Risk factors for developing preeclampsia during pregnancy include:

• Chronic (ongoing) high blood pressure (hypertension). Women with chronic high blood pressure have a nearly 1-in-4 chance of developing preeclampsia. The risk is greatest when high blood pressure has been present for at least 4 years, is caused by poor kidney function, and was present during a previous pregnancy.⁹
• Chronic kidney disease.
• Disease of the blood vessels (vascular disease).
• Diabetes.
• High blood pressure in a past pregnancy, especially before week 34.
• Personal history of preeclampsia.
• Family history of preeclampsia, especially if either you or your partner were born from a pregnancy affected by preeclampsia.⁴
• Obesity (more than 20% over ideal weight) at the time of conception. If your weight is within this range, the higher your prepregnancy body mass index, the greater your preeclampsia risk.¹³
• Multiple pregnancy (such as twins or triplets).
• First pregnancy ever, first-time pregnancy with current partner, or first pregnancy in the past 10 years.^{3, 14}
• Age younger than 21 or older than 35.
• Molar pregnancy.
• Fetal hydrops, which is caused by Rh sensitization or an infection in the uterus.
• Pregnancy from in vitro fertilization using donor eggs.¹⁵

Women with chronic high blood pressure have an increased risk of the premature separation of the placenta from the uterine wall (placenta abruptio). This risk is further increased when:

• A mother smokes during pregnancy. Smoking is considered a cause of 15% to 25% of all placental abruption episodes.¹⁶
• Preeclampsia develops in addition to chronic high blood pressure.⁹

Preeclampsia probably does not cause future high blood pressure. Instead, experts think that some women who have preeclampsia also have a higher-than-normal risk of chronic high blood pressure after pregnancy or later in life.¹