Ultrasound assessment of premenopausal bleeding.

Vaginal bleeding is the most common cause of emergency care in the first trimester of pregnancy and accounts for the majority of premenopausal bleeding cases. Ultrasound evaluation combined with a quantitative beta human chorionic gonadotropin test is an established diagnostic tool to assess these patients. Spontaneous abortion because of genetic abnormalities is the most common cause of vaginal bleeding; ectopic pregnancy and gestational trophoblastic disease are other important causes and in all patients presenting with first trimester bleeding, ectopic pregnancy should be suspected and excluded, as it is associated with significant maternal morbidity and mortality. A thorough knowledge of the normal sonographic appearance of intrauterine gestation is essential to understand the manifestations of an abnormal gestation. Arteriovenous malformation of the uterus is a rare but important cause of vaginal bleeding in the first trimester, as it has to be differentiated from the more common retained products of conception, with which it is often mistaken.

Assessment of yolk sac volume by 3D-sonography using the XI VOCAL method from 7 to 10 + 6 weeks of pregnancy.

PURPOSE: To access the yolk sac (YS) volume between 7 and 10 + 6 gestational weeks of pregnancy by threedimensional (3D) ultrasonography using extended imaging virtual organ computer-aided analysis (XI VOCAL) method. METHODS: For this cross-sectional study, 64 pregnant patients between 7 and 10 + 6 gestational weeks were enrolled and normal pregnancies were included. The XI VOCAL 10 slices manual method was used for the YS volumetry by 3D ultrasonography. The statistical analysis first obtained the means, medians, standard deviation, and maximum and minimum volume values. The correlation of YS volume to the gestational age (GA) and the crown-rump length (CRL) was evaluated by models of polynomial regression, being adjusted by determination coefficient (R (2)). RESULTS: The mean YS estimated volume ranged from 0.06 ± 0.03 cm(3) [0.02-0.11 cm(3)] to 0.16 ± 0.12 cm(3) [0.01-0.38 cm(3)] and showed to be weakly correlated to the GA [YS volume = exp(0.261 × GA + 0.008); R (2) = 0.14] and the CRL [YS volume = exp(0.033 × CRL + 0.035); R (2) = 0.13]. CONCLUSIONS: The YS volume estimated by 3D ultrasonography using the method XI VOCAL correlated weakly with GA and CRL in normal singleton pregnancies between 7 and 10 + 6 gestational weeks.

Functional linear discriminant analysis: a new longitudinal approach to the assessment of embryonic growth.

BACKGROUND: Functional linear discriminant analysis (FLDA) is a new growth assessment technique using serial measurements to discriminate between normal and abnormal fetal growth. We used FLDA to assess and compare growth in live pregnancies destined to miscarry with those remaining viable. METHODS: This was a prospective cohort study of women with ultrasound scans on at least two separate occasions showing live pregnancies. Serial crown-rump length (CRL), mean gestational sac diameter and mean yolk sac diameter measurements were recorded. The ability of FLDA to predict subsequent miscarriage was compared with that of a single CRL measurement. RESULTS: Of 521 included pregnancies, 493 (94.6%) remained viable at 14 weeks and 28 (5.4%) miscarried. The CRL growth rate was significantly lower in those that miscarried (one-sample t-test, P = 2.638E-22). The sensitivity of FLDA in predicting miscarriage from serial CRL measurements was 60.7% and specificity was 93.1% [positive predictive value (PPV) 33.3%, negative predictive value (NPV) 97.7%]. This was significantly better for predicting miscarriage than a single CRL observation of more than 2SD below that expected (sensitivity 53.6%, specificity 72.2%, PPV 9.9%, NPV 96.5%). CONCLUSIONS: FLDA discriminates between normal and abnormal growth to predict miscarriage with high specificity. FLDA predicts miscarriage better than a single observation of a small CRL.

Parallel Doppler assessment of yolk sac and intervillous circulation in normal pregnancy and missed abortion.

This study assessed yolk sac morphology and vascularity and intervillous blood flow in normal early pregnancy and missed abortion. Transvaginal colour and pulsed Doppler were used in a prospective analysis of 87 normal pregnancies and 48 missed abortions between 6 and 12 weeks gestation. The Kruskal-Wallis rank test was used to calculate the difference in yolk sac diameter and vascularity visualization rate between gestational weeks. Repeated measures analysis of variance was used for comparison of the intervillous circulation between groups. The growth of the yolk sac was considered statistically significant between gestational weeks 6 and 9, being most prominent between 9 and 10 weeks of gestation. Vascularity of the yolk sac, characterized by low velocity and absence of diastolic flow, was demonstrated in 67 per cent of normal pregnancies. Yolk sac blood flow was detected in 19 per cent of the patients with missed abortion. Doppler analysis of the intervillous circulation demonstrated decreased peak velocity of the continuous flow in patients with missed abortion for gestational weeks 11 and 12. It is concluded that progressive decrease of yolk sac vascularity coincides with visualization of more prominent colour-coded areas within the intervillous space. In patients with missed abortion, such changes do not occur.

Early pregnancy assessment with transvaginal ultrasound scanning.

OBJECTIVE: To establish normal parameters in early pregnancy through transvaginal ultrasonography so that gestational age can be determined and to correlate the sonographic findings with serum human chorionic gonadotropin (hCG) levels calibrated against the first international reference preparation standard. SETTING: Infertility clinic. PATIENTS: Thirty-five women with normal intrauterine pregnancy. INTERVENTIONS: Serial measurement of the serum hCG level and the diameter of the gestational sac through transvaginal ultrasonography. MAIN RESULTS: The gestational sac could not be visualized when the hCG level was less than 1100 IU/L. The average growth rate of the sac was 0.9 mm/d. The threshold values for sac diameter, serum hCG level and gestational age below which the yolk sac was not visible were 3.7 mm, 1900 IU/L and 36 days respectively; the corresponding values above which the yolk sac was always visible were 6.7 mm, 5800 IU/L and 40 days. The threshold values below which cardiac activity was not visible were 8.3 mm, 9200 IU/L and 41 days respectively, and the corresponding values above which cardiac activity was always visible were 14.0 mm, 24,000 IU/L and 46 days. The mean gestational ages and the 95% confidence and prediction intervals were tabulated so that measurement of the gestational sac diameter could be used to estimate gestational age early in normal pregnancy. CONCLUSIONS: Transvaginal ultrasonography enables detection of an intrauterine sac and reliable estimation of gestational age on the basis of sac dimensions before an embryo can be seen.