Brief Answer:
Not always fatal. The incidence was always same.

Detailed Answer:
Hello Dear XXXXXXX

Thanks for your question.

Preeclampsia is a condition in pregnancy that is diagnosed when a pregnant lady has these three signs or findings, High Blood pressure, protein in the urine, and edema (swelling of the feet due to fluid retention). Edema and proteinuria are not mandatory.

The problem is basically due to high blood pressure and prompt treatment of high blood pressure during pregnancy will reduce the chances of a lady progressing into preeclampsia-eclampsia.

Preeclapmsia is a preceding state of eclampsia, eclampsia is when a pregnant lady develops seizures due to uncontrolled high blood pressure, so the doctors are always are on the look out for pregnant women who have higher blood pressures.

As with all medical advances, the incidence of eclampsia is down after the advent of good and safe blood pressure medicines, but the incidence of PIH (pregnancy induced hypertension) is the same, consequently, due to better medical research we have succeeded in preventing many women with PIH from progressing to preeclampsia or eclampsia, but the problem is a major cause of maternal mortality in developing countries with poor health systems.

I can say, preeclampsia would be more commonly seen before 1950s.

I hope this information is sufficient for you, you can write back to me if you need more information or if you need to discuss further.

Warm regards.

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