title: Primary and secondary infertility in sub-Saharan Africa.
abstract: BACKGROUND
  No previous study has provided national estimates of the prevalence of primary and secondary infertility in sizeable areas of sub-Saharan Africa.
  
  
  METHODS
  Primary infertility is measured by the proportion childless among women who entered their first marriage at least 7 years before date of censoring. Secondary infertility is measured by the 'subsequently infertile estimator' from parous ever-married women. Exposure begins at the age of the woman 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 years are used to determine her status as infertile or fertile at the last observation 5 years before censoring. A woman is considered infertile at last observation if she has had no livebirths during the last 5 years before censoring, otherwise she is considered fertile. A woman who has not given birth at age a or later is defined as being 'infertile subsequent to age a'. The index of the proportion subsequently infertile at age a is estimated as the number of women infertile subsequent to age a, divided by the total number 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 than a third of the 28 African countries analysed. In contrast, elevated levels of secondary infertility prevail in most countries. Secondary infertility for women age 20-44 ranges from 5% in Togo to 23% in Central African Republic.
  
  
  CONCLUSIONS
  It is feasible to gauge national levels of primary and secondary 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.
authors.affiliation: Department of Population and International Health, Harvard School of Public Health, Boston, MA 02115, USA. ularsen@hsph.harvard.edu
authors.forename: U
authors.initials: U
authors.lastname: Larsen
mesh_terms: D000293:Adolescent; D000328:Adult; D017954:Africa South of the Sahara / Q000453:epidemiology; D003267:Contraception / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D007247:Infertility, Female / Q000453:epidemiology* / Q000209:etiology; D008875:Middle Aged; D015995:Prevalence; D017584:Reproductive History; D012189:Retrospective Studies