Human Reproduction vol.13 no.5 pp.1394–1396, 1998 Trends in male:female ratio among newborn infants in 29 countries from five continents

6To whom all correspondence should be addressed We have analysed trends in male:female ratios among newborns between 1950 and 1990 in 29 countries from five continents. The numbers of liveborn males and females over the period 1950–1994 were derived from the World Health Organization (WHO) database. Countries for which reliable data were available included 20 major European countries (excluding the former Soviet Union, Albania and a few small countries), Canada, the USA, selected countrie