What causes itching in pregnancy? Itching is the most common skin complaint in pregnancy. It affects one in six pregnant women. The causes are many and varied and each case calls for careful evaluation by the doctor. The cause could be from a pre-existing skin condition; it could also be a manifestation of a condition affecting the liver, thyroid gland or other body systems, developing for the first time in pregnancy. Itching could also be a result of skin conditions that develop in - and are specific to pregnancy. In this latter category, there is almost always a rash. It is discussed in more detail below. Experts acknowledge that there are many cases of generalized itching in pregnancy which do not fit in any of these categories and whose causes therefore remain unknown. Obstetric cholestasis What are the liver conditions causing itching in pregnancy? There are several liver conditions that cause symptoms of generalized itching, be it in pregnancy or a non-pregnant state. A doctor has to be on the lookout for and always try to exclude the pregnancy-specific cholestasis. It is generally called "obstetric cholestasis". In the USA, it is also called "pruritus gravidarum". Its importance lies in the fact that, if unrecognised, it could lead to loss of the baby through stillbirth. It also makes the woman prone to premature labour. Some specific blood tests are required to establish the diagnosis, after which close monitoring of the disease and well-being of both the mother and the baby has to be maintained. If seen to be progressive, delivery may have to be brought forward. Typically, apart from itching, the mother remains well. Obstetric cholestasis clears up soon after delivery. How common is obstetric cholestasis? Uncommon. The estimated incidence in the UK is five to seven in every 1000 pregnant women. Severity varies widely. It is relatively more common among Swedes and some native American tribes. In Chile for instance, one in every 40 pregnancies is affected and for women of some native tribes, the incidence is double that. This means there is almost certainly some genetic susceptibility. How is Obstetric cholestasis diagnosed? The condition is suspected from the symptoms. This will prompt blood tests based mainly on liver function. Some liver enzymes (transaminases) and specifically bile acids tend to be raised in this condition. The levels will be monitored approximately every week to monitor the progression of the condition. Are those enzymes always raised in this condition? No, and that can make the management and decision making rather tricky. However, if the symptoms are typical and other itchy skin conditions have been conclusively excluded, it will be treated as obstetric cholestasis and managed accordingly. Are there any risks associated with this obstetric cholestasis? Obstetric cholestasis is known to be associated with an increase in the risk of stillbirth the timing of which is very hard to predict. Up to 2% of affected pregnancies will end in stillbirth. There is also an increase in premature delivery which could be spontaneous or through induction of labour or emergency caesarean section when there is significant concern about fetal wellbeing. Up to 60% of affected women will deliver prematurely. Can obstetric cholestasis be treated? Strictly speaking, no. Emmolients such as calamine lotion, E45®, Diprobase® etc. are offered to try to relieve symptoms. Effectiveness is modest at best. Newer products which have come on stream more recently such as Balneum Plus® appear to hold more promise Ursodeoxycholic acid (UDCA) has been suggested as a possible treatment for relieving symptoms and possibly protecting the baby. The evidence to its effectiveness in this regard remains weak. Brand names of UDCA include Destolit®, Urdox®, Ursogal® etc.