Some women tend to poop along side when giving birth due to pushing and other pressures of labor. Most women feel disgusted when this happens to them but however, scientist have actually seen this as beneficial, that pooping on babies when giving birth is a great way of introducing gut bacteria into the baby who tend not to have them naturally. Gut bacteria are normal flora "microbiome", they are bacteria that pose no threat to humans and other animals, they are very useful in improving ones immunity, digestion, and they help in fighting against other harmful micro-organisms, preventing them from causing diseases.
This bacteria are not found in new born babies, it need to be introduced into them. Research shows that babies get exposed to these helpful bacteria when coming out of the mother's vagina canal, and also the mother pooping during birth may also help the baby to pick up some important gut bacteria that is lacking in the baby.
