Preeclampsia is a life-threatening medical condition that can happen in about 10% of women usually during the second half of pregnancy and postpartum postbirth. The major signs of preeclampsia are high blood pressure and protein in the urine. Women with preeclampsia can develop headaches and seizures, at which point preeclampsia becomes eclampsia. Both preeclampsia and eclampsia can threaten the baby's and mother's life and potentially injure many organs such as the brain, heart, kidneys, and liver. We don't completely understand yet why it happens, and the treatment is usually to deliver the baby. Most women get well as soon as the baby is born.

Risk Factors:

Pregnancy-associated factors

  • Multiple gestations (twins, triplets,..) 
  • Having a baby with chromosomal abnormalities
  • Hydatidiform mole
  • Hydrops fetalis
  • Oocyte donation or donor insemination
  • Structural congenital anomalies
  • Urinary tract infection 

 Maternal-specific factors

  • Younger and older mothers (less than 20 years  or greater than 35 years)
  • Hypertension - before pregnancy
  • African-American decent
  • Obesity
  • A family history of preeclampsia (Mother or sister)
  • Nulliparity  (First baby)
  • Preeclampsia in a previous pregnancy
  • Women with certain medical conditions: gestational diabetes, type I diabetes, lupus, renal disease, thrombophilias
  • Stress
  • New partner

Paternal-specific factors

  • First-time father
  • Previously fathered a preeclamptic pregnancy with another woman

Family history of preeclampsia

Last week I saw a patient for her first prenatal visit. She was 8 weeks pregnant and her pregnancy was achieved through IVF (in-vitro fertilization). There wasn't much in her medical history — she was healthy and had not had any medical issues. When I inquired about her family, however, she said that her sister had delivered a son at 28 weeks after she developed severe preeclampsia and seizures (eclampsia).

We then sat down and discussed her sister's preeclampsia and the possible implications on her own pregnancy. She was surprised to hear that this would increase her risk of developing preeclampsia too. She said that even though she had been seen her regular Ob-Gyn for some time he never mentioned that her sister's eclampsia may indicate that she herself may be at risk. 

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Family history of preeclampsia study

In October 2005 the British Medical Journal published a study called "Recurrence of pre-eclampsia across generations: exploring fetal and maternal genetic components in a population-based cohort." The study found the following:

  • The daughters of women who had pre-eclampsia during pregnancy had more than twice the risk of pre-eclampsia themselves (odds ratio 2.2, 95% confidence interval 2.0 to 2.4) compared with other women.
  • Men born after a pregnancy complicated by pre-eclampsia had a moderately increased risk of fathering a pre-eclamptic pregnancy (1.5, 1.3 to 1.7).
  • Sisters of affected men or women, who were themselves born after pregnancies not complicated by pre-eclampsia, also had an increased risk (2.0, 1.7 to 2.3).
  • Women and men born after pre-eclamptic pregnancies were more likely to trigger severe pre-eclampsia in their own (or their partner's) pregnancy (3.0, 2.4 to 3.7, for mothers and 1.9, 1.4 to 2.5, for fathers).

The authors concluded that maternal genes and fetal genes from either the mother or father may trigger preeclampsia. The maternal association is stronger than the fetal association and the familial association predicts more severe preeclampsia.

The bottom line is that when assessing certain risks you should not overlook your family's medical history. Discuss it with your doctor even if your doctor doesn't ask you about it.

History of prior preeclampsia

A woman who had preeclampsia in a previous pregnancy has an increased risk of recurring preeclampsia in her next pregnancy. The exact recurrence risk depends on several factors that are related both to the mother's medical condition, when it was diagnosed, and the circumstances of her prior preeclampsia. The risk of recurrence increases if preeclampsia in the previous pregnancy was diagnosed early into the pregnancy and if the woman has had preeclampsia in two previous pregnancies. Women with chronic hypertension, for example, have a 70% risk of recurring preeclampsia in the next pregnancy. And women with severe preeclampsia in their first pregnancy have a 45% risk of recurrence.

Diet and preeclampsia

A recent study found the presence of ergothioneine, an antioxidant found in fungi, in the blood of women with preeclampsia to be higher than healthy pregnant women. The fungi can be ingested when pregnant women consume unpasteurized dairy products.

Preeclampsia affects 10% of the pregnant population. The condition, which has no known cause, can result in dangerously high blood pressure and fetal death. The only cure for preeclampsia is delivery of the baby. Scientists hope the detection of ergothioneine levels will lead to early detection of preeclampsia and understanding of the cause for the condition.

While doctors are not telling pregnant women to stop eating unpasteurized dairy products, they understand that further study is needed into why ergothioneine levels are higher in women with preeclampsia. "Ergothioneine is known as an antioxidant and antioxidants have been proposed to be helpful in reducing the risk of preeclampsia. It is therefore very interesting that we have found it to be in excess for women with the condition," says Dr. Fisher.

The research team used an MRI like a scan of blood cells to determine the presence of chemicals in the blood. Chemical markers for preeclampsia have also been found in blood plasma in previous studies.

Source: Reproductive Sciences 2009

Migraines and preeclampsia

More rigorous epidemiologic and laboratory studies are needed to clarify the relationship between migraines and preeclampsia given the high prevalence of migraines in reproductive-age women, that 8 of 10 studies have indicated an association between migraines and pregnancy-induced hypertension (or preeclampsia), and that available evidence suggests that women with either condition are at increased risk of stroke. A true association between migraines and preeclampsia may yield further clues into the mysterious causes of both disorders.

If certain women are predisposed to endothelial headache dysfunction and ischemia (placental or cerebral), they may be at elevated risk for stroke and severe cerebral damage.

Early diagnosis and treatment of migraine may help prevent adverse pregnancy outcomes and future occurrence of serious vascular disorders.

More preeclampsia information