Obstetric Cholestasis

Obstetric cholestasis (OC) or Intrahepatic cholestasis of pregnancy, affects around 0.7% of pregnancies in a multi-cultural society.  If you have been diagnosed with this condition, it may have started with itchy skin, which may have been worse on your hands and feet, but can be anywhere on your body.

It is caused when the bile that flows through your liver slows down or even stops.  This leads to bile acids building up in your liver, which then leak out into your bloodstream and cause itching.  Some women find that the itching is worse at night, affects their sleep and can lead to problems with emotional wellbeing.  Sometimes the itching can be so severe that the skin becomes damaged. Other symptoms can include dark urine, pale stools, fatigue, liver pain (pain in right upper abdomen) and feeling generally unwell.

OC isn’t routinely tested for.  If you have some of these symptoms then your midwife will ask to take your blood to see what your bile acid levels are and check your liver function.  It isn’t known exactly why women develop OC, but it is thought to be a combination between genetic, hormonal and environmental reasons.  Women with pre-eclampsia or with multiple pregnancies are more likely to develop OC.

If you have been diagnosed with OC you will likely be offered an induction of labour (IOL). The timing of the IOL depends on the level of bile acid in the blood.  In cases of severe OC (bile acid more than 40), women are likely to be offered an IOL between 37/40 and 39/40. There is some evidence to say that the chance of stillbirth is increased for women who have severe OC.  In milder cases, women will be offered an IOL between 39 and 40 weeks of pregnancy.  At 36/40 - risk of stillbirth is 0.06% compared to 0.02% in an unaffected pregnancy At 40/40 - risk of stillbirth is 0.2% compared to 0.06% in an unaffected pregnancy.

The chance of premature birth is higher with OC.  There is a hypothesis that the bile acids can cause tightenings.  Babies born to mothers with OC are also more likely to have meconium in their waters. This is likely to be because of the extra movement of fluid through the bowel, which causes baby to open their bowels earlier than normal.  Increased bile acids can also disrupt the production of surfactant in baby’s lungs, which helps them to fill their lungs with air at birth and maintain breathing.  Because of this more babies are admitted to special care when their mother has OC -a rise of 6.4% compared to babies born to mothers without OC.