Itching in Pregnancy: When to Think of Obstetric Cholestasis

It is two in the morning and you are rubbing the soles of your feet against the sheet. Your palms are itching too, without a single spot. Itching in pregnancy is common, and usually nothing serious. But when it centres on the hands and feet and gets worse at night, you need to think of a liver condition specific to pregnancy: obstetric cholestasis, also called intrahepatic cholestasis of pregnancy (ICP).

It is rare, but worth knowing about, because it is easy to detect with a blood test and it changes how the end of pregnancy is monitored. Here is how to tell the difference, and what happens if you are diagnosed.

Itching in pregnancy: when is it harmless?

Most of the time. According to the UK's Royal College of Obstetricians and Gynaecologists (RCOG), about 25% of pregnant women have itching, and the vast majority do not have cholestasis. The NHS puts it down to hormonal changes and skin stretching.

Harmless itching often has these features:

• it mainly affects your growing bump, breasts and thighs, sometimes with dry skin;
• it varies with heat, sweating, synthetic clothes or a scented product;
• it calms down when the skin is well moisturised.

Eczema that is getting worse, or a rash with spots or patches, is a different skin problem and also deserves medical advice, the NHS points out.

What are the signs of obstetric cholestasis?

Intrahepatic cholestasis of pregnancy has a fairly typical pattern, described by the RCOG and by Tommy's, the UK pregnancy charity:

Less often, dark urine, pale stools or jaundice appear. In the UK, cholestasis affects about 7 pregnancies in 1,000, and up to 15 in 1,000 among women of Indian or Pakistani origin, according to the RCOG. It also comes back more often in women who have had it before. The causes are not fully understood: pregnancy hormones, genetic background and environmental factors are all mentioned.

How is it diagnosed?

With a blood test. The doctor first examines your skin to rule out eczema or another cause. They then prescribe liver function tests (the liver enzymes called transaminases) and a test for bile acids, components of bile that pass into the blood when bile does not flow properly.

Two useful points from the RCOG and Tommy's:

• bile acids can be raised while liver function tests are normal, which is why both are measured;
• early on, results can be normal: if the itching persists with no other explanation, the tests are repeated, often every one to two weeks.

If the symptoms are unusual or start very early, the doctor may ask for a liver ultrasound or a specialist opinion.

What are the risks for the baby?

For the mother, cholestasis is mainly very uncomfortable. For the baby, the risk depends mostly on the bile acid level, expressed in micromoles per litre. The RCOG summarises it like this, for a single pregnancy with no other complications:

Whatever the level, cholestasis increases the risk of premature birth, whether spontaneous or planned, and of meconium in the amniotic fluid: the baby's first stools, which can cause problems if breathed in. Admission to the neonatal unit is slightly more common. The RCOG states that no long-term risk to the child's health is known.

Other conditions add to the risk: gestational diabetes, pre-eclampsia or a twin pregnancy. Both of these conditions are also slightly more common with cholestasis, so they are monitored.

How is cholestasis monitored and treated?

Follow-up is handled by an obstetrician-gynaecologist, often with weekly blood tests at first. There is no treatment that directly lowers bile acids. A medicine called ursodeoxycholic acid is sometimes prescribed: according to the RCOG, it eases the itching a little for some women and may reduce the risk of premature birth, but it does not prevent stillbirth. As with any treatment in pregnancy, the dose is set by the doctor.

The most important thing is in your hands: keep track of your baby's movements. Any change, such as a baby moving less or differently, means an immediate check at the maternity unit. Our article on when you feel your baby move helps you get to know their pattern.

Will the birth be brought forward?

Sometimes, depending on the bile acid level and other risk factors. For a single pregnancy with no other complications, the RCOG says:

• 19 to 39: a planned birth around 40 weeks can be considered, or you can wait for labour to start naturally;
• 40 to 99: a planned birth at 38 to 39 weeks may be recommended;
• 100 and above: a planned birth at 35 to 36 weeks may be recommended.

Most often this means an induction, explained in our article on inducing labour. Cholestasis on its own does not mean you need a caesarean, and it does not limit your pain relief options, such as an epidural. The baby's heart rate is monitored continuously during labour when bile acids are very high.

And after the birth?

The itching disappears within a few hours or days. Blood tests take longer to return to normal: a check is usually offered around six weeks after the birth. If the results are still abnormal, a specialist opinion is sought.

Cholestasis tends to come back in later pregnancies. Note it in your pregnancy record and mention it at the very start of your next one. Allo Docteurs also points out that it remains a cause of premature birth: follow-up in a maternity unit used to high-risk pregnancies is a real plus. In the meantime, protect your nights: our article on sleeping well while pregnant may help.