About Obstetric Cholestasis (OC)
1.What is Obstetric Cholestasis?
Obstetric cholestasis (OC) is a liver disorder which occurs during pregnancy. It is also referred to as intrahepatic cholestasis of pregnancy (ICP) It affects about 1 in 200 pregnant women each year in the UK, but may be slightly more common in women of Asian origin. The main symptom is itching on the hands and feet. The causes of OC are not yet understood.
Itching (also called pruritus):
This can be mild or so severe that you scratch your skin until it bleeds. It can be constant or intermittent.
The itch usually affects the hands and feet, but may occur anywhere on your body.
Many women find that it is worse at night and it disturbs their sleep.
There is no rash associated with the itch, but there may be marks on your skin from scratching (also called excoriation).
Although the symptoms of OC are distressing for you, they should resolve rapidly after your baby is born and have no long term effects on your health.
Other symptoms:
Some (but not all) women with OC develop other symptoms associated with cholestasis. These may include jaundice (yellowing of the skin and whites of the eyes), dark urine and pale stools.
It is not uncommon for women with OC to feel generally unwell, tired and to lose their appetite.
To make the diagnosis of OC, other liver conditions need to be ruled out first with either blood tests or liver ultra sound scanning. These other conditions may include viral hepatitis, autoimmune hepatitis and gallstones.
Your doctor will need to ask you about your symptoms and may ask whether anyone else in your family has had liver problems during pregnancy.
Blood tests:
Liver function tests (LFT’s) – this blood test looks at how well the liver is working by measuring the level of different enzymes. One or more of the following enzymes may be measured in a liver function test – AST, ALT, Alkaline phosphatase or GGT. The AST and ALT are the ones that are used to make the diagnosis of OC.
Bile acid test – bile acids are chemicals produced in the liver to help with digestion. In OC the flow of bile acids in the liver is reduced and they build up in the blood. A bile acid test is believed to be the most specific test for OC. Bile acids are thought to be harmful because they may be responsible for some of the complications that could affect your baby if you have OC.
Unfortunately there is no cure for OC, and most treatments are aimed at relieving the itch. Some may also help to protect your baby.
Ursodeoxycholic Acid (UDCA also called Urso)
-This is a bile acid, which may seem a bit odd as bile acid levels are raised in OC. However, UDCA is believed to be a more ‘friendly’ bile acid that displaces the more harmful bile acids from the blood.
-Many doctors believe that UDCA helps to protect your baby from the harmful effects of bile acids as well as helping to relieve your symptoms.
-A recent study showed that women with OC who have high bile acids (greater than 40 micromol/L) commonly respond to UDCA. This prospective study did not show that women with bile acid levels under 40 responded. However, several previous case reports and small series did show that women with lower bile acid levels responded to UDCA. A larger study may be required to clarify whether women with less markedly raised bile acids respond to the drug.
Piriton (Chlorpheniramine)
-This is an antihistamine. This type of drug is used to treat itching in other conditions (eg allergies).
-There is no evidence to prove that it helps in OC, and indeed many women would agree with this.
-Another effect of piriton is that it causes people to feel drowsy, and this may help if your itch is disturbing your sleep.
Aqueous Cream & Menthol
-This is a cream that may help soothe your skin, but will not improve your OC and may not relieve the itching.
Dexamethasone
-This is a steroid that has been used in the past to help relieve itching and to improve liver function and bile acid levels.
-Betamethasone is another steroid drug. You may be given this to help mature your baby’s lungs if your doctor is planning that your baby will be delivered very early or if you go into preterm labour.
Oral Vitamin K
-You may be at increased risk of bleeding heavily following the delivery of your baby. Oral vitamin K is given to help prevent the chance of this happening.
5. Does my baby need treatment?
-You may be offered a drug, Ursodeoxycholic Acid (also referred to as Urso or UDCA) that can help improve the liver function and ease the itching. Some researchers also believe it will help to protect your baby. Anecdotal evidence so far shows that it appears to be safe and, for many women, effective. However, it is also important that you realise this drug is still unlicensed for use in pregnancy (it hasn’t had a large clinical trial to show if it’s safe). It is therefore prescribed with what’s called ‘informed consent’, that is, you take it knowing that it hasn’t been rigorously tested.
-It may be that you will be asked to come into hospital more frequently to have your baby’s heart rate monitored (cardiotocograph). There is no evidence to suggest that carrying out this procedure will identify the ‘at risk’ baby but it may help to reassure you. On the other hand, some women report that having to go into hospital so frequently actually increases their anxiety.
-You may be asked to have additional ultra-sound scans of your baby. This is usually to check on your baby’s well-being and growth. There is no evidence to suggest that OC can affect the growth of your baby.
-You may be asked to keep a kick-chart to help monitor your baby’s movements. There is much debate to the value of kick-charts but some women do find it helpful to use them.
-Talk to your consultant or midwife about what you feel will help you and your baby.
6. Is there anything else I can do?
Other things that women have found useful in the past include:
Lower fat diets
Rest
Cool clothing
Relaxation or meditation
Counselling
-Some women have tried complementary medicines such as milk thistle and dandelion. However, it is important, as with all complementary medicines, that you discuss this with your doctor.
-Women are generally advised to avoid alcohol in pregnancy, and although it has no direct effect on OC, this is a sensible approach.
The causes of OC are not yet fully understood, but it is likely to be due to a number of different factors, including:
Hormones
-It is thought that the pregnancy hormones (estrogen and progesterone) have an effect on the ability of the liver to transport some chemicals, including bile acids.
-It seems that in some women the liver is not able to cope with the rise in the levels of estrogen and progesterone that occurs as pregnancy advances, and the flow of things like bile acids is greatly reduced.
-This leads to them building up in the blood and results in the symptoms of OC.
Genes
-OC is more common in certain populations, including Scandinavians and South Americans, and it may also run in families.
-These observations raise the possibility of a genetic cause for the disease.
-Lots of research has been done to try to establish exactly what the link is, and some genetic variation in women with the disease has been found.
-However, it should be emphasised that researchers are a long way from explaining all cases of OC by means of genetic analysis.
Environment
-More women are diagnosed with OC during the winter months.
-Although the reason for this is not clear, it suggests that there is an environmental trigger for the condition, such as a reduced exposure to sunlight or a change in diet.
While OC is a distressing condition, the symptoms will resolve soon after your baby is born. So far, there is no evidence so far to show that it has any long term effect on your health or that of your baby.
There is a small chance that you will bleed heavily following the delivery of your baby, but treatment with oral vitamin K may prevent this.
Several studies have shown that gallstones occur more commonly in women with OC.
OC has been reported to be associated with an increased risk of spontaneous premature birth, fetal distress and stillbirth.
Most hospitals chose to monitor women with OC more closely and to deliver the babies early (between 37 and 38 weeks) in order to minimize any risk to your baby.
With active management (which usually means treatment and choosing to deliver early) the risk of stillbirth in an OC pregnancy is believed to be the same as that for a normal pregnancy (1%).
You will need to have follow up checks on your liver. This is because sometimes there may be an underlying liver condition which is not OC that has caused the itching and abnormal liver readings during your pregnancy. Ideally the check up should include a liver function and bile acid test. You don’t need to rush to have this done – 6-12 weeks is fine.
If the results still show elevated ALT/AST or bile acid levels you will need to have the tests repeated. If, after six months your levels are still not improving it may be advisable to be referred to a Hepatologist (liver specialist) or, if there not one in your area, a Gastroenterologist with a special interest in the liver. You may have another liver condition (although this is quite rare) or your liver is just taking a little while to settle down. This has been known to happen with women who have had OC. Whatever the underlying reason you will need to see a specialist who will advise you on what to do next.
11. Is there anything else I should know?
(Text will be add at a later stage)
Reported recurrence rates vary with some researchers stating 60% and others up to 90%. What is known is that women who have OC in one pregnancy are very likely to develop it again in a subsequent one.
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