| Differential diagnosis | Typical clinical presentation | Distinguishing features |
| Pregnancy-specific causes of pruritus | ||
| Pruritus gravidarum | Pruritus, usually in the third trimester | Similar presentation to intrahepatic cholestasis of pregnancy, but normal liver function tests and bile acids |
| Atopic eruption of pregnancy | Pruritus, usually in the first trimester | Dry, red rash with or without small blisters Typically affects trunk and limb flexures |
| Polymorphic eruption of pregnancy | Pruritus, usually in the third trimester | Typically affects lower abdominal striae with umbilical-sparing Urticarial papules or plaques, vesicles, and target lesions |
| Pemphigoid gestationis | Itchy rash, usually in the second or third trimester | Rare autoimmune condition characterized by complement-fixing immunoglobulin G antibodies Rash develops into large, tense blisters Associated with increased risk of preterm delivery and SGA Recurs in subsequent pregnancies and with combined oral contraceptive |
| Prurigo of pregnancy | Pruritus, usually in the third trimester | Groups of red-brown papules on the abdomen and extensor surfaces of the limbs Papules may persist postpartum |
| Pruritic folliculitis of pregnancy | Pruritus, usually in the third trimester | Acneiform eruption on the shoulders, upper back, thighs, and arms Follicular papules and pustules, which may be filled with pus, but culture is typically sterile; rash usually improves with advancing gestation |
| Preexisting causes of pruritus | ||
| Atopic dermatitis | Pruritus, any gestation | History of atopy |
| Allergic or drug reaction | Pruritus, any gestation | History of exposure to allergen or drug Maculopapular rash |
| Systemic disease | History of liver, renal, or thyroid disease | Signs and symptoms of systemic disease History of pruritus before conception |
| Pregnancy-specific causes of hepatic impairment | ||
| Acute fatty liver of pregnancy | Nausea, vomiting, headache, abdominal pain, polyuria, polydipsia in the third trimester | New nausea and vomiting in the third trimester are not caused by hyperemesis gravidarum Women with AFLP are more unwell and often have associated renal impairment, coagulopathy, hypoglycemia, and preeclampsia |
| Hemolysis, elevated liver enzymes and low platelets syndrome | Hypertension, proteinuria, headache, epigastric pain, visual disturbance in the second or third trimester | Hypertension and proteinuria are predominant features |
| Hyperemesis gravidarum | Nausea and vomiting in the first trimester | Presentation in early pregnancy, abnormal liver function test resolves with successful treatment |
| Preexisting causes of hepatic impairment | ||
| Viral hepatitis | Jaundice, nausea, vomiting, abdominal pain | Systemic symptoms, generally unwell, contacts |
| Primary biliary cirrhosis or primary sclerosing cholangitis | Pruritus, jaundice, lethargy, other autoimmune disorders | Symptoms before pregnancy; associated autoantibodies |
| Autoimmune hepatitis | Nausea, lethargy, jaundice, other autoimmune disorders | Symptoms before pregnancy; associated autoantibodies |
| Drug-induced liver injury | Pruritus, jaundice | Ingestion of drugs before onset of symptoms or biochemical abnormalities |
| Biliary obstruction | Abdominal pain, pale stools, dark urine | Liver ultrasound scan abnormalities |
| Venoocclusive disease | Abdominal pain, distension (ascites), jaundice, gastrointestinal bleeding | Thrombosis demonstrated on imaging, thrombophilia |
