Role of the glucose tolerance test as a predictor of preeclampsia.

OBJECTIVE: To determine whether oral glucose tolerance tests (OGTT) play a role as predictors of preeclampsia (PET) in pregnant women. METHODS: A retrospective case-control study was conducted in 2,002 singleton pregnancies that had a uterine artery (UtA) Doppler at 22-25 weeks and an OGTT. The UtA Doppler and OGTT were adjusted based on maternal characteristics, and the results were expressed as multiples of the expected normal median and compared between groups. Logistic regression analysis was used to determine whether maternal characteristics, OGTT, and UtA Doppler significantly contribute to the prediction of early- (<34 weeks), intermediate- (34-37 weeks), or late-onset (>37 weeks) PET. The performance of the screening was determined by ROC curves. RESULTS: Women who developed PET were characterized by an older maternal age, an increased body mass index, and an altered UtA Doppler. The group with intermediate-onset PET was the only one associated with higher 2-hour OGTT levels compared to controls. Combined models were developed via logistic regression analysis using maternal characteristics, UtA Doppler, and OGTT to predict PET. These combined models were able to detect around 74, 42, and 21% of women who later developed early-, intermediate-, or late-onset PET, respectively, with only a 5% false-positive rate. CONCLUSIONS: This study shows that the combination of maternal characteristics, second-trimester UtA Doppler, and OGTT is a predictor of the development of PET in healthy pregnant women.

Screening for trisomy 21 during the routine second-trimester ultrasound examination in an unselected Chilean population.

OBJECTIVE: To evaluate the performance of a detailed ultrasound examination during the second trimester as a screening test for Down syndrome in an unselected Chilean population. METHODS: This was part of an ongoing longitudinal study. Included were 3071 women with singleton pregnancies who underwent routine ultrasound examination between 21 + 0 and 25 + 6 gestational weeks as a screening test for chromosomal abnormalities and major congenital structural defects, and who were diagnosed as having trisomy 21 or being chromosomally normal. Maternal age, and eight soft markers and cardiac defects associated with Down syndrome were evaluated as a screening test using logistic regression analysis. RESULTS: The incidence of Down syndrome was 0.6%, and the mean maternal age was 29.4 +/- 6.2 years. At least one of four soft markers (absent nasal bone, nuchal edema, short femur, echogenic foci) and/or cardiac defects was present in 77.8% of Down syndrome fetuses and in 3.1% of normal fetuses. Furthermore, with a false-positive rate of 1%, the detection rate using the combined model of ultrasound markers and maternal age was 72.2%. CONCLUSIONS: Second-trimester ultrasound markers are able to detect over 70% of Down syndrome fetuses with only a 1% false-positive rate.