Background No previous study has provided national estimates of the prevale
nce of primary and secondary infertility in sizeable areas of sub-Saharan A
frica.
Methods Primary infertility is measured by the proportion childless among w
omen who entered their first marriage at least 7 years before date of censo
ring. Secondary infertility is measured by the 'subsequently infertile esti
mator' from parous ever-married women. Exposure begins at the age of the wo
man at the birth of her first child, and exposure ends when the woman is of
an age, which is 5 years lower than her age at censoring. These last 5 yea
rs are used to determine her status as infertile or fertile at the last obs
ervation 5 years before censoring. A woman is considered infertile at last
observation if she has had no livebirths during the last 5 years before cen
soring, otherwise she is considered fertile. A woman who has not given birt
h at age a or later is defined as being 'infertile subsequent to age a'. Th
e index of the proportion subsequently infertile at age a is estimated as t
he number of women infertile subsequent to age a, divided by the total numb
er of women observed at that age. Infertility is estimated for women age 20
-44.
Results Primary infertility is relatively low and it exceeds 3% in less tha
n a third of the 28 African countries analysed. In contrast, elevated level
s of secondary infertility prevail in most countries. Secondary infertility
for women age 20-44 ranges from 5% in Togo to 23% in Central African Repub
lic.
Conclusions It is feasible to gauge national levels of primary and secondar
y infertility from population based surveys including a birth history. The
prevalence of infertility of pathological origin is so high in sub-Saharan
Africa that infertility is not merely an individual concern, it is a public
health problem.