The aim of this study was to retrospectively compare the perinatal mortality of Jewish and Bedouin hypertensive patients in the Southern area of Israel. Since almost 100% of the deliveries took place in the Soroka Medical Center, the sole hospital of the area, the computerized files of our department during 5 years (1986-1990) were used in the study. Data on the frequency of hypertensive disorder types, rates of stillbirths and neonatal deaths, maternal age and parity, pre-term and term deliveries, prenatal care, intrauterine growth retardation, mode of delivery and fetal sex, were analysed according to ethnicity. Among a total of 40,780 deliveries, 2343 were of hypertensive pregnancies. No difference in the prevalence of hypertensive disorders was found between Jewish and Bedouin women. Perinatal mortality in Jewish hypertensive women was 16.8/1,000 compared with 11.8/1,000 in normotensive, while among the Bedouins the rates were 44.4/1,000 and 22.9/1,000, respectively. In both populations half the rate of perinatal deaths were stillbirths, except among the Jewish hypertensive patients whose fetal deaths reached 72%. Of the risk factors examined the rate of inadequate prenatal care was higher among Bedouins than in Jews. Among women without prenatal care the Jewish hypertensives had a relative risk of 5.29 for perinatal mortality, compared to normotensive pregnant women, whereas in the Bedouins the relative risk was 2.54. Ethnicity was found not to have influence on the prevalence of hypertensive disorders among Jewish and Bedouin pregnant women.(ABSTRACT TRUNCATED AT 250 WORDS)