After pains are the name given to contractions that occur after labor and you have given birth. These contractions signal the process of involution, the process of your uterus shrinking back down to its prepregnancy size and shape. They are not a cause of concern.
Your uterus has spent the last nine months of pregnancy growing nearly twenty-five times its original size. The contractions after the birth help it shrink back down in about four to six weeks.
While after pains are not a reason to worry, they can cause discomfort or even pain. Some mothers will notice them more than others, particularly if this is not your first baby. Some say that the after pains increase after each subsequent baby, though not everyone reports this to be true. For pain, you can use comfort measures like warm packs (with your practitioner's approval), massage of the fundus through your abdomen, and certain medications (Ibuprofen works well for most women.).
You may notice these contractions most intensely in the first few days after giving birth. You may also notice them more when you nurse or breastfeed. This happens because the uterus is still sensitive to the oxytocin released while nursing. Some mothers find that trying to ensure they are using their comfort measures or medications immediately before breastfeeding can ease the discomfort while nursing.
Do not be concerned if you do not feel after pains. Not every mother feels them. This does not mean that your uterus is not healing. Ask your postpartum nurse to help you learn to feel your uterus, then you can check it's progress for awhile to reassure yourself.