What is Constipation During Pregnancy?

It refers to irregular bowel movements that many women experience during pregnancy, often accompanied by symptoms such as bloating, stomach discomfort, difficulty passing stools, and hard stools, which can cause extreme physical discomfort for pregnant women.

It typically appears in the second to third month of pregnancy alongside rising progesterone levels and may worsen as the uterus grows in size.

Which Department Should Be Consulted for Constipation During Pregnancy?

English Name: Constipation During Pregnancy.

Aliases: Pregnancy-related constipation, gestational constipation, maternal gastrointestinal adaptive changes during pregnancy, pregnant women's constipation.

Departments to Visit: Obstetrics and Gynecology, Gynecology, Gastroenterology.

What Causes Constipation During Pregnancy?

1. Constipation during pregnancy is mainly caused by hormonal changes affecting small intestine and colon motility. Increased progesterone levels play a key role in reducing colon smooth muscle activity, inhibiting the intensity and frequency of spontaneous colon muscle movements, leading to prolonged intestinal transit time.
2. Other factors may also contribute to delayed intestinal transit, such as decreased plasma motilin (a stimulatory gastrointestinal hormone) during pregnancy and mechanical obstruction of small intestine movement by the growing uterus, especially in the third trimester.
3. Pregnancy-related factors (e.g., bed rest, iron or calcium supplementation) may also trigger constipation.
4. The causes of constipation in pregnant women may overlap with those in the general population. For details, refer to the "Constipation" topic.

Who Is Prone to Constipation During Pregnancy?

Pregnant women, with symptoms typically starting in the second or third month of pregnancy, peaking in the eighth month, and gradually resolving after childbirth.

What Are the Symptoms of Constipation During Pregnancy?

Pregnant women experience fewer bowel movements than usual (commonly defined as fewer than three spontaneous bowel movements per week, though this may not apply to everyone), straining during defecation, a sense of incomplete evacuation, anal blockage, lumpy or hard stools, stronger odor, and darker color.

Prolonged single bowel movements, infrequent loose stools without laxatives, and some may require manual assistance (e.g., using fingers, soap, or enemas).

Post-defecation symptoms may include lower back and inner thigh muscle soreness. Rarely, prolonged squatting may lead to fainting. Swelling or pain around the anus may occur after passing stools.

Accompanied by bloating, excessive flatulence, and sometimes stomach pain.

How Is Constipation During Pregnancy Diagnosed?

Clinical diagnosis is based on typical constipation symptoms, usually without additional tests.

If other abnormal symptoms (e.g., bloody stools, weight loss, or anemia) are present, medical evaluation is recommended to determine the cause and treatment.

How Is Constipation During Pregnancy Treated?

After clinical diagnosis, empirical treatment includes increasing dietary fiber and fluid intake or using bulk-forming laxatives as the first-line option (e.g., psyllium fiber, methylcellulose, calcium polycarbophil, and wheat dextrin, as these are not absorbed by the body).

• Most cases require tailored medication plans under the guidance of physicians, obstetricians, or gastroenterologists.
• Increasing dietary fiber intake can alleviate constipation. Natural fiber sources (pears, prunes, bamboo shoots, etc.) or fiber supplements (inexpensive, convenient, and safe) are often preferred.

What Is the Prognosis for Constipation During Pregnancy?

In most cases, it is temporary and resolves with minimal or no treatment.

Rarely, prolonged constipation may lead to fecal impaction, requiring enemas or medical intervention.

Chronic laxative use may disrupt bowel motility, worsening constipation. Severe cases may cause electrolyte imbalances or fluid disorders, posing risks for pregnant women with diabetes or kidney disease. Straining or hard stools can also trigger or aggravate hemorrhoids.

How to Prevent Constipation During Pregnancy?

1. Understand that daily bowel movements are not mandatory. Reduce reliance on laxatives by adjusting diet (e.g., increasing water and fiber intake).
2. For excessive laxative/enema use, gradually reduce dosage under medical supervision while adopting alternative methods to improve bowel movements.
3. Defecate after meals to leverage postprandial colon motility, especially in the morning when contractions are strongest.
4. Engage in moderate daily exercise (e.g., aerobic or strength training for 30 minutes, 5–7 days/week; aim for 6,000 steps/day) to reduce constipation.
5. Foods like beans, citrus fruits, apples, prunes, peaches, pears, cherries, grapes, and nuts aid bowel movements. Recommended daily fiber intake: 20–35g (check food nutrition labels or apps for guidance).
6. Preconception and pregnancy diets should include iron and calcium to minimize medication needs. If calcium supplements are required, citrate forms are less likely to cause constipation than carbonate.