Pregnant women who have black stools may have consumed blood products or used iron supplements, or there may be diseases such as peptic ulcers that cause bleeding, and these conditions may lead to the appearance of black stools. Pregnant women who have recently consumed blood products or used iron supplements, such as ferrous succinate, due to the high content of iron, the unabsorbed iron generates black ferrous sulfide under the action of gastric acid and intestinal bacteria, resulting in black stool color. After stopping the consumption of blood products and iron supplements, the black stools will gradually disappear. If a pregnant woman suffers from peptic ulcer, ruptured esophagogastric fundic varices and other diseases, there may be digestive bleeding, the blood into the intestinal lumen, because the blood also contains a large amount of iron, it may also generate black ferrous sulfide, showing black stool color. There may be other reasons why pregnant women have black stools, so it is recommended that you seek medical attention in a timely manner, complete the relevant examinations, and clarify the causes under the guidance of a professional doctor, so as to avoid delays in the condition.