Urinary gonadotropin peptide levels in preeclamptic and normotensive pregnant women. Results from a pilot case-control study

Objective: Elevated maternal serum human chorionic gonadotropin (hCG) is an important marker of Down syndrome. Notably, women with unexplained elevated serum hCG in the second trimester experience a 2- to 5-fold increase risk of preeclampsia. Urinary gonadotropin peptide (UGP), thought to be a metabolite of hCG that is excreted into urine, has recently been shown to be elevated in Down syndrome pregnancies. We sought to examine urinary UGP levels in preeclamptic and normotensive pregnant women. Methods: We measured UGP levels in urine collected during the third trimester from 18 women with preeclampsia and 20 normotensive controls. UGP levels were determined using enzyme immunoassay and were corrected for dilution using urinary creatinine. Statistical significance testing was done using the Wilcox-on-Mann-Whitney Rank Sum test and Student t test statistics. Results: There was a statistically significant elevation in urinary UGP levels among preeclamptic cases as compared to normotensive control subjects (p = 0.013). Mean urinary UGP levels were 80.7 and 31.3 pmol/mg creatinine for preeclampsia cases and controls, respectively. Elevations in UGP levels among women with preeclampsia as compared with normotensive control subjects persisted after adjustments for possible confounding factors. Conclusion: These early findings suggest that elevations in urinary UGP may be a risk marker for preeclampsia. Prospective studies should further clarify the relation between urinary UGP levels and adverse pregnancy outcomes. These results are consistent with results suggesting a role of placental hypoperfusion in the etiology of preeclampsia.