Cholestasis of pregnancy is a liver condition that causes intense itching, typically in the third trimester, due to a buildup of bile acids in the bloodstream. It affects the flow of bile, a digestive fluid produced by the liver, and can pose risks to the baby if left unmanaged. The condition resolves after delivery, usually within days.
Why Bile Acids Build Up During Pregnancy
Your liver normally produces bile acids by processing cholesterol, then moves them into bile and out through your digestive system. Specialized proteins on liver cells handle this transport. In cholestasis of pregnancy, that transport system becomes overwhelmed.
For many women, the underlying issue is genetic. Up to 25% of those with cholestasis carry variants in a gene called ABCB4, which helps move protective fats (phospholipids) into bile. Phospholipids bind to bile acids and neutralize their toxicity. Outside of pregnancy, women with these gene variants still produce enough of the transport protein to keep things working. But the added metabolic load pregnancy places on the liver tips the balance, allowing bile acids to accumulate in the blood to levels that impair liver function and trigger symptoms.
What the Itching Feels Like
The hallmark symptom is intense itching without any visible rash. It usually starts on the palms of your hands and the soles of your feet, then can spread everywhere. The itching tends to be worst at night, sometimes severe enough to prevent sleep, and it often intensifies as your due date approaches. Scratching may eventually cause small bumps or linear marks on the skin, but these are secondary to the scratching itself, not a primary rash.
This pattern is what distinguishes cholestasis from other itchy conditions in pregnancy. A condition called PUPPP, for instance, produces visible raised plaques that typically start on the abdomen within stretch marks and spread outward. With cholestasis, the itching comes first, the skin looks normal, and the palms and soles are the epicenter.
Who Is at Higher Risk
Several factors increase the likelihood of developing cholestasis during pregnancy:
- Family history: A genetic component is well established, and having a close relative who had the condition raises your risk substantially.
- Twin or multiple pregnancies: The greater hormonal and metabolic demands of carrying multiples put more stress on bile transport.
- Hepatitis or other liver infections: Pre-existing viral hepatitis is independently associated with cholestasis.
- Gestational diabetes or high blood pressure in pregnancy: Both conditions show a statistically significant link.
- Higher BMI at delivery and hyperlipidemia: Elevated cholesterol and body weight also contribute.
- IVF pregnancies: Conception through in vitro fertilization carries a higher incidence.
How It Is Diagnosed
Diagnosis relies on a blood test measuring total bile acid levels. Itching alone isn’t enough to confirm the condition, since many things cause itching in pregnancy. The bile acid result determines both the diagnosis and the severity category, which directly influences how your pregnancy is managed.
The Royal College of Obstetricians and Gynaecologists defines three tiers: mild (bile acids 19 to 39 micromol/L), moderate (40 to 99 micromol/L), and severe (100 micromol/L or higher). Liver function tests are usually checked alongside bile acids. Because bile acid levels can fluctuate, testing may be repeated if initial results are normal but symptoms persist.
Risks to the Baby
The primary concern with cholestasis is its effect on the baby, not the mother. The condition is associated with preterm birth (both spontaneous and medically planned), meconium-stained amniotic fluid, fetal distress, and in the most serious cases, stillbirth.
These risks are dose-dependent, meaning they rise in proportion to how high bile acid levels climb. The greatest danger of stillbirth applies to severe cases where bile acids exceed 100 micromol/L. For women with mild elevations, the absolute risk is much lower. Research suggests stillbirth in cholestasis occurs through sudden fetal cardiac arrest rather than gradual placental failure, which is part of what makes it unpredictable. Standard fetal monitoring tools are designed to evaluate placental function and may not reliably detect this type of event, which is why delivery timing becomes a key part of management.
Treatment and Symptom Relief
The most commonly used medication for cholestasis is ursodeoxycholic acid, a naturally occurring bile acid that works by improving bile flow in the liver. It shifts the composition of the bile acid pool so that 60 to 70% of circulating bile acids become this less toxic form, replacing the more harmful types. It also appears to help the placenta export bile acids away from the fetus.
Studies show it modestly reduces itching, though not always to a degree that feels dramatic. Its main value lies in altering the bile acid profile to reduce toxicity. Treatment is typically guided by how high bile acid levels are and when in pregnancy the diagnosis is made.
For itching relief in the meantime, cool baths, lightweight clothing, and keeping the bedroom cool at night can help take the edge off, though nothing eliminates the itch entirely until delivery.
When Delivery Is Planned
Because the risk of stillbirth in cholestasis increases after 37 weeks, early delivery is a central part of management. The exact timing depends on the severity of bile acid elevation. Women with severe cholestasis (bile acids at or above 100 micromol/L) are generally delivered earlier than those with mild cases. Your care team will weigh the risks of prematurity against the risks of continuing the pregnancy, using your bile acid levels as the primary guide.
For mild cases, delivery closer to 37 to 38 weeks is common. For moderate or severe cases, earlier delivery may be recommended. This is an individualized decision, and your provider will factor in your specific lab trends, symptoms, and pregnancy history.
After Delivery
The itching typically disappears within a few days of giving birth, and bile acid levels return to normal as the pregnancy-related stress on the liver resolves. Follow-up blood tests are recommended around two to three months postpartum to confirm that liver function has fully normalized. Persistent abnormalities at that point would prompt further investigation for an underlying liver condition unrelated to pregnancy.
That postpartum visit is also the time to discuss two important topics: contraceptive choices (some hormonal options can affect bile flow) and the likelihood of recurrence. Cholestasis of pregnancy comes back in roughly 40 to 90% of subsequent pregnancies depending on whether the cause is genetic. A recent study of 104 women found a 44% recurrence rate overall, while a Finnish study found recurrence as high as 92% in cases with a strong family history compared to 40% in cases without one. If you’ve had cholestasis once, your provider will likely plan for early bile acid monitoring in your next pregnancy.