More than sixty years ago when biologists began to study the effects of DDT on laboratory animals, it was discovered that DDT interfered with reproductive development. Recent studies suggest DDT may inhibit the proper development of female reproductive organs that adversely affects reproduction into maturity. Additional studies suggest that a marked decrease in fertility in adult males may be due to DDT exposure. Most recently, it has been suggested that exposure to DDT in utero can increase a child's risk of childhood obesity. DDT is still used as anti-malarial insecticide in Africa and parts of Southeast Asia in limited quantities.