You'll never care (or talk about) this as much as you will when you're a new mum
What it is: Meconium
When: Within the 24 hours after birth
What you need to know: You've probably never seen something as sticky, thick, tar-like and greenish-black as your baby's first poo. Meconium is "what’s been sitting inside the intestines while the baby is forming," says L.E. Wolovits, a general pediatrician at Children’s Medical Center in Dallas and an assistant professor of Pediatrics at UT Southwestern Medical School; it's a combination of amniotic fluid, mucus and cells shed during the baby's development. It's also extremely messy and sticky! Expect to be cleaning up a meconium mess for a while. The good news is that the meconium stage only lasts a few days.