The recorded incidences of adolescent pregnancy and adolescent
birth are widely divergent. For most countries, comparable figures
are available on birth rates to mothers aged between fifteen and
nineteen. Table 2.1 is based on UNICEF (1998) figures cited in a
recent WHO report on adolescent pregnancy (WHO, 2006). These
figures are based on birth registration rates and in most developed
countries these figures are reliable. However, in some of the
developing countries the data can only be based on best estimates
available .