Hypertensive disorders of pregnancy in Greece.

Unique population data on the incidence of hypertension during pregnancy was obtained during the 1983 Greek National Perinatal Survey. Of the 9915 women delivering in April who had their blood pressures measured during pregnancy, only 3.0% had a diastolic pressure of over 90 mmHg. The data can be compared with 11.6% of 15,744 women delivering in the United Kingdom in one week of April 1970 and for whom data on antepartum blood pressures were available (p less than 0.0001). Corresponding rates for proteinuric pre-eclampsia were 0.7 and 3.1% (p less than 0.0001). In Greece, there was no consistent variation with parity but a strong trend with advancing maternal age. The perinatal mortality rate among pregnancies with diastolic pressures of 91 mmHg and more was 6%, three times the national rate. Such cross-cultural comparisons of hypertension in pregnancy form a valuable basis on which to develop hypotheses to explain the aetiology of this condition.