Why does a pregnant woman experience lower abdominal pain when lying on her left side?

In general, abdominal pain in pregnant women when lying on the left side may be caused by uterine expansion, muscle strain or tension, fetal movement, indigestion, or threatened miscarriage. It is recommended to seek medical attention promptly and receive treatment under a doctor's guidance. Specific explanations are as follows:

1. Uterine Expansion

As pregnancy progresses, the uterus gradually enlarges and may compress surrounding organs and nerves. When lying on the left side, the weight and positional changes of the uterus may intensify this pressure, causing pain. Changing sleeping positions—such as trying right-side lying or supine position—and using a pregnancy pillow to support the lower back and abdomen can help relieve pressure.

2. Muscle Strain or Tension

During pregnancy, abdominal muscles and ligaments stretch due to uterine expansion. Lying on the left side with improper posture may lead to additional stretching of muscles or ligaments, resulting in pain. Gentle abdominal massage, heat or cold therapy, and avoiding strenuous exercise may help alleviate symptoms.

3. Fetal Movement

When a pregnant woman lies on her left side, fetal activity on the left side may become more frequent, potentially stimulating the abdominal wall or internal organs and causing lower abdominal discomfort. No special treatment is required; adjusting sleeping positions or gently stroking the abdomen may soothe the fetus.

4. Indigestion

Hormonal changes during pregnancy may cause indigestion. When lying on the left side, the position and pressure on the gastrointestinal tract may change, leading to abdominal pain, possibly accompanied by nausea, vomiting, bloating, constipation, or diarrhea. Under medical advice, medications such as Bifidobacterium triple viable capsules, Jianwei Xiaoshi tablets, or Hawthorn pills may be used for treatment.

5. Threatened Miscarriage

Being underweight or overweight may increase the risk of threatened miscarriage. Increased uterine sensitivity and more frequent contractions may occur, and lying on the left side might exacerbate contraction-related pain. Symptoms may include vaginal bleeding, lower backache, or soreness. Treatment should follow medical advice and may include medications such as progesterone capsules, dydrogesterone tablets, or Baotai pills.

In daily life, pregnant women should avoid excessive fatigue and strenuous exercise. They may engage in prenatal yoga or mild stretching exercises and should attend regular prenatal checkups.