Trends of sex ratios in an urban Saudi Arabian population

Objectives: This study analyzes the distribution of sex ratio at birth in a Saudi population using data collected from the birth database of an urban teaching hospital and to assess the potential effect of the gulf war on it.
Design: Database on all hospital births was used to calculate the sex ratios for all live births.
Setting: Births at King Khalid University Hospital (KKUH), Riyadh, Saudi Arabia totaling 67,643.
Subjects: All live births from 1983 -2000.
Outcome Measure: Sex ratio male/female (expressed as the proportion of the total live births that were males).
Results: The average sex ratio from 67,643 births, was 1.033 (95% CI, 1.029-1.037), significantly different from the world average of 1.055. The male proportion at King Khalid University Hospital, Riyadh, decreased significantly after 1990 (Gulf war). This represented a cumulative loss of 15.7 male births per 1000 live births from 1983-2000.
Conclusion: The decreased sex ratio observed in our study as well as in other parts of the world add to the importance of the effect of environmental factors on the reproductive health of populations, in addition to the sensitivity of the sex ratio as an unambiguous marker for that.