The third trimester refers to the last three months of pregnancy, lasting from weeks 29 to 40. As the fetus continues to grow and develop and turn itself head-down in preparation for delivery, most expectant mothers experience several uncomfortable symptoms, such as diarrhea.
Diarrhea during the third trimester is common and is more likely to occur close to the due date. The chemical prostaglandin is released as labor nears, causing the uterus to contract and also resulting in diarrhea.
Diarrhea in the third trimester can be sign labor is coming, but it’s not the only sign. If you have diarrhea and these other symptoms, it may be a sign you are entering labor:
- The baby has dropped and you feel it is easier to breathe (you may also feel increased pressure on the bladder)
- The bloody show, as the mucus plug is expelled
- Your water breaks
- A burst of energy and sense of urgency to get things done
- Cervix will thin and stretch (effacement) and open (dilation)
- Your doctor will check this
- Consistent contractions
If you think you are going into labor, contact your doctor.
If diarrhea is not due to labor, most of the time it is nothing to worry about and it will go away on its own. Drink plenty of water to stay hydrated, juice for potassium, and broth for sodium.
See a doctor about diarrhea in the third trimester if:
- Diarrhea lasts more than two days
- There is blood in the stool
- It is accompanied by a fever
- You suspect food poisoning such as listeriosis, which can pass through the placenta and put the baby at risk
What Are Common Symptoms of the Third Trimester of Pregnancy?
Some symptoms that started earlier in pregnancy, such as nausea, fatigue, and morning sickness, usually improve but may continue into the third trimester for some people.
Common symptoms of the third trimester of pregnancy include:
- Difficulty taking deep breaths as the fetus crowds the abdominal cavity
- Difficulty getting comfortable at night for sleep
- Increased skin temperature and feeling hot, like the fetus, radiates body heat
- Increased urinary frequency due to increased pressure on the bladder
- Fluid retention (edema) that may cause swelling of the ankles, hands, fingers, and face
- If swelling is sudden or extreme, or if you gain a lot of weight quickly, talk to your doctor right away as this could be a sign of preeclampsia, a serious complication of pregnancy in which high blood pressure (hypertension) and evidence of organ injury develops in a pregnant woman after 20 weeks of pregnancy
- More frequent leg cramps
- Decreased blood pressure due to the fetus pressing on the main vein that returns blood to the heart
- Hair growth on the arms, legs, and face due to hormones
- Hair may feel more coarse
- The belly button may stick out
- Stretch marks can appear on the abdomen, breasts, buttocks, and thighs
- Dry, itchy skin, especially on the belly as the baby grows, stretches the skin
- Increased sex drive
- Dark patches of skin on the face
- Constipation
- Heartburn/indigestion
- Hemorrhoids
- Worsening backaches
- Varicose veins in the legs
- Increased white-colored vaginal discharge (leukorrhea), which may contain more mucus
- Breast tenderness
- The baby moving lower in the abdomen (dropping)
- Fluid may begin to leak from the nipples (called colostrum, which is a milky fluid produced just before breast milk)
- False labor (Braxton-Hicks contractions) may occur at irregular intervals in preparation for childbirth
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https://www.hopkinsmedicine.org/health/wellness-and-prevention/the-third-trimester
https://www.womenshealth.gov/pregnancy/youre-pregnant-now-what/stages-pregnancy
https://americanpregnancy.org/healthy-pregnancy/labor-and-birth/signs-of-labor/
https://americanpregnancy.org/healthy-pregnancy/is-it-safe/diarrhea-in-pregnancy/
https://www.todaysparent.com/pregnancy/pregnancy-health/dealing-with-diarrhea-during-pregnancy/