The pygmy slow loris mates once every 12–18 months and has one or two offspring after an average gestation period of six months. For the first few days, the young loris clings to the belly of its mother. The offspring will be nursed for an average of 4.5 months, but weaning can sometimes take up to 8 months. The females reach sexual maturity at about 9 months, while the male reaches maturity by about 18-20 months. The pygmy slow loris is seasonally fertile during the months of July and October. Chemical signals play a role in the reproductive behavior of female pygmy slow lorises. Urine scent markings have a strong characteristic odor and are used to communication information about social relationships.