anything sooner will most likely result in excessive hemmoraging and cause the baby to abort. Late in pregnancy it will require lots of bedrest. Other cases can include only a slight tear and mean severe pain for the mother but no apparent bleeding, still, this should be reported so your doctor can monitor and it does not turn into something more threatening to you and the baby.
Threatening to the baby because the placenta is a vital 'organ' to the baby while in gestation and separation can create distress (rapid, abnormal heartbeat, low blood pressure) in your baby which in late pregnancy could require a premature delivery.
The best remedy for placenta separation is to closely monitor it with your doctor, and only take the advice of your doctor.
It means get to the hospital NOW. The placenta separating can mean that you could have a miscarriage if you don't get help to stop it.
An abruptio placentae is a premature separation of the placenta from the uterine wall.
Placenta abruptio or placental abruption is abnormal separation of the placenta from the uterine wall.
Separation of the placenta from the uterine wall beginning at the outermost edge of the placenta. Blood from the implantation site exits immediately through the vagina followed by the placenta, which descends sideways into the vagina.
An abruptio placentae is a premature separation of the placenta from the uterine wall.
concealed hemorrhage
Yes, using cocaine in particular can cause the placenta to separate from the uterus during pregnancy (placental abruption).
it increases the risk for post partum hemorrhage and infection The person who delivers the placenta should ensure it is complete so this doesn't happen. an operation may be required to remove the remaining placenta.
Afterbirth
I believe the placenta is directly attached to the uterine wall.
Check out this site, or you could search "placental abruption" or abrutio placentae" in any search engine. http://en.wikipedia.org/wiki/Placental_abruption
The placenta is some times called the 'after birth' as it is expelled from the uterus after the baby is born.
the causes of polyhydromnious is meternal cause and fetal cause and itis effects it may cause premature separation of placenta.