Answers are grounded in this paper and cite their sources.
In the years 1969 - 1973, 0.3% of 17000 unselected non-diabetic pregnancies were complicated by severe pre-eclampsia, 0.6% by mild pre-eclampsia and 0.6% by hypertension in pregnancy. Records from affiliated maternity centers and the hospital were studied for these 261 women and for 260 women with matched normotensive pregnancies. The women with pre-eclampsia/hypertension in pregnancy had higher blood pressure than the control group very early in pregnancy. The hypertensive women were more often primiparous and they had a slightly higher body weight. The patients with severe pre-eclampsia were older than the other women (30.4 vs 25.4 years for controls, p less than 0.001). Immigrants were not more commonly found in the hypertensive groups, but unmarried mothers were more often seen in the mild pre-eclampsia and pregnancy hypertension groups, 19.1% and 20.6% respectively compared to 7.7% in the control group (p less than 0.01). A family history of hypertension was frequently reported in all groups. The most striking characteristic of women with pre-eclampsia/hypertension in pregnancy was their elevated blood pressure before or very early in pregnancy.
No takes yet. Share an insight, caveat, or question.
Svensson et al. (1985) studied this question.
Synapse has enriched 5 related papers. Consider them for comparative context: