Moreover, despite the obvious role of contraception as a proximate determinant of fertility, the additional effect of contraceptive availability or family planning on fertility is quantitatively small and explains very little cross country variation.
In Kenya, for example, as a result of diminished financial support for family planning and increasing fertility, the country's projected population in 2050 is set to reach 83m, from 54m.
And in Iran, public policy and investment in family-planning services made the difference between rising fertility between 1979 and 1984 and falling fertility thereafter, not the rise in national incomes, nor female education.