Prediction of progression to a high risk situation in women with gestational hypertension or mild pre-eclampsia at term

Objective: To evaluate whether progression to a high-risk situation is predictable in women with gestational hypertension (GH) or mild pre-eclampsia (PE) at term. Methods: Women with a singleton pregnancy, a fetus in cephalic position, between 36 and 41 weeks of gestation, complicated by GH or mild PE that were managed expectantly, were selected from the HYPITAT trial. We evaluated the predictability of progression to a high-risk situation. Logistic regression was used to determine the predictive value of clinical characteristics or laboratory findings and to generate a prediction model for progression to a high-risk situation. The predictive value of this model was assessed with receiver-operating characteristic (ROC) analysis, calibration and internal validation. Results: We included 703 women, of whom 244 (34.7%) had progression to a high-risk situation. After multivariable analysis, nulliparity (OR 1.87), maternal age (OR 1.05 per year), gestational age (OR 0.88 per week), previous abortion (OR 1.26), ethnicity (OR 2.05 for non-Caucasian ethnicity), diastolic (OR 1.04 per mmHg), systolic blood pressure (OR 1.02 per mmHg) and the laboratory parameters proteinuria, haemoglobin, platelets, uric acid and alanine aminotransferase were included in the final model. The area under the ROC curve of this model was 0.71 (95% CI, 0.67-0.74). Even though the goodness of fit was moderate (P = 0.40), internal validation showed the model could hold in the overall population. Conclusion: In the prediction of progression to a high-risk situation, in women with GH or mild PE at term, a distinction can be made between women with a low risk and women with high risk.