Pregnancy as a Cause of Pancreatitis
Pregnancy itself does not directly cause pancreatitis, but it creates a physiological environment that significantly increases the risk of pancreatitis through two primary mechanisms: gallstone formation and hypertriglyceridemia. 1, 2, 3
Understanding the Pathophysiology
Pregnancy is not an independent cause of pancreatitis but rather acts as a precipitating factor in susceptible women through specific metabolic changes:
Hypertriglyceridemia-Mediated Risk
Pregnancy induces a "physiological hyperlipidemia" with 2-fold increases in circulating triglyceride levels during the third trimester due to enhanced lipolytic activity in adipose tissue. 1
Women with baseline triglyceride levels ≥500 mg/dL may develop severe hypertriglyceridemia during the third trimester, creating substantial pancreatitis risk. 2
Both insulin resistance and hyperestrogenemia represent causative factors for the development or amplification of hypertriglyceridemia during pregnancy and may present a therapeutic challenge, especially if pancreatitis develops. 1
The concept of pancreatitis caused by pregnancy per se is not valid, although in susceptible women with lipid disorders, hypertriglyceridemia can occur and serve as an etiologic factor. 3
Gallstone-Mediated Risk
Hormonal changes in pregnancy lead to decreased gallbladder motility and lithogenic bile, with gallstones occurring in up to 10% of pregnancies. 1
Changes in hepatobiliary function during pregnancy create a lithogenic environment through gallbladder stasis and secretion of bile with increased cholesterol and decreased chenodeoxycholic acid. 3
Gallstones are the most common cause of pancreatitis in pregnancy, accounting for the majority of cases. 4, 3, 5
Clinical Epidemiology
Acute pancreatitis complicates approximately 0.07% of pregnancies. 5
The estimated incidence of gallstone-related disease complicating pregnancy is 0.5% to 0.8%. 1
Gallstones account for pancreatitis in the majority of pregnant patients, followed by hypertriglyceridemia, while alcohol is unusual as a cause in contrast to nonpregnant women. 3, 6, 5
Risk Stratification Algorithm
Identify High-Risk Patients
High-risk women, including those with poorly controlled diabetes mellitus, should have triglyceride levels checked once every trimester. 2
Monthly monitoring should be initiated when fasting triglycerides exceed 250 mg/dL. 2
Women with preexisting gallstones, obesity (high prepregnancy BMI), or elevated serum leptin levels are at increased risk. 1
Critical Thresholds
Triglyceride levels ≥500 mg/dL significantly increase pancreatitis risk, with risk increasing proportionally at higher levels. 7
Only 10% of pancreatitis cases overall are a direct consequence of triglyceride levels, but this proportion is higher in pregnancy. 1
Common Pitfalls to Avoid
Do not delay intervention until pancreatitis develops, as maternal mortality from gestational hypertriglyceridemic pancreatitis approaches 20%. 2
Do not assume pregnancy alone causes pancreatitis—always investigate underlying gallstone disease or lipid disorders. 3, 6
Do not use low-fat, high-carbohydrate diets without carbohydrate restriction, as excessive carbohydrates are converted to triglycerides. 2
Do not overlook the high relapse rate (72%) in gallstone pancreatitis patients before delivery if definitive treatment is not performed. 5
Key Clinical Distinction
The critical distinction is that pregnancy does not independently cause pancreatitis but rather unmasks or exacerbates underlying conditions (gallstones, lipid disorders) that then lead to pancreatitis. 3, 6 This is similar to how pregnancy unmasks underlying clotting disorders in Budd-Chiari syndrome—pregnancy alone is unlikely to cause the condition but often reveals a predisposing factor. 1