Hepatic disorders in pregnancy may be
Unique to pregnancy
Preexisting
Coincident with pregnancy and possibly exacerbated by pregnancy
Jaundice
Jaundice may result from nonobstetric or obstetric conditions.
Nonobstetric causes of jaundice include
Acute viral hepatitis (most common)
Biliary obstruction by gallstones
Gallstones appear to be more common during pregnancy, probably because bile lithogenicity is increased and gallbladder contractility is impaired.
Obstetric causes of jaundice include
Hyperemesis gravidarum (usually causing mild jaundice)
Both cause hepatocellular injury and hemolysis.
Acute viral hepatitis
The most common cause of jaundice during pregnancy is acute viral hepatitis. Pregnancy does not affect the course of most types of viral hepatitis (A, B, C, D); however, hepatitis E may be more severe during pregnancy.
Acute viral hepatitis may predispose to preterm delivery but does not appear to be teratogenic.
Hepatitis B virus may be transmitted to the neonate immediately after delivery or, less often, to the fetus transplacentally. Transmission is particularly likely if women are e-antigen–positive and are chronic carriers of hepatitis B surface antigen (HBsAg) or if they contract hepatitis during the 3rd trimester. Affected neonates are more likely to develop subclinical hepatic dysfunction and become carriers than to develop clinical hepatitis. All pregnant women are tested for HBsAg to determine whether precautions against vertical transmission are needed (prenatal prophylaxis with immune globulin and vaccination for neonates exposed to hepatitis B virus).
Chronic hepatitis
Chronic hepatitis, especially with cirrhosis, impairs fertility. When pregnancy occurs, risk of spontaneous abortion and prematurity is increased, but risk of maternal mortality is not.
Intrahepatic cholestasis (pruritus) of pregnancy
This relatively common disorder apparently results from idiosyncratic exaggeration of normal bile stasis due to hormonal changes. Incidence varies based on ethnicity and is highest in Bolivia and Chile.
Consequences of intrahepatic cholestasis include increased risk of
Passage of stool (meconium) by the fetus before birth, which can lead to meconium aspiration syndrome
Intense pruritus, the earliest symptom, develops during the 2nd or 3rd trimester; dark urine and jaundice sometimes follow. Acute pain and systemic symptoms are absent. Intrahepatic cholestasis usually resolves after delivery but tends to recur with each pregnancy or with use of oral contraceptives.
Intrahepatic cholestasis is suspected based on symptoms. The most sensitive and specific laboratory finding is a fasting total serum bile acid level of > 10 mmol/L. This finding may be the only biochemical abnormality present. Fetal demise is more likely when the fasting total bile acid level is > 40 mmol/L.
1)
For patients with total bile acid levels < 100 micromol/L, delivery at 36 to 39 weeks gestation or at diagnosis if diagnosed at > 39 weeks
For patients with total bile acid levels ≥ 100 micromol/L, delivery at 36 weeks gestation or at diagnosis if diagnosed later
Fatty liver of pregnancy
This rare, poorly understood disorder occurs near term, sometimes with preeclampsia. Patients may have an inherited defect in mitochondrial fatty acid beta-oxidation (which provides energy for skeletal and cardiac muscle); risk of fatty liver of pregnancy is 20 times higher in women with a mutation affecting long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD), particularly the G1528C mutation on one or both alleles (autosomally inherited).
Symptoms of fatty liver include acute nausea and vomiting, abdominal discomfort, and jaundice, followed in severe cases by rapidly progressive hepatocellular failure. Maternal and fetal mortality rates are high in severe cases.
A seemingly identical disorder may develop at any stage of pregnancy if high doses of tetracyclines are given IV.
Clinical and laboratory findings resemble those of fulminant viral hepatitis except that aminotransferase levels may be < 500 units/L and hyperuricemia may be present.
Diagnosis of fatty liver of pregnancy is based on
Clinical criteria
Liver tests
Hepatitis serologic tests
Liver biopsy
Biopsy shows diffuse small droplets of fat in hepatocytes, usually with minimal apparent necrosis, but in some cases, findings are indistinguishable from viral hepatitis.
Affected women and their infants should be tested for known genetic variants of LCHAD.
Depending on gestational age, prompt delivery or termination of pregnancy is usually advised, although whether either alters maternal outcome is unclear. Survivors recover completely and have no recurrences.
Preeclampsia
Severe preeclampsia can cause liver problems with hepatic fibrin deposition, necrosis, and hemorrhage that can result in abdominal pain, nausea, vomiting, and mild jaundice.
Subcapsular hematoma with intra-abdominal hemorrhage occasionally occurs, most often in women with preeclampsia that progresses to the HELLP syndrome (hemolysis, elevated liver enzymes, and low platelet count). Rarely, the hematoma causes the liver to rupture spontaneously; rupture is life threatening, and pathogenesis is unknown.
Chronic hepatic disorders
Pregnancy may temporarily worsen cholestasis in primary biliary cirrhosis and other chronic cholestatic disorders, and the increased plasma volume during the 3rd trimester slightly increases risk of variceal hemorrhage in women with cirrhosis. However, pregnancy usually does not harm women with a chronic hepatic disorder.
Cesarean delivery is reserved for the usual obstetric indications.
General reference
1. American College of Obstetricians and Gynecologists’ Committee on Obstetric Practice, Society for Maternal-Fetal Medicine. Medically Indicated Late-Preterm and Early-Term Deliveries: ACOG Committee Opinion, Number 831. Obstet Gynecol 138(1):e35-e39, 2021. doi:10.1097/AOG.0000000000004447
Key Points
In pregnant women, hepatic disorders may be related or unrelated to the pregnancy.
The most common cause of jaundice during pregnancy is acute viral hepatitis.
Pregnancy does not affect the course of most types of viral hepatitis (A, B, C, D), but hepatitis E may be more severe during pregnancy.
Hepatitis B virus may be transmitted to the neonate immediately after delivery or, less often, to the fetus transplacentally; test all pregnant women for HBsAg to determine whether precautions against vertical transmission are needed.
Intrahepatic cholestasis of pregnancy causes intense pruritus and increases risk of fetal prematurity, stillbirth, and respiratory distress syndrome.
Fatty liver of pregnancy occurs near term, sometimes with preeclampsia; because maternal and fetal mortality rates can be high in severe cases, prompt delivery or termination of pregnancy is usually advised.
Usually, pregnancy does not harm women with a chronic hepatic disorder.