According to Parents, a fetus does not typically have bowel movements in the womb. If this happens before or during birth, the baby needs to be observed carefully in case any complications occur.
WebMD indicates that a baby's first bowel movements usually happen within the first three days following birth. These waste products are referred to as "meconium," and they are very dark and sticky.
Parents magazine describes a scenario where a fetus takes in meconium through its mouth or lungs while still in the uterus or during birth. This sometimes leads to Meconium Aspiration Syndrome, which needs to be treated but often is not a serious condition.