The law requires government health centres to hand out free condoms and birth control pills, benefiting tens of millions of the country’s poor who would not otherwise be able to afford or have access to them.
It also mandates that sex education be taught in schools and public health workers receive family planning training, while post-abortion medical care has been made legal for the first time.
Proponents say the law will slow the country’s rapid population growth, cut widespread poverty and reduce the number of mothers dying at child birth.
“This is a triumph for poor women and girls who would otherwise have no access to these things,” the United Nations Population Fund’s country representative, Ugochi Daniels, told AFP.