Intrahepatic Cholestasis of Pregnancy (ICP) is a liver condition that can develop during pregnancy, primarily in the later stages. It is characterized by intense, generalized itching, often without a rash, and can pose risks to the developing baby. This condition temporarily affects the liver’s ability to process bile, leading to a buildup of bile acids in the mother’s bloodstream.
What is Cholestasis of Pregnancy?
Intrahepatic Cholestasis of Pregnancy (ICP) is a liver disorder specific to gestation, where the normal flow of bile from the liver is disrupted. Bile, a digestive fluid, then accumulates in the liver and spills into the bloodstream, causing severe itching. This itching typically starts in the late second or early third trimester, often worsening at night and frequently affecting the palms of the hands and soles of the feet.
Diagnosis of ICP involves blood tests that measure serum bile acid levels and liver enzymes. A total bile acid level of 10 micromoles per liter or higher, in conjunction with itching, confirms the diagnosis. While the exact cause is not fully understood, ICP is considered a multifactorial condition.
Why Delivery Timing is Critical
Delivery timing is a significant consideration in pregnancies affected by ICP due to risks to the baby. Elevated bile acid levels in the mother can cross the placenta and accumulate in the fetus and amniotic fluid, leading to complications. These complications include an increased risk of premature birth, fetal distress, meconium staining of the amniotic fluid, and, most concerningly, stillbirth.
The risk of these adverse outcomes, particularly stillbirth, increases as the pregnancy progresses and with higher maternal bile acid levels. Although the exact mechanism for stillbirth is not fully understood, it is thought to be related to the toxic effects of bile acids on the fetal heart.
Navigating Delivery Guidelines
While the idea of delivery by 34 weeks might arise, current guidelines for ICP-affected pregnancies are individualized and recommend delivery later in gestation. The main factor guiding delivery timing is the level of total bile acids in the mother’s blood, balancing the risks of continued ICP exposure against the risks associated with prematurity. For bile acid levels below 40 µmol/L, the risk of stillbirth is similar to that of a normal pregnancy, allowing for delivery closer to term, between 36 to 39 weeks.
For moderate elevations, such as bile acid levels between 40 and 99 µmol/L, delivery is recommended in the earlier part of the 36-to-39-week window, around 38-39 weeks. In cases of very high bile acid levels, defined as 100 µmol/L or more, the risk of stillbirth significantly increases to over 3%. For these severe cases, earlier delivery, around 36 weeks, is advised.
Fetal monitoring, including non-stress tests and biophysical profiles, is employed to assess the baby’s health. However, these tests provide reassurance but do not eliminate the risk of stillbirth, which can occur suddenly even after normal monitoring results. The decision for delivery timing is a collaborative one between the pregnant individual and their healthcare provider, considering individual circumstances, bile acid levels, and overall fetal well-being.
Treatment and Post-Delivery Considerations
Management of ICP before delivery involves medication and comfort measures to alleviate maternal symptoms and reduce bile acid levels. The frontline medication is Ursodeoxycholic Acid (UDCA), also known as Ursodiol. UDCA works by improving liver function and helping to reduce the concentration of bile acids in the bloodstream, which can help alleviate intense itching. While UDCA effectively reduces maternal symptoms and improves liver function tests, its impact on preventing adverse fetal outcomes like stillbirth is still debated, with some studies showing minimal direct benefit for composite outcomes.
Other comfort measures, such as cool baths and anti-itch creams, may be recommended to manage itching. After delivery, the symptoms of ICP resolve rapidly, with bile acid levels returning to normal within days to weeks. Postpartum, women are advised to have follow-up liver function tests and bile acid checks, around 4 to 12 weeks after birth, to ensure complete resolution. If levels remain elevated, further investigation for other liver conditions may be necessary.