Liver & GI Diseases in Pregnancy: A Guide
Pregnancy induces significant physiological changes affecting the liver and gastrointestinal system, leading to common conditions like nausea, vomiting, heartburn, and constipation. More severe issues such as hyperemesis gravidarum and obstetric cholestasis can also arise. Understanding these conditions is crucial for effective management, ensuring maternal and fetal health.
Key Takeaways
Pregnancy alters GI function and liver enzymes significantly.
Nausea and vomiting are common, but hyperemesis gravidarum is severe.
Heartburn and constipation are frequent, manageable discomforts.
Obstetric cholestasis is a specific liver disease with fetal risks.
What Physiological Changes Occur in Pregnancy?
Pregnancy brings about numerous physiological adaptations to support fetal development, significantly impacting the gastrointestinal and hepatic systems. Hormonal shifts, particularly increased progesterone, influence gut motility and sphincter tone. The expanding uterus also alters organ positioning. These changes are normal and contribute to many common pregnancy-related symptoms, affecting how the body processes food and manages waste. Key alterations include decreased esophageal pressure, slowed gastric emptying, and changes in liver enzyme levels.
- Decreased lower esophageal pressure.
- Decreased gastric peristalsis and motility.
- Delayed gastric emptying and transit times.
- Decreased serum albumin due to blood volume increase.
- Alkaline phosphatase (ALP) doubles due to placental production.
- ALT, AST, SGOT levels typically fall.
- Bilirubin levels generally remain unchanged.
Why Do Nausea and Vomiting Occur During Pregnancy?
Nausea and vomiting are very common symptoms experienced by pregnant women, particularly in early pregnancy. Often referred to as “morning sickness,” these symptoms can actually occur at any time of day or night. Affecting over half of all pregnant individuals, the onset typically begins around 5-6 weeks into the first trimester. While the exact cause is not fully understood, hormonal fluctuations, especially rising hCG levels, are believed to play a significant role in triggering these uncomfortable sensations.
- Common symptoms in early pregnancy.
- Affects over 50% of pregnant women.
- Onset typically 5-6 weeks in first trimester.
- Nausea, with or without vomiting, occurs any time of day.
What is Hyperemesis Gravidarum and How is it Managed?
Hyperemesis gravidarum represents a severe form of nausea and vomiting in pregnancy, distinct from typical morning sickness due to its intensity and associated complications. It is characterized by intractable vomiting, leading to dehydration, electrolyte imbalances like hypokalemia, and significant weight loss, often exceeding 5% of pre-pregnancy body weight. This condition affects a small percentage of pregnancies, peaking between 8-12 weeks, and can have multifactorial causes. Management focuses on rehydration, correcting electrolyte abnormalities, and antiemetic medications.
- Severe nausea and vomiting in pregnancy.
- Intractable vomiting, dehydration, electrolyte imbalances, weight loss.
- Plasma volume depletion, elevated hematocrit.
- Ketonuria often present.
- Ptyalism (inability to swallow saliva).
- Affects 0.5-2% of pregnancies, peaks 8-12 weeks.
- Multifactorial etiology (hormonal, neurologic, metabolic, psychosocial).
- Symptoms abate by 16-18 weeks, some continue into 3rd trimester.
- Risks: FGR, maternal hyponatremia, thiamine deficiency.
- Rule out other N&V causes (e.g., UTI, Addison disease).
- Investigations: UA, UCX, CBC, LFT, TFT, ultrasound, ketones, electrolytes.
- Hospitalization for intractable emesis, electrolyte issues, severe hypovolemia.
- Management: rehydration, antiemetics, careful fluid selection.
How is Gastro-oesophageal Reflux Managed During Pregnancy?
Gastro-oesophageal reflux, commonly known as heartburn, is a frequent complaint affecting approximately two-thirds of pregnant women, particularly in the third trimester. This discomfort arises from a decreased lower esophageal sphincter tone, primarily due to progesterone's relaxing effects, coupled with altered stomach position and delayed gastric emptying. The reflux of acidic or alkaline gastric contents irritates the esophageal lining, causing pain, waterbrash, and dyspepsia. Management strategies prioritize lifestyle modifications, dietary adjustments, and safe antacid use.
- Common, affecting two-thirds of pregnant women, often in 3rd trimester.
- Caused by decreased lower esophageal sphincter tone (progesterone effect).
- Altered stomach position.
- Decreased gastric peristalsis and delayed emptying.
- Reflux of gastric contents causes inflammation, pain, waterbrash, dyspepsia.
- Management strategies.
What Causes Constipation in Pregnancy and How is it Treated?
Constipation is a common and often uncomfortable symptom experienced during normal pregnancy. It is primarily attributed to reduced colonic motility, a physiological change influenced by hormonal factors like progesterone. Additionally, poor dietary intake, especially if associated with nausea and vomiting, dehydration, and the use of iron supplements, can exacerbate the condition. Effective management focuses on increasing fluid and dietary fiber intake. Laxatives are considered only if initial measures prove insufficient.
- Common symptom of normal pregnancy.
- Likely due to reduced colonic motility.
- Poor diet, dehydration, iron supplements can contribute.
- Management: increase fluids/fiber; laxatives if necessary.
What is Obstetric Cholestasis and Its Implications?
Obstetric cholestasis is a liver disease specific to pregnancy, characterized by intense itching, particularly on the palms and soles, and abnormal liver function tests. While its exact etiology is unknown, it involves incomplete bile acid clearance, possibly due to estrogen's cholestatic effect. This condition typically presents in the third trimester and carries risks such as preterm birth, meconium-stained liquor, and, rarely, intrauterine fetal death. Diagnosis is often one of exclusion, requiring careful differentiation. Management focuses on symptom control and monitoring.
- Pregnancy-specific liver disease: pruritus, abnormal LFTs.
- Prevalence ~0.7% in UK, with geographic variation.
- Unknown etiology, possibly incomplete bile acid clearance (estrogen).
- Risk factors: genetic predisposition, multiple gestations, chronic hepatitis C.
- Presents typically in 3rd trimester (30-32 weeks).
- Symptoms: pruritus (palms/soles), dark urine, pale stool, steatorrhoea.
- Investigations: raised ALT/AST/GAMMA GT, bile acid levels.
- Diagnosis is by exclusion.
- Differential diagnoses: gallstones, viral hepatitis, primary biliary cirrhosis.
- Risks: postpartum haemorrhage, preterm birth, meconium-stained liquor, IUFD.
- Management: counselling, LFT/clotting monitoring, Vitamin K, symptom control.
- Notes: weekly LFTs, unreliable ultrasound/CTG for fetal death, continuous fetal monitoring in labor.
Frequently Asked Questions
What are the most common gastrointestinal issues in pregnancy?
Common gastrointestinal issues during pregnancy include nausea and vomiting, often called "morning sickness," and heartburn (gastro-oesophageal reflux). Constipation is also a very frequent complaint. These are largely due to hormonal changes and the physical effects of the growing uterus.
How does pregnancy affect liver function?
Pregnancy causes physiological changes in liver function, such as increased alkaline phosphatase (ALP) from the placenta and decreased ALT/AST. Serum albumin may fall due to dilution. Bilirubin levels typically remain stable. These changes are usually normal adaptations, but significant deviations warrant investigation.
When should severe nausea and vomiting be a concern?
Severe nausea and vomiting, known as hyperemesis gravidarum, is a concern when it leads to dehydration, significant weight loss (over 5%), and electrolyte imbalances. If oral intake is not tolerated or symptoms are intractable, medical evaluation and potentially hospitalization are necessary.
