Unmet need
Definition
The term unmet need refers to a situation where females are able to become pregnant and sexually active but are not using any method of contraception (modern or traditional), and report wanting to delay the next child or limit their number of births.
Unmet need is a potential explanation for a gap between desired fertility and expected fertility with desired fertility being higher than expected fertility (and also higher than completed fertility), i.e., females expect to end up having more children than they want. Unmet need might also lead to birth spacing that differs from what the female wants. It is also possible that the latter effect exists in isolation, without the former.