21.1  What causes late pregnancy bleeding?

The most common causes of late pregnancy bleeding, or ante-partum haemorrhage (APH), are due to bleeding from the placenta, but there are other less common causes arising in the uterus or other parts of the reproductive tract. First, we will list the causes briefly, and then describe placental abruption, placenta previa and ruptured uterus in detail, because these are conditions that require your immediate life-saving intervention.

  • Placental abruption: this condition occurs if the placenta pulls away prematurely (too soon) from its normal attachment site in the top two-thirds of the uterus.
  • Placenta previa: this condition is when the placenta has attached too low down in the uterus, very close to, or even covering, the cervix.
  • Ruptured uterus: this can occur during a prolonged or obstructed labour when the uterus, after a long effort to expel the fetus, gives way and tears or bursts.
  • Ruptured varicose vein in the genital area: this can occur if a vein becomes twisted and dilated. As a result, it can easily be traumatised and bleed, usually during labour and delivery.
  • Heavy show: the mucus mixed with bloody fluid that comes from the birth canal at the start of labour is called the show; sometimes, when this mucus plug detaches it may be followed by brisk and heavy bleeding called a heavy show, which often stops on its own without any intervention. But she should always be referred.

Learning Outcomes for Study Session 21

21.2  Placental abruption