Population screening for gestational hypertensive disorders using maternal, fetal and placental characteristics: A population-based prospective cohort study

Abstract

Objective: To determine screening performance of maternal, fetal and placental characteristics for selecting pregnancies at risk of gestational hypertension and preeclampsia in a low-risk multi-ethnic population.

Method: In a prospective population-based cohort among 7124 pregnant women, we collected maternal characteristics including body mass index, ethnicity, parity, smoking and blood pressure in early-pregnancy. Fetal characteristics included second and third trimester estimated fetal weight and sex determined by ultrasound. Placental characteristics included first and second trimester placental growth factor concentrations and second and third trimester uterine artery resistance indices.

Results: Maternal characteristics provided the best screening result for gestational hypertension (area-under-the-curve [AUC] 0.79 [95% Confidence interval {CI} 0.76-0.81]) with 40% sensitivity at 90% specificity. For preeclampsia, the maternal characteristics model led to a screening performance of AUC 0.74 (95% CI 0.70-0.78) with 33% sensitivity at 90% specificity. Addition of second and third trimester placental ultrasound characteristics only improved screening performance for preeclampsia (AUC 0.78 [95% CI 0.75-0.82], with 48% sensitivity at 90% specificity).

Conclusion: Routinely measured maternal characteristics, known at the start of pregnancy, can be used in screening for pregnancies at risk of gestational hypertension or preeclampsia within a low-risk multi-ethnic population. Addition of combined second and third trimester placental ultrasound characteristics only improved screening for preeclampsia.

FIGURE 1

Screening performance for gestational hypertension based on maternal, fetal and placental characteristics. AUC, area under the curve; CI, confidence interval; EFW, estimated fetal weight; PlGF, placental growth factor; UtA‐RI, uterine artery resistance index. Values are AUC (95% CI), Sensitivity at 70%, 80% and 90% specificity. ^†Maternal characteristics model: maternal age, BMI, ethnicity, parity and smoking; Blood pressure model: Maternal characteristics model and first trimester mean arterial pressure per 10 mmHg. ^‡Baseline model: maternal age, BMI, ethnicity, parity and smoking, and first trimester MAP per 10 mmHg; Fetal sex model: Baseline model + fetal sex; second trimester EFW model: Baseline model and second trimester estimated fetal weight <10th percentile; third trimester EFW model: Baseline model and third trimester estimated fetal weight <10th percentile; second and third trimester EFW model: Baseline model, second and third trimester estimated fetal weight <10th percentile. ^§Baseline model: maternal age, BMI, ethnicity, parity, smoking, and first trimester MAP per 10 mmHg; second trimester UtA‐RI model: Baseline model, second trimester uterine artery resistance index >90th percentile; third trimester UtA‐RI model: Baseline model, third trimester uterine artery resistance index >90th percentile; second and third trimester UtA‐RI model: Baseline model, second and third trimester uterine artery resistance index >90th percentile. First trimester PlGF model: Baseline model, first trimester placental growth factor <10th percentile; second trimester PlGF model: Baseline model, second trimester placental growth factor <10th percentile; first and second trimester PlGF model: Baseline model, first and second trimester placental growth factor <10th percentile

FIGURE 2

Screening performance for preeclampsia based on maternal, fetal and placental characteristics. CI, confidence interval; EFW, estimated fetal weight; PlGF, placental growth factor; UC, area under the curve; UtA‐RI, uterine artery resistance index. Values are AUC (95% CI), Sensitivity at 70%, 80% and 90% specificity. ^†Maternal characteristics model: maternal age, BMI, ethnicity, parity and smoking; Blood pressure model: Maternal characteristics model and first trimester mean arterial pressure per 10 mmHg.^‡Baseline model: maternal age, BMI, ethnicity, parity and smoking, and first trimester MAP per 10 mmHg; Fetal sex model: Baseline model + fetal sex; second trimester EFW model: Baseline model and second trimester estimated fetal weight <10th percentile; third trimester EFW model: Baseline model and third trimester estimated fetal weight <10th percentile; second and third trimester EFW model: Baseline model, second and third trimester estimated fetal weight <10th percentile.^§Baseline model: maternal age, BMI, ethnicity, parity, smoking, and first trimester MAP per 10 mmHg; second trimester UtA‐RI model: Baseline model, second trimester uterine artery resistance index >90th percentile; third trimester UtA‐RI model: Baseline model, third trimester uterine artery resistance index >90th percentile; second and third trimester UtA‐RI model: Baseline model, second and third trimester uterine artery resistance index >90th percentile. Second and third trimester UtA‐RI model and first trimester PlGF model: second and third trimester UtA‐RI model, first trimester placental growth factor < 10th percentile; second and third trimester UtA‐RI model and second trimester PlGF model: second and third trimester UtA‐RI model, second trimester placental growth factor <10th percentile; second and third trimester UtA‐RI model and first and second trimester PlGF model: second and third trimester UtA‐RI model, first and second trimester placental growth factor < 10th percentile

FIGURE 3

Screening performance for secondary outcome early‐onset preeclampsia based on maternal, fetal and placental characteristics. AUC, area under the curve; CI, confidence interval; EFW, estimated fetal weight; PlGF, placental growth factor; UtA‐RI, uterine artery resistance index. Values are AUC (95% CI), Sensitivity at 70%, 80% and 90% specificity. ^†Maternal characteristics model: maternal age, BMI, ethnicity, parity and smoking; Blood pressure model: Maternal characteristics model and first trimester mean arterial pressure per 10 mmHg. ^‡Baseline model: maternal age, BMI, ethnicity, parity and smoking, and first trimester MAP per 10 mmHg; Fetal sex model: Baseline model + fetal sex; second trimester EFW model: Baseline model and second trimester estimated fetal weight <10th percentile; third trimester EFW model: Baseline model and third trimester estimated fetal weight <10th percentile; second and third trimester EFW model: Baseline model, second and third trimester estimated fetal weight <10th percentile.^§Baseline model: maternal age, BMI, ethnicity, parity, smoking, and first trimester MAP per 10 mmHg, and third trimester EFW; second trimester UtA‐RI model: Baseline model, second trimester uterine artery resistance index >90th percentile; third trimester UtA‐RI model: Baseline model, third trimester uterine artery resistance index >90th percentile; second and third trimester UtA‐RI model: Baseline model, second and third trimester uterine artery resistance index >90th percentile. First trimester PlGF model: Baseline model, first trimester placental growth factor <10th percentile; second trimester PlGF model: Baseline model, second trimester placental growth factor <10th percentile; first and second trimester PlGF model: Baseline model, first and second trimester placental growth factor <10th percentile