A substance in a pregnant woman’s urine may help doctors determine whether she’s likely to develop preeclampsia (search) later in her pregnancy, a new study suggests.

Preeclampsia is a common cause of high blood pressure during pregnancy, and also causes elevated levels of protein in the urine. Potential complications of preeclampsia include seizures, brain hemorrhage, uncontrolled bleeding, and kidney failure (search) as well as premature delivery. There is a greatly increased risk of death in babies delivered early.

The condition develops quickly and makes it hard for doctors to spot it in time before these dangerous complications develop.

But in a new study published in this week’s Journal of the American Medical Association, researchers found that reduced levels of a substance known as placental growth factor (PIGF) starting at weeks 25-28 of pregnancy were associated with a higher risk of developing preeclampsia later in the pregnancy.

If further studies confirm these results, researchers say screening for PIGF may offer a new way to predict preeclampsia risk and prevent complications.

Urine Substance Tied to Preeclampsia Risk

In the study, researchers studied urine concentrations of PIGF (search) in 120 pregnant women who later developed preeclampsia and 118 women with normal pregnancies.

They found that levels of PIGF were significantly lower beginning at 25 to 28 weeks of pregnancy among the women who subsequently developed preeclampsia than the other women. This difference between the two groups became more pronounced at 29 to 36 weeks.

In the women with normal pregnancies, the levels of PIGF were increased during the first two trimesters, peaked at 29 to 32 weeks of pregnancy, and then decreased.

In addition, among women with the lowest PIGF levels at 21 to 32 weeks of pregnancy, the risk of developing preeclampsia before 37 weeks, or during a pregnancy that produces a small size infant for its age, was markedly higher.

Researchers say if further studies confirm these results, screening women for PIGF may identify those who would most benefit from early diagnosis of preeclampsia and potentially help prevent preeclampsia-related complications.

By Jennifer Warner, reviewed by Brunilda Nazario, MD

SOURCE: Levine, R. The Journal of the American Medical Association, Jan. 5, 2005; vol 293: pp 77-85.