GI disorders are some of the most frequent complaints during pregnancy. Some women have certain GI disorders that are unique to pregnancy. Other pregnant patients present with chronic GI disorders that require special consideration during pregnancy. Understanding the presentation and prevalence of various GI disorders is necessary in order to optimize care for these patients.

Incidence

Nausea, with or without vomiting, is common in early pregnancy. Nausea occurs in 50-90% of pregnancies, while vomiting is an associated complaint in 25-55% of pregnancies.

Risk factors

Risk factors include youth, obesity, first pregnancy, and smoking. Nausea tends to recur in subsequent pregnancies, although it may be shorter in duration.

Clinical features

Nausea is usually self-limiting and occurs in 91% of women in the first trimester, generally in the first 6-8 weeks. In its mild form, nausea is known as morning sickness. The pathophysiology is debatable. It has been attributed to hormonal fluctuations, GI motility disorders, and psychosocial factors. Persistence of nausea and vomiting into the second or third semester should prompt a search for other causes.

Other causes include urinary tract infections, gastroenteritis, peptic ulcer disease (PUD), pancreatitis, biliary tract disease, hepatitis, appendicitis, adrenal insufficiency, and increased intracranial pressure. In later pregnancy, other considerations include hydramnios, preeclampsia, and onset of labor.

Treatment

The severity of symptoms dictates the therapy. Mild symptoms can be managed by reassurance, avoidance of precipitating factors, and changes in diet (eg, smaller, more frequent meals; increased carbohydrate intake; low fat intake).

For more severe and intractable symptoms, pharmacotherapy with antiemetics can be offered. Meclizine (class B) or promethazine (class C) can be used. Adverse effects to the human fetus have not been reported; however, meclizine and promethazine are not recommended for routine use in pregnancy.

Metoclopramide (class B) can be used in pregnancy. It has not been shown to induce teratogenic effects, but it crosses the placenta and produces substantial fetal blood alcohol effects.

Data on the harmful fetal effects of other antiemetics (eg, prochlorperazine [class C], diphenhydramine [class C], trimethobenzamide) preclude their use in pregnancy. Pyridoxine (vitamin B-6) is an alternative therapeutic agent in patients with severe nausea or vomiting.

Prognosis

The prognosis for the mother and child is generally good. In fact, women with mild nausea and vomiting in pregnancy have better pregnancy outcomes compared to women without these symptoms.

Hyperemesis gravidarum is characterized by intractable nausea and vomiting that occurs in early pregnancy, leading to fluid and electrolyte imbalance. It may be considered the severe end of the spectrum of nausea and vomiting in pregnancy.

Incidence

Hyperemesis gravidarum occurs in 3-10 cases per 1000 pregnancies.

Pathogenesis

Pathogenesis is poorly understood. Hormonal and psychological factors may play a role.

Clinical features

The condition occurs early in the first trimester, usually in weeks 4-10. Symptoms usually resolve by weeks 18-20.

• Intractable vomiting   Ptyalism

•      Weight loss - More than 5% of body weight

•       Malnutrition (possible)

•      Abdominal pain (not common)

•       Ketosis, hypokalemia, and metabolic alkalosis (possible)

•      Abnormal liver enzyme levels (possible)

•       Mild hyperthyroidism (possible)

Risk factors

• Obesity

• Nulliparity

• Multiple gestations

• Trophoblastic disease

Treatment

Replenish fluids, electrolytes, vitamins, and minerals. Thiamine supplementation is recommended for women who have had vomiting for more than 3 weeks. Avoid environmental triggers.

Dietary management

Patients should eat frequent, small, high-carbohydrate, low-fat meals. Gut rest may be needed in some cases. Parenteral or enteral nutrition can be beneficial in some cases.

Medications

Antiemetics and pyridoxine can be used. Corticosteroids have been tried in severe and refractory cases.

Prognosis

Prognosis is good. No differences in birth weight or birth defects have been observed in pregnancies affected by hyperemesis gravidarum.

Incidence

Gastroesophageal reflux disease (GERD), commonly known as heartburn, is common in pregnancy and is experienced by 45-80% of pregnant women. Fifty-two percent of pregnant women first experience heartburn in the first trimester; 24-40% experience it in the second trimester, and 9% experience it in the third trimester.

Pathogenesis

Both mechanical and intrinsic factors are involved. Abnormal esophageal motility, decreased lower esophageal sphincter (LES) pressure, and increased gastric pressure contribute to GERD in pregnancy. Increased intra-abdominal pressure from the gravid uterus and displacement of the LES also play roles.

Clinical features

Clinical presentation is similar to that for the general population. Heartburn and regurgitation are the cardinal symptoms. Diagnostic evaluation consists of a thorough history and physical examination. Diagnostic studies are rarely needed. Endoscopy may be indicated in patients with complications of GERD. Twenty-four–hour ambulatory pH studies can be useful in patients with atypical presentations (eg, cough, wheezing, sore throat) and refractory symptoms.

Treatment

• Lifestyle modifications: These are the first line of management. Advise patients to take the following measures:

Elevate the head of the bed.

o        Avoid bending or stooping positions.

o        Eat small, frequent meals.

o        Refrain from ingesting food (except liquids) within 3 hours of bedtime.

• Nonsystemic medications: Antacids or sucralfate are safe in pregnancy because they are not systemically absorbed. Antacids may interfere with iron absorption.
  
•   Systemic gastric antisecretory medications: Histamine 2 (H2) blockers are preferred over proton pump inhibitors because more data are available on the safety of H2 blocker use in pregnancy. Cimetidine, ranitidine, and famotidine can be used in pregnancy (class B drugs). They can cross the placental barrier. Lansoprazole is the preferred proton inhibitor in pregnancy (class B).

Prognosis

Outcome for pregnant patients with GERD is good. GERD tends to recur with subsequent pregnancies.

Pregnancy is associated with increased risk of gallstone formation. Gallstones are an important cause of pancreatitis in pregnancy. Cholecystectomy is the second most common nonobstetric surgical procedure in pregnancy after appendectomy.

Incidence

Thirty-one percent of women develop sludge during pregnancy, and 2% develop new gallstones. Risk is highest in the second or third trimester and postpartum.

Pathogenesis

The exact mechanism is not known. Possible factors are increased lithogenicity of bile, increased stasis of bile, and decreased gall bladder emptying.

Clinical features

• Right upper quadrant pain

• Epigastric pain

• Fever


• Vomiting


• Jaundice


• Tenderness in right upper quadrant - May be difficult to elicit because of an enlarged uterus


• Pancreatitis

Treatment

Severe biliary colic can be managed conservatively with hydration, narcotics, antibiotics, and dietary modifications. Endoscopic retrograde cholangiopancreatography may be needed in cases of cholangitis, biliary obstruction, or pancreatitis.

Cholecystectomy is indicated in the presence of persistent or recurrent symptoms, significant nutritional compromise, and weight loss. This is required in fewer than 0.1% of cases. The second trimester is the best period for surgery.

Incidence

PUD is uncommon during pregnancy. The reported incidence rate is 0.005%, although this is probably underestimated. PUD is believed to improve during pregnancy because of the decreased gastric acid secretion that occurs in pregnancy.

Risk factors

These include smoking, alcoholism, stress, socioeconomic status, and prior history of PUD or Helicobacter pylori gastritis. Nonsteroidal medications are not a common risk factor for PUD in pregnancy.

Clinical features

Clinical features are similar to the nonpregnant state. Symptoms include dyspepsia, epigastric pain, nausea, vomiting, and heartburn. GI bleeding and perforation are rare complications of PUD in pregnancy.

Treatment

H2-receptor antagonists (eg, cimetidine, ranitidine, famotidine) are the first choices of treatment. Treatment for H pylori gastritis should be initiated after the pregnancy and breastfeeding because some of the recommended medications are relatively contraindicated in pregnancy. Lansoprazole has been reported to be safe in pregnancy.

Prognosis

PUD does not cause increased maternal or fetal morbidity and mortality.

Incidence

Diarrhea occurs in up to 34% of pregnant women.

Etiology

Causes mirror those of the nonpregnant state. The most common causes are infectious agents (eg, Salmonella, Shigella, and Campylobacter species; Escherichia coli; protozoans; viruses). Food poisoning, medications, and irritable bowel syndrome are other common causes. Exacerbations of inflammatory bowel disease can also occur in pregnancy.

Evaluation

Conduct a routine evaluation with stool studies for bacterial culture, ova, parasites, fecal leukocytes, and stool assay for Clostridium difficile infection. For persistent diarrhea, flexible sigmoidoscopy can be performed. Flexible sigmoidoscopy is safe in pregnancy.

Treatment

Conservative management is the mainstay of treatment.

• Administer fluid replacements.


•   Administer medications to control the diarrhea, if needed. Nonsystemic medications should be tried first.


•      Treat the underlying cause


•     Treat patients with irritable bowel syndrome as follows:  

o Administer stool-bulking agents.

o Institute a high-fiber diet.

o  Anticholinergics/antispasmodics are not recommended.

o Avoid antidepressants.

Incidence

The incidence rate of constipation in pregnancy is 11-38%.

Etiology

The etiology is multifactorial. Possible factors include the following:

• Decreased small bowel motility

•   Decreased motilin level

•   Decreased colonic motility


• Increased absorption of water


• Iron supplementation

Evaluation

Extensive evaluation is seldom warranted. Evaluation should include a careful history, presence of preexisting constipation, dietary habits, current medications, and use of laxatives. Perform a digital rectal examination to exclude fecal impaction.

The results of blood studies can be useful to exclude hypothyroidism, diabetes mellitus, hypercalcemia, and hypokalemia as possible causes.

If rectal bleeding is present, anoscopy or flexible sigmoidoscopy can be performed to exclude anorectal lesions.

Treatment

Conservative treatment is the mainstay of therapy.

• Dietary changes

• Increased physical activity

• Kegel exercises (may be useful)

• Bulking agents, eg, psyllium (safe in pregnancy)

Medications

Few data are available on safety and efficacy in pregnancy. Stool softeners such as sodium docusate are probably safe. Stimulant laxatives are probably safe for intermittent use but should not be used regularly. Castor oil and mineral oil should not used in pregnancy.