Hormonal and natural contraceptives: a review on efficacy and risks of different methods for an informed choice.

The debate about contraception has become increasingly important as more and more people seek safe and effective contraception. More than 1 billion women of reproductive age worldwide need a method of family planning, and wellbeing, socio-economic status, culture, religion and more influence the reasons why a woman may ask for contraception. Different contraceptive methods exist, ranging from 'natural methods' (fertility awareness-based methods - FABMs) to barrier methods and hormonal contraceptives (HCs). Each method works on a different principle, with different effectiveness.FABMs and HCs are usually pitted against each other, although it's difficult to really compare them. FABMs are a valid alternative for women who cannot or do not want to use hormone therapy, although they may have a high failure rate if not used appropriately and require specific training. HCs are commonly used to address various clinical situations, although concerns about their possible side effects are still widespread. However, many data show that the appropriate use of HC has a low rate of adverse events, mainly related to personal predisposition.The aim of this review is to summarize the information on the efficacy and safety of FABMs and HCs to help clinicians and women choose the best contraceptive method for their needs.

Cardiac function in fetal growth restriction.

Fetal growth restriction (FGR) is defined as the inability of the fetus to reach its growth potential. According to the onset of the disease is defined early (<32 weeks) or late (≥32 weeks). FGR is associated with an increased risk of adverse short- and long-term outcomes, including hypoxemic events and neurodevelopmental delay compared to normally grown fetuses and increased risk of complications in the infanthood and adulthood. The underlying cause of FGR is placental insufficiency leading to chronic fetal hypoxia that affects cardiac hemodynamic with different mechanism in early and late onset growth restriction. In early onset FGR adaptive mechanisms involve the diversion of the cardiac output preferentially in favor of the brain and the heart, while abnormal arterial and venous flow manifest in the case of further worsening of fetal hypoxia. In late FGR the fetal heart shows a remodeling of its shape and function mainly related to a reduction of umbilical vein flow. In this review we discuss the modifications occurring at the level of the fetal cardiac hemodynamic in fetuses with early and late FGR.

Correlation between Subpubic Arch Angle and Mode of Delivery in Large-for-Gestational-Age Fetuses.

OBJECTIVES: A narrow subpubic arch angle (SPA) has been associated with a higher risk of operative delivery and prolonged labor. The aim of this study was to evaluate the correlation between SPA and labor outcome in a cohort of women delivering a large-for-gestational-age (LGA) fetus. METHODS: An observational study involving two Italian tertiary centers (Parma and Rome) was carried out. Nulliparous women referred to the antepartum clinic between 35 and 39 weeks due to an increased risk of having an LGA fetus at birth were prospectively selected for the study purpose. Within the study cohort, SPA measurements were obtained by means of transperineal 3D ultrasound. Elective caesarean section and birth weight below 3,750 g represented exclusion criteria. In the final study group, SPA values were compared between the patients who underwent spontaneous vaginal delivery (SVD) and those who were submitted to unplanned obstetric intervention (UOI) due to prolonged or arrested labor (vacuum delivery or caesarean section). RESULTS: Overall, 129 women were included, and the mean birthweight of the neonates was 4,066 ± 263.03 g. SVD occurred in 63 patients (48.8%), whereas UOI due to prolonged or arrested labor was performed in 66 (51.2%), including 21 cases of vacuum delivery and 45 caesarean sections. The SPA was significantly smaller among women who underwent UOI than in those who achieved SVD (107.9 ± 13.4 vs. 120.7 ± 9.4°, p < 0.001). Furthermore, SPA width was inversely correlated with labor length (p < 0.001). Multivariable logistic regression analysis showed that a smaller SPA (OR 1.091, 95% CI 1.051-1.134, p < 0.001) and an increased birthweight (OR 1.002, 95% CI 1.000-1.004, p = 0.037) were independent risk factors for operative delivery. CONCLUSION: SPA measurement before labor is helpful in predicting the risk of operative delivery due to prolonged or arrested labor among nulliparous women delivering LGA fetuses.

Biomarkers for predicting spontaneous preterm birth: an umbrella systematic review.

OBJECTIVE: To identify all systematic reviews investigating the role of maternal and fetal biomarkers for predicting spontaneous preterm birth (SPTB). METHODS: Medline and Web of Sciences databases were searched electronically. Studies exploring the association between maternal biomarkers and spontaneous delivery were considered suitable for inclusion. A synthesis of the systematic reviews was performed with the umbrella methodology. Statistical measures of association (Odd ratio, OR, relative risk, RR) and predictive accuracy (sensitivity, specificity, positive and negative likelihood ratios were used to synthesize results of the included studies. RESULTS: 21,614 articles were identified, 542 were assessed with respect to their eligibility for inclusion and 14 systematic reviews included. Cervical fibronectin was the biomarkers which showed the highest strength of association with the occurrence of SPTB (delivery within 24 h OR 7, 95%CI 3-17; delivery <7 days (OR 12, 95%CI 8-16). Maternal serum alpha fetoprotein, was associated with an OR of 4 and 3 for early and late SPTB. C-reactive protein had an OR of 2 (95%CI 1-2) and 8 (95%CI 4-16) when detected in maternal plasma and amniotic fluid, respectively. Among cytokines, interleukin-6 had an OR and an LR + for SPTB of 2 and 12 when detected in maternal serum. CONCLUSIONS: Cervical fetal fibronectin, alpha fetoprotein, C- reactive protein and interleukin 6 can have an overall good diagnostic accuracy in identifying pregnancies at risk of SPTB. Large prospective studies in different sub-set of women are needed to ascertain whether the combination of different serological and imaging marker can improve antenatal prediction of this condition.

Fetal head circumference and subpubic angle are independent risk factors for unplanned cesarean and operative delivery.

INTRODUCTION: The aim of this study was to ascertain whether combined ultrasound assessment of fetal head circumference (HC) and maternal subpubic angle (SPA) prior to the onset of labor may predict the likelihood of an unplanned operative delivery (UOD) in nulliparous women at term. MATERIAL AND METHODS: Prospective cohort study of singleton pregnancies in cephalic presentation. Pregnancies experiencing UOD secondary to fetal distress were excluded. HC was assessed transabdominally and SPA values were obtained from a reconstructed coronal plane on three-dimensional (3D) ultrasound performed translabially at 36-38 weeks of gestation. Maternal characteristics, HC expressed as multiple of median, and SPA were compared according to the mode of delivery. Logistic regression and receiver operating characteristics curve analyses were used to analyze the data. RESULTS: 597 pregnancies were included in the study. Spontaneous vaginal delivery occurred in 70.2% of the cases and UOD was required in 29.8%. There was no difference in pregnancy characteristics and birthweight between women who had a spontaneous vaginal birth compared with UOD. The HC multiple of median was larger (1.00 ± 0.02 vs. 1.03 ± 0.02, p ≤ 0.0001), whereas SPA was narrower in the UOD group (124.02 ± 13.64 vs. 102.61 ± 16.13, p ≤ 0.0001). At logistic regression, SPA (OR 0.91, 95% CI 0.89-0.93), HC multiple of median (OR 1.13, 95% CI 1.09-1.17) and maternal height (OR 0.95, 95% CI 0.92-0.99) were independently associated with UOD. When combined, the diagnostic accuracy of a predictive model integrating HC, SPA and maternal height was highly predictive of UOD with an area under the curve of 0.904 (95% CI 0.88-0.93). CONCLUSIONS: Ultrasound assessment of fetal HC and maternal SPA after 36 weeks of gestation can identify a subset of women at higher risk of UOD during labor, for whom early planned delivery might be beneficial.

Computerised analysis of antepartum foetal heart parameters: New reference ranges.

We selected 4012 cCTG records (one trace for each patient) performed in healthy pregnancies from 30th to 42nd gestational week using foetal heart rate (FHR), short-term variability (STV), long-term irregularity (LTI), Delta, approximate entropy (ApEn), spectral components as low frequency (LF), median frequency (MF), high frequency (HF) and LF/(HF + MF) ratio were analysed. Reference nomograms were created and sensitivity and specificity for the prediction of foetal compromise were calculated which were 90% and 89%, respectively. Changes of cCTG parameters according to gestational week were evaluated: FHR (r = -.65) and LF (r = -.87) showed a statistically significant reduction (p < .05) with gestational age. STV (r = .59), LTI (r = .69), Delta (r = .67), and MF (r = .88) showed a statistically significant increase (p < .05) with gestational age. In contrast, for ApEn (r = -.098), HF (r = .14) and LF/(HF + MF) ratio (r = -.47) a non-statistically significant change was found (p > .05). The identification of reference ranges for cCTG indexes in according to gestational age could provide a more objective examination of cCTG trace.

5D CNS+ Software for Automatically Imaging Axial, Sagittal, and Coronal Planes of Normal and Abnormal Second-Trimester Fetal Brains.

The purpose of this study was to test new 5D CNS+ software (Samsung Medison Co, Ltd, Seoul, Korea), which is designed to image axial, sagittal, and coronal planes of the fetal brain from volumes obtained by 3-dimensional sonography. The study consisted of 2 different steps. First in a prospective study, 3-dimensional fetal brain volumes were acquired in 183 normal consecutive singleton pregnancies undergoing routine sonographic examinations at 18 to 24 weeks' gestation. The 5D CNS+ software was applied, and the percentage of adequate visualization of brain diagnostic planes was evaluated by 2 independent observers. In the second step, the software was also tested in 22 fetuses with cerebral anomalies. In 180 of 183 fetuses (98.4%), 5D CNS+ successfully reconstructed all of the diagnostic planes. Using the software on healthy fetuses, the observers acknowledged the presence of diagnostic images with visualization rates ranging from 97.7% to 99.4% for axial planes, 94.4% to 97.7% for sagittal planes, and 92.2% to 97.2% for coronal planes. The Cohen κ coefficient was analyzed to evaluate the agreement rates between the observers and resulted in values of 0.96 or greater for axial planes, 0.90 or greater for sagittal planes, and 0.89 or greater for coronal planes. All 22 fetuses with brain anomalies were identified among a series that also included healthy fetuses, and in 21 of the 22 cases, a correct diagnosis was made. 5D CNS+ was efficient in successfully imaging standard axial, sagittal, and coronal planes of the fetal brain. This approach may simplify the examination of the fetal central nervous system and reduce operator dependency.

Are There Differences in Placental Volume and Uterine Artery Doppler in Pregnancies Resulting From the Transfer of Fresh Versus Frozen-Thawed Embryos Through In Vitro Fertilization.

OBJECTIVE: To compare uterine artery pulsatility index (PI) and 3-dimensional (3D) placental volume values in first-trimester pregnancies conceived naturally or through in vitro fertilization (IVF) technique using either fresh or cryopreserved embryo and to relate these measurements with preeclampsia (PE) development. METHODS: Uterine artery PI and placental volume were measured at 11 + 0 to 13 + 6 weeks of gestation in 266 IVF pregnancies (139 women with fresh embryo and 127 women with frozen-thawed embryo transfer) and in 266 spontaneously conceived pregnancies matched for maternal age. Nulliparous women with singleton pregnancies were recruited. The mean, highest, and lowest uterine artery PI and placental volume values measured were converted to multiples of the expected normal median (MoM) adjusted for gestational age. The MoM values of IVF pregnancies were compared with those of the naturally conceived group and related to PE development. RESULTS: No differences were found in uterine artery PI MoM between the 3 groups. Placental volume was significantly lower than in both IVF groups when compared to the controls (fresh embryo IVF Z = 9.33; P ≤ .0001; frozen-thawed embryos IVF Z = 3.1; P = .04). The IVF pregnancies with fresh embryos showed placental volume MoM values significantly lower than in the frozen-thawed embryo IVF pregnancies (U = 5.4; P ≤ .0001). In fresh embryo IVF pregnancies developing PE placental volume values resulted lower than in the normotensive ones (U = 2.11; P = .03), while no differences were found for uterine artery PI values. CONCLUSION: First-trimester placental volume, as assessed by 3D ultrasound, is reduced in IVF pregnancies, and these differences are more marked in those obtained with fresh embryos than those obtained with cryopreservation. This may explain the better obstetrical and perinatal outcomes occurring with the former technique.

The feasibility of using 5D CNS software in obtaining standard fetal head measurements from volumes acquired by three-dimensional ultrasonography: comparison with two-dimensional ultrasound.

OBJECTIVE: To evaluate the performance of a new software (5D CNS) developed to automatically recognize the axial planes of the fetal brain from three-dimensional volumes and to obtain the basic standard biometric measurements. The accuracy, reproducibility, and time required for analysis of 5D CNS were compared with that of two-dimensional (2D) ultrasound. METHODS: This was a prospective study of 120 uncomplicated singleton pregnancies undergoing routine second trimester examination. For every pregnancy standard biometric measurements including biparietal diameter, head circumference, distal lateral ventricle width, transverse cerebellar diameter and cisterna magna width were obtained using 2D ultrasound and three-dimensional (3D) ultrasound with 5D CNS software. Reliability and agreement of the two techniques were evaluated using intraclass correlation coefficients (ICCs) and proportionate Bland-Altman plots were constructed. The time necessary to complete the measurements with either technique was compared and intraobserver and interobserver agreements of measurements calculated. RESULTS: In 118/120 (98.3%), 5D CNS successfully reconstructed the axial diagnostic planes and calculated all the basic biometric head and brain measurements. The agreement between the two techniques was high for all the measurements considered (all ICCS > 0.920). The time necessary to measure the biometric variables considered was significantly shorter with 5D CNS (54 versus 115 s, p < 0.0001) than with 2D ultrasonography. No significant differences were found in 5D CNS repeated measurements obtained either by the same observer or by two independent observers. CONCLUSION: 5D CNS software allows us to obtain reliable biometric measurements of the fetal brain and to reduce the examination time. Its application may improve work-flow efficiency in ultrasonographic practices.

Ultrasonographic assessment of cervical length in pregnancies scheduled for a cesarean delivery: prediction of early spontaneous onset of labor.

AIM: To investigate whether the cervical length measured by transvaginal ultrasound at 35 to 36 weeks of gestation is predictive of spontaneous early onset of labor in pregnancies scheduled for elective cesarean section (CS). STUDY DESIGN: This was a prospective observational study on 167 women scheduled for elective CS at 39 weeks of gestation. The cervical length was measured ultrasonographycally at 35 to 36 weeks of gestation and the pregnancies characteristics were recorded. The presence or absence of spontaneous onset of labor before the time scheduled for elective CS was related to cervical length and pregnancies characteristics. RESULTS: Of the 167 pregnancies enrolled, 25 (14.97%) underwent early spontaneous onset of labor before the time scheduled for the elective CS. The cervical length was significantly shorter in these women when compared with those delivering with an elective CS (21 vs. 30 mm z=5.49 P<0.0001). The presence of ≥2 previous CS as an indicator for elective CS resulted a significant predictor of early onset of labor in univariate analysis (P=0.01). Multivariate logistic regression analysis showed that cervical length (adjusted odds ratio 1.40; 95% confidence interval (CI) 1.22-1.61; P≤0.0001) was the only predictor for the early onset of labor. The area under the receiver-operating characteristics curve for the prediction of early onset of labor was 0.844 (95% CI 0.738-0.950) for cervical length as test variable. Kaplan-Meier analysis demonstrated that a cervical length <24 mm was significantly associated with a short time interval to delivery (log rank test χ2=99,98; P≤0.0001). CONCLUSION: Cervical length at 35-36 weeks of gestation provides information about the likelihood of spontaneous early onset of labor in pregnancies scheduled for CS and may be useful in individualizing the gestational age for elective CS.

Does fetal macrosomia affect umbilical artery Doppler velocity waveforms in pregnancies complicated by gestational diabetes?

OBJECTIVES: We aimed to establish whether macrosomic fetuses in pregnancies complicated by gestational diabetes (GDM) show different Pulsatility Index (PI) values in umbilical artery (UA) than in non-macrosomic fetuses. METHODS: We considered 106 pregnant women with GDM. Doppler recordings of UA-PI were performed at 34-41 weeks and related to neonatal birthweight. Pregnancies were divided in two groups according to birthweight, macrosomic group (>4000 g) and controls (<4000 g), and according to birthweight centile, >90th centile and <90th centile. Differences in UA-PI and maternal and fetal characteristics between groups were tested. RESULTS: Mean UA-PI was significantly lower in newborns with birthweight >4000 g than in controls (PI = 0.69; 95% CI 0.64-0.74 versus PI = 0.87; 95% CI 0.84-0.90, p < 000.1). Mean UA-PI was significantly lower in newborns with birthweight centile >90th centile than in controls (PI = 0.79; 95% CI 0.74-0.84 versus PI = 0.87; 95% CI 0.83-0.90; t = 2.653; p = 0.01). Linear regression analysis revealed a significant correlation between UA-PI and neonatal birthweight and between UA-PI and neonatal birthweight centile. CONCLUSIONS: Macrosomic fetuses of pregnancies complicated by GDM show lower values of UA-PI compared with controls. Despite UA-PI results, a variable related to macrosomia its role in the management of these pregnancies remains to be established.

Modelling umbilical vein blood flow normograms at 14-40 weeks of gestation by quantile regression analysis.

OBJECTIVE: To construct reference limits for gestation of umbilical vein blood flow (UVBF) in normal singleton pregnancies between 14 and 40 weeks of gestation using quantile regression. METHODS: We ultrasonographycally examined 852 fetuses from low-risk pregnancies between 16 and 40 weeks of gestation in a prospective cross-sectional study. UV diameter and time-averaged maximum velocity (TAMXV) were measured in UV intra-abdominal portion by real time and Doppler ultrasonography. A semi-automatic measurement software was used to obtain UV diameter values. UVBF was then calculated from UV diameter and TAMXV measurements and expressed both as absolute value and as value normalized for fetal abdominal circumference (UVBF/AC). Individual centile values of the variables investigated were established by quantile regression in the gestational interval considered. In 50 cases UVBF was measured twice by the same investigator or by a second investigator and the intra- and inter-observer agreement were calculated. RESULTS: A significant increase in UV diameter, TAMXV, UVBF absolute value and UVBF/AC was evidenced in the gestational period considered. Growth charts were established based on these measurements. The intra- and inter-observer intraclass correlation coefficients resulted as 0.92 (0.87-0.96) and 0.89 (0.84-0.97), respectively, for UBVF. CONCLUSIONS: In this study we constructed UVBF charts using quantile regression in a large cohort of low-risk pregnancies. These charts offer the advantage of specific estimated regression parameters for each percentile, better defining the normal range of UVBF. This promises to be useful in the diagnosis and management of fetuses with abnormal fetal growth.

Viewing rate and reference ranges for papillary muscle areas of the fetal heart using four-dimensional ultrasound in the rendering mode.

OBJECTIVES: The aims of this study were to assess the viewing rate and determine reference ranges ​​for the papillary muscle areas in the fetal atrio-ventricular valves using four-dimensional (4D) ultrasound and spatio-temporal image correlation (STIC) in the rendering mode. METHODS: This cross-sectional prospective study included 310 4D STIC volume data sets of normal fetuses between 18 weeks 0 day and 34 weeks 0 day of gestation. The papillary muscles were antero-lateral (MPAL) and postero-medial (MPPM) to the mitral valve and antero-superior (MPAS), inferior (MPI) and septal (MPS) to the tricuspid valve. Polynomial regressions were built to determine the reference ranges, and adjustments were made using the determination coefficient (R(2) ). To assess inter-observer reproducibility, the intra-class correlation coefficient (ICC) was used. RESULTS: Identification of the papillary muscles was possible in 89.3% patients. The best-fit regression equations between papillary muscle areas and gestational age were second degree. The inter-observer reproducibility was good (ICC: 0.98 to MPAS, 0.97 to MPI, 0.98 to MPS, 0.98 to MPAL and 0.97 to MPPM). CONCLUSIONS: Identification of the papillary muscles of the fetal valves was possible in most of the 4D STIC volume data sets, enabling the determination of reference ranges using the rendering mode. The reference ranges ​​for the papillary muscle areas were determined.

First trimester placental volume and three dimensional power doppler ultrasonography in type I diabetic pregnancies.

OBJECTIVE: This study aimed to investigate the placental volume and three dimensional (3D) power Doppler vascularization in type I diabetic pregnancies during the first trimester METHODS: 3D-power Doppler ultrasonography of the placenta was performed at 11+0-13+6 weeks in 32 pregnancies complicated by type I diabetes. Placental volume, vascularization index (VI), flow index (FI), and vascularization flow index (VFI) were calculated using a standardized setting. RESULTS: In nine pregnancies, a poor first trimester glycemic control was present as expressed by HbA1c levels ≥ 7%, whereas in the remaining 23 mothers, the HbA1c concentrations were <7%. No differences were found in the placental volumes of diabetic mothers when compared with reference limits. 3D Doppler placental vascular indices were significantly higher in diabetic mothers (VI delta value 0.99, p=0.0012; FI delta value 0.64, p=0.0008; VFI delta value 1.28, p=0.0039) when compared with reference limits. Pregnancies with HbA1c ≥ 7% exhibited higher placental vascular indices when compared with diabetic mothers with better glycemic control. CONCLUSIONS: In type I diabetic mothers, placental vascular indices are increased and these modifications are more evident in pregnancies with poor first trimester glycemic control.

Are there any differences in three-dimensional placental vascular indices obtained using conventional power Doppler and high-definition flow imaging?

OBJECTIVE: The purpose of this study was to determine whether there are differences in values and reproducibility of three-dimensional (3D) vascular indices obtained on placental volumes using power Doppler (PD) or high-definition flow imaging (HDFI) techniques. METHODS: A prospective study was performed on 121 uncomplicated singleton pregnancies at 11 + 0 to 13 + 6 weeks of gestation. Two placental volumes were acquired from each pregnancy. Vascularization index (VI), flow index (FI) and vascularization flow index (VFI) were then analyzed and compared. In order to assess the reproducibility of the measurements, two additional placental volumes obtained with both PD and HDFI were acquired in 31 pregnancies and the agreement assessed by intraclass correlation coefficients. Inter-observer variability was assessed by analyzing all the volumes by two observers blinded to each other's. RESULTS: A significant relationship was observed between the vascular indices values obtained with the two techniques (VI Pearson's r=0.891 p<0.001; FI r=0.769 p<0.001; VFI r=0.847 p<0.001). The median values of VI, FI and VFI were significantly higher when obtained with HDFI imaging. In serial recordings, the ICCs resulted higher when volumes were acquired with HDFI rather than with PD techniques. Similarly, HDFI demonstrated a higher inter-observer reproducibility. CONCLUSIONS: 3D vascular indices calculated using HDFI are higher than those calculated using conventional PD. Although the relationship between the two methods is high, HDFI shows a better reproducibility suggesting its potential clinical application.

Assessment of cerebellar vermis biometry at 18-32 weeks of gestation by three-dimensional ultrasound examination.

OBJECTIVE: The purpose of this study was to construct reference limits for cerebellar vermis (CV) dimensions measured on images reconstructed from three-dimensional (3D) ultrasonography and to evaluate these measurements reproducibility. METHODS: 3D ultrasound volumes were acquired transabdominally from an axial view of the fetal head in 342 fetuses cross-sectionally studied between 18 to 32 weeks of gestation. Offline analysis of fetal brain midsagittal plane was used to evaluate length and area of CV. The agreement between two-dimensional (2D) and 3D measurements as well as the interobserver variability in 3D measurements were assessed by interclass correlation coefficients (ICC). RESULTS: Adequate visualization of the midsagittal plane was obtained in 96.7% of the fetuses. CV length (r = 0.89, p < 0.0001) and CV area (r = 0.93, p < 0.0001) showed a significant linear growth with gestation. A good agreement was found between measurements from either 2D or 3D ultrasound views (CV length ICC 0.943, CV area ICC 0.940) as well as between measured obtained by different observers (CV length ICC 0.965, CV area ICC 0.905). CONCLUSIONS: Measurements of the CV can be obtained from the midsagittal plane of fetal brain reconstructed from 3D volumes acquired transabdominally. The constructed nomograms may facilitate the diagnosis of cerebellar abnormalities.

Collaborative study on 3-dimensional sonography for the prenatal diagnosis of central nervous system defects.

OBJECTIVES: Prenatal diagnosis of central nervous system (CNS) anomalies by 2-dimensional sonography is challenging because of difficulties in obtaining complete visualization of the fetal brain during routine examinations, which is necessary for identification of its axial, coronal, and sagittal planes. Three-dimensional (3D) sonography has been introduced as a tool for studying the fetal CNS because of its ability to facilitate examinations of the fetal brain. The objective of this study was to determine inter-center agreement in diagnosing CNS defects by review of 3D volume data sets. METHODS: This study included 11 centers with expertise in 3D fetal neurosonography. A total of 217 fetuses with and without confirmed CNS defects were scanned after 18 weeks' gestation, and their volume data sets were uploaded onto a centralized file transfer protocol server and later analyzed by all of the centers. Intercenter agreement was determined using a κ statistic for multiple raters. RESULTS: All volumes were made anonymous and sent to the centers for blinded analysis with the exception of the data sets they had themselves previously uploaded. For identification of fetuses with CNS defects, the sensitivity, specificity, positive and negative predictive values, and false-positive and -negative rates were 93.3%, 96.5%, 96.5%, 93.3%, 3.5%, and 6.7%, respectively. No differences were found in the efficacy of the diagnostic indices according to either the route of acquisition (transabdominal or trans-vaginal) or the gestational age at diagnosis (18-24 or >24 weeks). Intercenter agreement was excellent (κ = 0.92; 95% confidence interval, 0.88-0.97). CONCLUSIONS: Among centers with technical expertise, remote review of 3D sonographic volumes of the fetal CNS resulted in an accurate and reliable method for diagnosis of fetal brain malformations.

Assessment of corpus callosum biometric measurements at 18 to 32 weeks' gestation by 3-dimensional sonography.

OBJECTIVES: The purposes of this study were to construct reference limits for corpus callosum dimensions measured on images reconstructed from 3-dimensional (3D) sonography and to evaluate the reproducibility of these measurements. METHODS: Three-dimensional sonographic volumes were acquired transabdominally from an axial view of the head in 361 fetuses cross-sectionally studied at 18 to 32 weeks' gestation. Offline analysis of the fetal brain midsagittal plane was used to evaluate the length and area of the corpus callosum and corpus callosum-cavum septi pellucidi complex. The agreement between 2-dimensional (2D) and 3D measurements as well as the interobserver variability in 3D measurements were assessed by interclass correlation coefficients (ICCs). RESULTS: Adequate visualization of the midsagittal plane was obtained in 98.1% of the fetuses. A clear distinction between the corpus callosum and cavum septi pellucidi was obtained in 35.7% of the fetuses, whereas in the remaining cases, the corpus callosum-cavum septi pellucidi complex was visualized as a single echogenic structure. The corpus callosum-cavum septi pellucidi complex length (r = 0.806; P < .0001), corpus callosum-cavum septi pellucidi complex area (r = 0.920; P < .0001), and corpus callosum area (r = 0.713; P < .0001) showed a significant linear growth with gestation. A good agreement was found between measurements from both 2D and 3D sonographic views (corpus callosum length ICC, 0.916) as well as between measurements obtained by different observers (corpus callosum-cavum septi pellucidi complex length ICC, 0.936; corpus callosum-cavum septi pellucidi complex area ICC, 0.931). CONCLUSIONS: Measurements of the corpus callosum and cavum septi pellucidi can be obtained from the midsagittal plane of the fetal brain reconstructed from 3D volumes acquired transabdominally. The constructed nomograms may facilitate the diagnosis of corpus callosum abnormalities.