Background: The results of various studies have suggested a link between reduced fertility rate and improvements in women's health, particularly in the developing world. Despite the substantial reductions in Arab countries, the fertility rate in the occupied Palestinian territory (oPt) remains one of the highest in the world. Because of the increased education of Palestinian women, high rates of urbanisation, low rate of infant mortality, and improved access to contraception compared with other countries in the region with lower fertility rates, the persistently high fertility rate in the oPt has been described as a demographic puzzle. The proximate determinants of the high fertility rate in the oPt were analysed. These were based on Bongaarts framework and are the biological mechanisms, including marriage, contraception, post-partum amenorrhoea (as a result of breastfeeding duration), and induced abortion, that affect fertility.

Methods: Bongaarts framework was used to do a decomposition analysis of the proximate determinants of the trends in fertility rates in the oPt between 1996 and 2006. Data for the analysis were obtained from the 1996 health survey, 2000 Demographic Health Survey, and 2006 Palestinian Family Health Survey. Separate indices for the contributions of marriage, contraception, and post-partum infecundability were calculated (index for abortion was not calculated for abortion because data were not available). The index of proportion of married women is based on the weighted average age of the age-specific proportions of married women, weighted according to the age-specific fertility rates for women. The index of contraception is based on the proportion of women using contraception and the effectiveness of the type of contraception used. The index of post-partum infecundability is based on the duration of post-partum amenorrhoea and breastfeeding. Access to the data set was granted by the Palestinian Central Bureau of Statistics.

Findings: Between 1996 and 2006, contraceptive use accounted for the greatest fall in fertility; 16·8% in the West Bank and 14·7% in the Gaza Strip. In the West Bank, post-partum infecundability accounted for a reduction in fertility of 5·4% compared with 3·6% in the Gaza Strip, mainly because of increased duration of breastfeeding. Changes in the patterns of marriage—fewer marriages in the younger age groups 15–19 years and 20–24 years—led to a reduction in fertility of 6·7% in the Gaza Strip compared with 1·9% in the West Bank. Overall, most of the fall in fertility took place between 2000 and 2006 in the West Bank, whereas the reduction was fairly even between 1996 and 2006 in the Gaza Strip.