What is normal time gap between two pregnancies of human?

Answer 1

A woman can get pregnant the first time she ovulates after giving birth. This is rarely less than six weeks, and if she is breastfeeding her infant, this usually serves to delay her next ovulation until the baby is weaned.

In most nomadic societies, a woman's pregnancies are close to four years apart. This occurs naturally, and it is believed that the extended period of time for which women in most such societies breastfeed their children (often well into a toddler's third year) plays a role. The purpose of this lengthy gap between pregnancies is the woman's health and convenience; it is best if she does not become pregnant again until her last child is old enough to walk when she is on the move, so that she does not have to carry an infant and a toddler at the same time.