Many women experience diarrhea or frequent watery bowel movements, often within a few hours of taking a meal, during various stages of pregnancy. There is a common misconception that diarrhea or constipation during pregnancy can cause miscarriage , but in truth, it is perfectly normal to have this symptom, especially during the earlier trimesters . Some women also report having diarrhea before labor .
It is one of the earliest symptoms of pregnancy, occurring along with nausea and vomiting (morning sickness)  and food cravings or aversions.
Diarrhea during the third trimester is quite common and is often caused by the same reasons as in the earlier trimesters . Passing watery stool during the later pregnancy weeks may also indicate upcoming labor or a preterm labor . However, having the symptom does not always mean that the baby is coming immediately. Sometimes, it occurs as the body undergoes certain changes in its preparation for labor and delivery.
One or more of the following factors may contribute to cause the problem:
Apart from the above common and relatively harmless causes, upset stomach and diarrhea may also be caused by certain bacterial and viral infections (e.g. listeria, group B streptococcus) of the uterus and placenta.Ectopic pregnancy is another possible cause of painful diarrhea, especially during the first 3 months .
In most cases, it does not cause any harm to the baby. However, severe diarrhea can dehydrate the mother, hampering the blood flow to the fetus. Diarrhea occurring due to some serious pregnancy complications such as abdominal or uterine infections, especially during the second and third trimesters, may also be dangerous for the baby.
Although, it is a common symptom of pregnancy, one should not neglect constant diarrhea as it is one of the most common causes of preterm labor .
Diarrhea occurring due to changes in the diet or a new pregnancy workout schedule generally subsides automatically after a couple of days. In such instances, the following natural remedies help to retain water and electrolytes, preventing dehydration and providing relief from the symptoms. However, they are insufficient for curing any serious underlying conditions causing the diarrhea .
Doctors often suggest certain dietary alterations to manage frequent diarrhea with the BRAT diet (Banana, Rice, Applesauce, Toast)  being commonly recommended. One should opt for whole wheat toast (without butter) and brown rice for better results . Additionally, it is advisable to eat starchy foods to provide the body with vitamins and minerals essential during this time.
Foods to eat
Foods to avoid
The leafy vegetables, diet supplements and prenatal vitamins taken during pregnancy are often responsible for the green coloration of the stools  while black diarrhea is usually caused by iron supplements. So in most cases, there is nothing to worry about in having green or black bowel movements.
Diarrhea continuing for more than 1-2 days should be reported to the doctor, even if the symptoms are mild. Watch out for the following symptoms along with diarrhea: