Prevalence of pregnancy hypertensive disorders in Mongolia.

Objective: To estimate the prevalence of preeclampsia in a contemporary population of Mongolian women living in urban and rural areas. We determined the sensitivity and specificity of diagnosis based on established diagnostic criteria and assessed whether local diagnostic criteria were similar to those used in the US.

Study Design: Cross-sectional study of urban and nomadic pregnant women recruited in Ulaanbaatar (n=136) and rural provinces (n=85).

Main Outcome Measures: Preeclampsia defined as hypertension new to pregnancy after 20weeks and proteinuria (or protein creatinine ratio ⩾0.3 and dipstick reading>+1) or in the absence of proteinuria, hypertension and onset of: renal insufficiency, impaired liver function, thrombocytopenia, pulmonary edema, cerebral/visual symptoms. Prevalence of preeclampsia based on established criteria was compared with prevalence based on local physician's diagnosis.

Results: Prevalence of local physician diagnosed preeclampsia was 9.5% (13.2% urban, 3.5% rural). Prevalence based on established diagnostic criteria was 4.1% (4.4% urban, 3.5% rural). Sensitivity of physician's diagnosis was 23.8%, specificity was 98.0%, false negative rate was 2.0% and false positive rate was 76.2%. While prevalence based on local physician's diagnosis was over double that based on diagnostic criteria, overdiagnosis did not result in adverse effects. Women fulfilling diagnostic criteria for preeclampsia had babies with higher birth weights than women who did not (p-value=0.006).

Conclusion: The 4.1% prevalence of preeclampsia in Mongolia was consistent with global estimates of 2-8%, suggesting the pathophysiology of preeclampsia here may be similar to that found globally. Sensitivity of physician's diagnosis was low, specificity was high.