Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2017;39(12):647-652
To determine cervical biometry in pregnant women between 18 and 24 weeks of gestation and the ideal mode of measurement of cervical length in cases of curved and straight cervical morphology.
The uterine cervices of 752 low-risk pregnant women were assessed using transvaginal ultrasound in a prospective cross-sectional study. In women with straight uterine cervices, cervical biometry was performed in a continuous manner. In women with curved uterine cervices, the biometry was performed using both the continuous and segmented techniques (in segments joining the cervical os). Polynomial regression models were created to assess the correlation between the cervical length and gestational age. The paired Student t-test was used to comparemeasuring techniques.
The cervical biometry results did not vary significantly with the gestational age and were best represented by linear regression (R2 = 0.0075 with the continuous technique, and R2 = 0.0017 with the segmented technique). Up to the 21st week of gestation, there was a predominance of curved uterine cervix morphology (58.9%), whereas the straight morphology predominated after this gestational age (54.2%). There was a significant difference between the continuous and the segmented measuring methods in all the assessed gestational ages (p < 0.001).
Cervical biometry in pregnant women between 18 and 24 weeks was represented by a linear regression, independently of the measuring mode. The ideal measuring technique was the transvaginal ultrasound performed at a gestational age 21 weeks.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2004;26(5):349-354
DOI 10.1590/S0100-72032004000500002
OBJECTIVE: to evaluate the accuracy of both the transverse diameter of the cerebellum (TDC) and of the transverse diameter/abdominal circumference (TDC/AC) ratio in the detection of fetal growth restriction (FGR), in high-risk pregnancies. METHOD: a prospective cross-sectional study was carried out in 260 patients with gestational age between 28 and 40 weeks. The TDC and AC of fetuses were measured through ultrasound and the fetuses with TDC below the 10th percentile or TDC/AC ratio above the 90th percentile (>14.6) were classified as FGR suspects. After birth, the accuracy of the TDC and TDC/AC was evaluated using the neonatal diagnosis of FGR as the gold standard (birth weight <10th percentile). RESULTS: after birth, 79 newborns (30.4%) were classified as small for gestational age. The TDC was appropriate in 74 (93.7%) of these fetuses and small in only 5 (6.3%). The sensitivity (SE), specificity (SP), positive (PPV) and negative (NPV) predictive values and accuracy of the TDC in the prediction of FGR were 6.3, 93.4, 29.4, 69.5, and 67%, respectively. The TDC/AC >14.6 correctly identified 59 of the 79 growth-restricted fetuses, with 27 false-positives and 20 false-negatives, SE of 74.5%, SP of 85.1%, PPV of 68.6%, NPV of 88.5% and 81.9% accuracy. CONCLUSION: the TDC is not a good screening parameter for the detection of FGR while the TDC/AC ratio above the 90th percentile is effective in this detection.