Abdominal Pain During Pregnancy: What It Means

Abdominal pain during pregnancy can occur for many reasons, including normal changes like uterine growth, constipation, or gas. In many cases, the discomfort is mild and may improve with simple measures such as eating fiber-rich foods, staying hydrated, and maintaining light physical activity.

However, abdominal pain during pregnancy can also be linked to more serious conditions, such as ectopic pregnancy, preeclampsia, placental abruption, or miscarriage. These problems may cause additional symptoms like vaginal bleeding, swelling, nausea, or severe pain.

The causes of abdominal pain during pregnancy can vary depending on the stage of pregnancy. Understanding the most common causes in the first, second, and third trimesters, as well as the warning signs that require urgent medical care, helps guide appropriate treatment and monitoring.

First trimester 

The main causes of abdominal pain in the first trimester (weeks 1 to 12 of pregnancy) include:

1. Urinary tract infections

A urinary tract infection (UTI) is a common problem in pregnancy, especially in the first trimester. Typical symptoms include lower abdominal pain, burning or pain with urination (dysuria), difficulty urinating, urinary urgency, fever, and nausea.

What to do: Contact your OB-GYN or midwife as soon as possible so they can order a urine test to confirm the infection. UTIs in pregnancy are usually treated with pregnancy‑safe antibiotics, plus rest and plenty of fluids.

2. Ectopic pregnancy 

An ectopic pregnancy happens when a fertilized egg implants and starts to grow outside the uterus, most often in a fallopian tube.

It is usually detected in the first trimester (often before 10 weeks) and can cause symptoms such as severe one‑sided abdominal pain, pain that worsens with movement, vaginal bleeding, pain during sex (dyspareunia), dizziness, nausea, and vomiting.

What to do: If you suspect an ectopic pregnancy, go to the emergency department immediately so the diagnosis can be confirmed and treatment started as soon as possible.

Management may involve medication (such as methotrexate) or surgery, depending on the size and location of the pregnancy and your overall condition.

3. Miscarriage

A miscarriage, also called a spontaneous abortion, is the loss of a pregnancy before 20 weeks. It can cause symptoms such as lower abdominal pain, vaginal bleeding, and fluid or clots passing from the vagina.

What to do: You should go to the hospital right away so a clinician can examine you and perform tests such as an ultrasound to check the pregnancy and the fetal heart rate.

Depending on the situation, management may include watchful waiting, medicines to help pass the pregnancy tissue, or a minor surgical procedure called dilation and curettage (D&C) to remove remaining tissue.

If a heartbeat is seen and the pregnancy is still viable, your provider will discuss options to monitor and support the pregnancy.

Second trimester

Pain during the second trimester (around weeks 13 to 24 of pregnancy) is most often related to conditions such as:

4. Preeclampsia 

Preeclampsia is a dangerous rise in blood pressure during pregnancy that can threaten the health of both mother and baby. According to the American College of Obstetricians and Gynecologists (ACOG), warning signs include upper abdominal pain, severe headache, and vision changes.

What to do: Contact your OB-GYN or midwife as soon as possible to have your blood pressure checked and start appropriate treatment. In more serious cases, you may need to be admitted to the hospital so that you and your baby can be monitored continuously.

5. Placental abruption

Placental abruption is a serious complication that usually occurs after 20 weeks of pregnancy and can lead to premature birth or pregnancy loss, depending on gestational age. It typically causes sudden, severe abdominal pain, vaginal bleeding, contractions, and lower back pain.

What to do: You should go to the hospital or call your obstetric provider right away for evaluation, including checking the baby’s heart rate and your vital signs.

Treatment may include close monitoring, medicines to help control contractions, and hospital bed rest. In severe cases, early delivery is often necessary for the safety of the mother and the baby.

6. Braxton-Hicks contractions

Braxton-Hicks contractions are “practice” contractions that help the uterus prepare for labor and often start in the second or third trimester, typically after about 20 weeks.

They usually last less than 60 seconds, can occur several times a day, and make the belly feel tight or hard for a short time. Many pregnant people feel little or no pain, while others may notice brief discomfort or pressure low in the abdomen or vagina that goes away on its own.

What to do: If you have Braxton-Hicks contractions, try to stay calm, rest, drink water, and change positions. Lying on your side with a pillow under your belly or between your legs can help you feel more comfortable.

Third Trimester

The main causes of abdominal pain in the third trimester of pregnancy (roughly between weeks 25 and 41) include:

7. Constipation and gas 

Constipation is common in late pregnancy because hormonal changes and the growing uterus slow intestinal movement. This can cause constipation and gas, which may lead to abdominal pain or cramping (often on the left side), discomfort, and a feeling of hardness in the painful area of the abdomen.

What to do: Eat high-fiber foods, such as whole grains, oatmeal, wheat germ, leafy greens, lettuce, watermelon, and papaya. Drink enough fluids to keep your urine light yellow (often around 2 liters of water per day for many adults, unless your doctor has restricted fluids), and aim for at least 30 minutes of physical activity, like walking, on most days of the week.

See your OB-GYN or midwife if your pain does not improve within 24 hours, if you go more than 2 days without a bowel movement, or if you develop other symptoms such as fever or worsening pain. 

8. Round ligament pain

Round ligament pain happens when the ligaments that support the uterus stretch as the belly grows, causing brief, sharp pains in the lower abdomen that can radiate to the groin.

What to do: Sit or lie down and rest in a position that eases the discomfort, such as bending your knees toward your abdomen, or lying on your side with a pillow between your knees and another supporting your belly.

9. Labor pain

Labor pain is the most common cause of abdominal pain at the end of pregnancy and is usually accompanied by cramping, thick vaginal discharge or bloody show, and regular uterine contractions.

What to do: You should go to the hospital or birth center if you think you are in labor, especially if your contractions become regular, stronger, and closer together, or if you have vaginal bleeding or your water breaks.

Some women have contractions that last for several hours and then stop, only to start again the next day. If you are unsure, call your OB provider or labor and delivery unit (L&D) to describe your symptoms and follow their advice on when to come in.

When to go to the hospital

Seek medical care right away if there is persistent pain in the lower right side of the abdomen along with fever, as this can be a sign of appendicitis.

Abdominal pain during pregnancy can sometimes signal a serious problem, especially when it occurs with other warning signs. According to the CDC’s urgent maternal warning signs, abdominal pain with vaginal bleeding, severe headache, swelling, fever, or abnormal vaginal discharge needs immediate medical evaluation.

Call your OB-GYN or midwife right away, or go to the emergency room if they cannot be reached, if any of the following occur:

• Abdominal pain before 12 weeks, with or without vaginal bleeding

• Vaginal bleeding with strong cramping

• Severe headaches

• More than 4 contractions in 1 hour for 2 hours

• Noticeable swelling in the hands, legs, or face

• Pain or difficulty urinating, or blood in the urine

• Fever and chills

• Abnormal vaginal discharge

These symptoms may be linked to serious complications, such as preeclampsia or ectopic pregnancy, and should be assessed urgently by an OB-GYN, midwife, or in the emergency room.