It is generally recommended to wait a year after giving birth before getting pregnant again. The body, more specifically - the uterus, needs to time to recover and heal after giving birth. If anything is entered into the vagina before the uterus is healed, an infection could occur. Many physicians ask that women hold off on having sex until at least six weeks post partum. If you become pregnant before the uterus is healed, aside from an infection, there is a possible risk of a miscarriage.

There are other possible complications when becoming pregnant too soon, such as, the risk for ruptured uterus or having a premature and low weight baby. Again, these are only possible complications and do not happen to everyone. I had a friend who became pregnant within a few months of giving birth and her only problem was that her bladder was extremely weak (beyond the norm that you would expect for a pregnant person).

In all reality, it depends on the person and how well they heal both emotionally and physically and whether they are ready. It also depends on your doctor, as they all have different recommendations based on age and health. For instance, I had major complications towards the end of my pregnancy and my doctor recommended I wait more than a year before becoming pregnant again.