Search

Objective: The purpose of this study was to assess the fetal outcome of first-trimester pregnancies with reversed end-diastolic flow in the umbilical artery. Study Design: Doppler studies in the umbilical artery were carried out in 2970 consecutive pregnancies scanned at 10 to 14 weeks. Results: We observed 11 (0.4%) cases of reversed end-diastolic flow. Of these, an autosomal trisomy was shown in 7 and a congenital heart defect in 2 additional fetuses. Fetal demise was observed in 5 pregnancies, neonatal death was observed in 1, and termination of pregnancy was carried out in 4. Only 1 fetus survived. Conclusions: Reversed end-diastolic flow in first-trimester umbilical artery signals an ominous prognosis even with normal karyotype. (Am J Obstet Gynecol 2001;185:204-7.)

Objective: Our purpose was to assess the ductus venosus blood flow in trisomy 21 fetuses in the first half of pregnancy and the relation of this blood flow to nuchal thickness. Study Design: The ductus venosus blood flow has been studied in 534 consecutive fetuses between 10 and 18 weeks of gestation who were undergoing prenatal invasive diagnostic procedures. Before the sampling, the velocity during atrial contraction, the pulsatility index for veins, and the ratio of systole–end-systole to diastole were established in the Doppler waveforms and eventually correlated with the fetal karyotype. Results: Ductus venosus waveforms were successfully obtained in 82% of the pregnancies. Eleven fetuses were found to have trisomy 21; the pulsatility index was abnormally increased (>95th percentile) in 73% (8/11), the ratio of systole–end-systole to diastole was abnormally increased in 45% (5/11), and the velocity during atrial contraction was decreased ( Conclusions: An abnormally increased ductus venosus pulsatility index was found in a substantial proportion of early trisomy 21 fetuses, and this was apparently independent of nuchal thickening. (Am J Obstet Gynecol 1998;179:1612-7.)

OBJECTIVES: We sought to evaluate the circulating levels of lipid peroxides and vitamin E and the placental levels of lipid peroxides in pregnant women with different types of hypertension. STUDY DESIGN: Lipid peroxides were measured in serum and placental tissue by the thiobarbituric acid method and high-pressure liquid chromatography, and vitamin E was measured by high-pressure liquid chromatography. The patients studied were 36 healthy pregnant women and 92 women with hypertension classified as having mild gestational hypertension ( n = 28), severe gestational hypertension ( n = 10), preeclampsia ( n = 34), and chronic hypertension ( n = 20). RESULTS: Lipid peroxides in serum and placental tissue were significantly increased, and vitamin E levels in serum were significantly decreased in women with severe gestational hypertension and preeclampsia compared with controls. The groups of mild gestational hypertension or chronic hypertension had similar values of lipid peroxides or vitamin E as controls. CONCLUSIONS: Our results suggest that the category of gestational hypertension may be composed of at least two entities with different pathophysiology and support the concept of nonproteinuric preeclampsia. (Am J Obstet Gynecol 1998;178:1072-6.)

OBJECTIVE: Our purpose was to assess the validity of nuchal thickness in the prediction of Down syndrome in early midtrimester fetuses. STUDY DESIGN: In 1543 consecutive pregnancies undergoing amniocentesis, primarily for advanced maternal age, nuchal thickness was prospectively measured between 13 and 18 weeks and then correlated with the karyotype obtained from amniotic fluid. RESULTS: With the cutoff value suggested in the literature ( ≥ 6 mm), 33.3% (6/18) of the cases of Down syndrome would be detected for a 0.1% (2/1424) false-positive rate, with a positive predictive value adjusted to a prevalence of Down syndrome in the general population of 1:3. To increase the sensitivity of the method, the threshold was lowered to 5 mm, achieving a sensitivity of 77.8% (14/18) for a 2.1% (30/1424) false-positive rate and an adjusted positive predictive value of 1:19. CONCLUSIONS: In early midtrimester fetuses decreasing the nuchal thickness threshold to 5 mm substantially enhances the detection of Down syndrome with a reasonable false-positive rate. (Am J Obstet Gynecol 1996;175:45-9.)