-
Ultrasound in Obstetrics and Gynecology 05/2013; · 3.01 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Objective: To examine the possible relationship between maternal and fetal characteristics and pregnancy outcomes on fetal and maternal cell-free (cf) DNA in maternal plasma at 11-13 weeks' gestation. Methods: cfDNA was extracted from maternal plasma of 1,949 singleton pregnancies and chromosome-selective sequencing was used to determine the proportion of cfDNA and total cfDNA counts which was of fetal and maternal origin. Multivariate regression analysis was used to determine whether specific maternal and fetal characteristics and pregnancy complications, such as preeclampsia (PE), early spontaneous preterm birth (SPB) and delivery of small for gestational age (SGA) neonates, were significant predictors of fetal and maternal cfDNA in maternal plasma. Results: The fetal and maternal cfDNA plasma concentration increased with serum pregnancy-associated plasma protein-A and free β-human chorionic gonadotropin level, was higher in women of Afro-Caribbean and East-Asian racial origin than in Caucasians, and lower in smokers, but it was not significantly altered in pregnancies complicated by PE, SPB or SGA. The fetal cfDNA level was inversely related to maternal weight and uterine artery pulsatility index, and maternal cfDNA increased with maternal weight. Conclusions: The fetal and maternal cfDNA level in maternal plasma is affected by maternal and fetal characteristics, but it is not altered in pregnancy complications.
Fetal Diagnosis and Therapy 03/2013; · 1.05 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Objective: To examine aortic systolic blood pressure (SBP(Ao)), pulse wave velocity (PWV) and augmentation index (adjusted to a heart rate of 75 beats per minute, AIx-75) at 11-13 weeks' gestation in pregnancies delivering small for gestational age (SGA) neonates with and without preeclampsia (PE). Methods: At 11+0 to 13+6 weeks' gestation, maternal history was recorded and PWV, AIx-75, SBP(Ao), uterine artery pulsatility index (PI) and maternal serum pregnancy-associated plasma protein-A (PAPP-A) were measured. We compared women with (n = 337) and without (n = 48) PE that delivered SGA neonates with unaffected controls (n = 6,429). Results: In the SGA group without PE, compared to unaffected controls, there was no significant difference in AIx-75 (1.03 vs. 1.00 multiple of the median, MoM), PWV (0.98 vs. 1.00 MoM) or SBP(Ao) (1.01 vs. 1.00 MoM), but uterine artery PI was increased (1.10 vs. 1.00 MoM) and PAPP-A decreased (0.85 vs. 1.00 MoM). In SGA with PE, compared to unaffected controls, there was increased AIx-75 (1.13 vs. 1.00 MoM), SBP(Ao) (1.09 vs. 1.00 MoM), uterine artery PI (1.40 vs. 1.00 MoM) and decreased PAPP-A (0.72 vs. 1.00 MoM), but no significant difference in PWV (1.05 vs. 1.00 MoM). Conclusion: In pregnancies with SGA neonates, impaired placentation is reflected in low PAPP-A and high uterine artery PI at 11-13 weeks' gestation. In the SGA group with PE, but not in those without PE, there is increased SBP(Ao) and AIx-75.
Fetal Diagnosis and Therapy 09/2012; · 1.05 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Ultrasound examination of the conceptus and the uterine blood supply between 11 and 13 weeks' gestation provides important information about the state of the pregnancy at that point in time and about its future progress. Nuchal translucency measurement in conjunction with maternal serum markers (free-beta-human chorionic gonadotropin and pregnancy-associated plasma protein-A), has been shown to be a highly effective method for screening for aneuploidy. This is further improved by the addition of other more recently discovered first trimester ultrasound markers resulting in detection rates that exceed 90% with a false positive rate of 2.5%. Many fetal structural anomalies can be detected at this gestational age. Recently described first trimester evaluation of the posterior brain (intracranial translucency (IT)) provides an effective screening tool for the presence of open neural tube defects. Doppler measurement of the pulsatility index in the uterine arteries in conjunction with maternal history and examination as well as maternal serum biochemistries helps to accurately establish the risk of developing preeclampsia.
Ceska gynekologie / Ceska lekarska spolecnost J. Ev. Purkyne 04/2012; 77(2):92-104.
-
[show abstract]
[hide abstract]
ABSTRACT: To assess the potential value of maternal serum alpha-fetoprotein (AFP) at 11-13 weeks' gestation in early screening for fetal neural tube defects (NTDs).
Maternal serum AFP at 11-13 weeks' gestation was measured in 32 cases of fetal NTDs, including 18 cases of acrania and 14 cases of spina bifida, and 1,500 unaffected controls. The measured serum AFP was converted into multiple of the expected median (MoM) after adjustment for gestational age and maternal characteristics and Mann-Whitney test was used to determine the significance of difference in the mean MoM of serum AFP in the NTD group to that in the controls.
The mean AFP MoM in the NTD group (1.76, 95% CI 1.39-2.23) was significantly higher than in the controls (p < 0.0001). The mean AFP MoM was not significantly different between the cases of acrania and cases of spina bifida (1.78 vs. 1.75; p = 0.722). The detection rates of NTD in screening by serum AFP were 50.0% (95% CI 31.9-68.1) and 37.5% (95% CI 21.1-56.3) at fixed false-positive rates of 10 and 5%, respectively.
Measurement of maternal serum AFP at 11-13 weeks' gestation may be useful in screening for fetal NTDs.
Fetal Diagnosis and Therapy 02/2012; 31(2):109-14. · 1.05 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: This study is aimed to determine whether the maternal serum levels of vitamin D in the first trimester of pregnancy are altered in cases that develop preeclampsia (PE) and whether the levels are related to biochemical and biophysical markers of impaired placental perfusion and function. Maternal total serum vitamin D, pregnancy-associated plasma protein-A (PAPP-A), uterine artery pulsatility index (PI) and mean arterial pressure (MAP) were measured at 11-13 week gestation in 90 cases that developed PE, including 30 that required delivery before 34 weeks (early PE) and 1000 unaffected controls. The median values of vitamin D, PAPP-A, uterine artery PI and MAP expressed as a multiple of the unaffected median (MoM), in the patients developing early PE and late PE were compared with the controls. There was no significant difference in the median serum vitamin D MoM or raw values within the outcome groups (P=141 and P=0.231, respectively) whereas the median PAPP-A MoM, uterine PI MoM and MAP MoM were significantly different (P=0.031, P=0.001 and P<0.0001, respectively). Serum PAPP-A was decreased in both early PE and late PE (0.54 and 0.88 versus 1.03 MoM, P<0.0001 and P=0.010, respectively), MAP was increased in both early PE and late PE (1.09 and 1.06 versus 0.99 MoM, P<0.0001 and P<0.0001, respectively) and uterine artery PI was increased in early PE but not in late PE (1.32 and 1.12 versus 1.01 MoM, P<0.0001 and P=0.083, respectively). In pregnancies that subsequently develop PE maternal serum total vitamin D levels at 11-13 weeks are not altered.Journal of Human Hypertension advance online publication, 16 February 2012; doi:10.1038/jhh.2012.1.
Journal of human hypertension 02/2012; · 2.80 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To evaluate a novel ultrasound measurement, the prefrontal space ratio (PFSR), in second-trimester trisomy 21 and euploid fetuses.
Stored three-dimensional volumes of fetal profiles from 26 trisomy 21 fetuses and 90 euploid fetuses at 15-25 weeks' gestation were examined. A line was drawn between the leading edge of the mandible and the maxilla (MM line) and extended in front of the forehead. The ratio of the distance between the leading edge of the skull and that of the skin (d(1)) to the distance between the skin and the point where the MM line was intercepted (d(2)) was calculated (d(2)/d(1)). The distributions of PFSR in trisomy 21 and euploid fetuses were compared, and the relationship with gestational age in each group was evaluated by Spearman's rank correlation coefficient (r(s) ).
The PFSR in trisomy 21 fetuses (mean, 0.36; range, 0-0.81) was significantly lower than in euploid fetuses (mean, 1.48; range, 0.85-2.95; P < 0.001 (Mann-Whitney U-test)). There was no significant association between PFSR and gestational age in either trisomy 21 (r(s) = 0.25; 95% CI, - 0.15 to 0.58) or euploid (r(s) = 0.06; 95% CI, - 0.15 to 0.27) fetuses.
The PFSR appears to be a highly sensitive and specific marker of trisomy 21 in the second trimester of pregnancy.
Ultrasound in Obstetrics and Gynecology 02/2012; 40(3):293-6. · 3.01 Impact Factor
-
Prenatal Diagnosis 02/2012; 32(2):198-9; author reply 202-3. · 2.11 Impact Factor
-
Ultrasound in Obstetrics and Gynecology 01/2012; 39(1):2-6. · 3.01 Impact Factor
-
Ultrasound in Obstetrics and Gynecology 01/2012; 39(1):7-9. · 3.01 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To identify the best protocol for measurement of mean arterial pressure (MAP) in early pregnancy for the prediction of preeclampsia (PE).
This was a prospective study in singleton pregnancies attending for a routine hospital visit at 11-13 weeks' gestation when a minimum of four recordings of MAP were taken from each arm. The performance of screening for PE by different combinations of MAP was compared to the protocol of the National Heart Foundation of Australia (NHFA).
The MAP was measured in 587 (2.4%) cases that developed PE and in 22,900 that were unaffected by hypertensive disorders in pregnancy. The area under the receiver operating characteristic curve (AUROC) for prediction of PE by MAP as recommended by the NHFA protocol was 0.773 (95% CI 0.768-0.778). This AUROC was not significantly different from the AUROC obtained by the average MAP of the first three measurements from one arm (0.765, 95% CI 0.760-0.771) or the average of the first (0.766, 95% CI 0.760-0.771), the first two (0.771, 95% CI 0.766-0.777), or the first three measurements from the two arms (0.773, 95% CI 0.768-0.778).
Performance of screening for PE by taking the average of a minimum of two measurements from both arms is comparable to the NHFA protocol.
Fetal Diagnosis and Therapy 01/2012; 31(1):42-8. · 1.05 Impact Factor
-
Ultrasound in Obstetrics and Gynecology 12/2011; 38(6):609-12. · 3.01 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To investigate tracheal dimensional differences seen at birth following fetal endoscopic tracheal occlusion (FETO) in cases of severe congenital diaphragmatic hernia (CDH) and to report on their clinical follow-up.
In chest X-rays, taken within 48 h after birth, we measured the tracheal diameter at the level of the tracheal entry into the chest, 1 cm above the level of the carina and at middistance between these sites in 37 fetuses with severe CDH treated by FETO. These measurements were compared with those in 74 preterm and term neonates with no congenital lung abnormalities.
In the CDH group, compared to the controls, the tracheal diameter corrected for gestational age was significantly larger at all three levels of the trachea. Regression analysis showed that significant predictors of the tracheal diameter at the level of tracheal entry into the chest were the observed to expected (o/e) lung area to head circumference ratio (LHR) and the duration of tracheal occlusion. In the CDH group, postnatal follow-up until the age of 22 months (1-70) showed that 5 of 24 neonates had an effort-induced barking cough.
A large number of infants with severe CDH surviving after FETO have a degree of tracheomegaly that is associated with the severity of CDH as assessed by pre-FETO LHR. This tracheomegaly does not constitute an obvious clinical problem.
Prenatal Diagnosis 07/2011; 31(7):699-704. · 2.11 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To assess the accuracy of fetal echocardiography at 11-13 weeks performed by well-trained obstetricians using a high-frequency linear ultrasound transducer.
Fetal echocardiography was performed by obstetricians immediately before chorionic villus sampling for fetal karyotyping at 11-13 weeks. Digital videoclips of the examination stored by the obstetrician were reviewed offline by a specialist fetal cardiologist.
The obstetrician suspected 95 (95%) of the 100 cardiac defects identified by the fetal cardiologist and made the correct diagnosis in 84 (84%) of these cases. In 54 fetuses, the defect was classified as major and in 46 it was minor. In 767 (86.6%) cases, the heart was normal and in 19 (2.1%) the views were inadequate for assessment of normality or abnormality. A subsequent second-trimester scan in the normal group identified major cardiac defects in four cases. Therefore, the first-trimester scan by the obstetricians and cardiologists identified 54 (93.1%) of the 58 major cardiac defects.
A well-trained obstetrician using high-resolution ultrasound equipment can assess the fetal heart at 11-13 weeks with a high degree of accuracy.
Ultrasound in Obstetrics and Gynecology 03/2011; 37(3):296-301. · 3.01 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: This study was carried out to examine the performance of a contingent policy in first-trimester screening for trisomy 21, in which the estimated risk was first derived by a combination of maternal age, fetal nuchal translucency (NT) thickness, presence/absence of the nasal bone, blood flow in the ductus venosus or flow across the tricuspid valve, and biochemical testing was carried out only in those who were found to have an intermediate risk. We also examined the performance of a policy in which the estimated risk was first derived by a combination of maternal age and biochemical testing, and ultrasound examination was carried out only in those with an intermediate risk.
The data for this study were derived from prospective screening for trisomy 21 in singleton pregnancies, using, as markers, a combination of maternal age, fetal NT thickness and maternal-serum free β-human chorionic gonadotropin (β-hCG) and pregnancy-associated plasma protein-A (PAPP-A), in a one-stop clinic for first-trimester assessment of risk at 11 + 0 to 13 + 6 weeks of gestation. Assessment of the fetal nasal bone, ductus venosus flow and tricuspid flow were also routinely performed by appropriately trained sonographers. The performance of different screening policies was examined.
The study population consisted of 19 614 pregnancies with a normal karyotype or delivery of a phenotypically normal baby (euploid group) and 122 cases of trisomy 21. The best performance was achieved by a contingent policy in which first-stage screening was based on maternal age, fetal NT thickness and either tricuspid valve or ductus venosus blood flow, followed by biochemical testing only those with an intermediate risk, of 1 in 51 to 1 in 1000 (which constituted about 20% of the total). The performance of contingent screening in which first-stage testing relies on biochemistry was poorer than when first-stage screening was performed by ultrasound examination because, in order to achieve the same detection rate, the false-positive rate was twice as high.
Effective first-trimester screening for trisomy 21 can be achieved by a contingent policy in which first-stage testing is based on ultrasound examination and second-stage biochemical testing is carried out in only 20% of the patients.
Ultrasound in Obstetrics and Gynecology 11/2010; 36(5):542-7. · 3.01 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To examine the association between single umbilical artery (SUA) and cardiac defects and to determine whether patients with SUA require specialist fetal echocardiography.
Incidence and type of cardiac defects were determined in fetuses with SUA detected at routine second-trimester ultrasound examination.
A routine second-trimester scan was performed in 46 272 singleton pregnancies at a median gestation of 22 (range, 18-25) weeks and an SUA was diagnosed in 246 (0.5%). Cardiac defects were diagnosed in 16 (6.5%) of these cases, including 10 (4.3%) in a subgroup of 233 with no other defects and in six (46.2%) of the 13 with multiple defects. In 11 (68.8%) of the 16 cases with cardiac defects the condition was readily diagnosable by evaluating the standard four-chamber view and the views of the great arteries. In the remaining cases there was left persistent superior vena cava or small ventricular septal defect, where prenatal diagnosis may not be important because they are not associated with adverse outcome.
Although SUA is associated with an increased incidence of cardiac defects it may not be necessary to refer such patients for specialist fetal echocardiography because the defects are detectable by evaluating standard cardiac views that should be part of the routine second-trimester scan.
Ultrasound in Obstetrics and Gynecology 11/2010; 36(5):553-5. · 3.01 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: This study was carried out to determine the feasibility of defining the position of the right subclavian artery (RSA) by fetal echocardiography between 16 and 23 weeks of gestation, and the association between an aberrant right subclavian artery (ARSA) and chromosomal and cardiac defects.
We examined the position of the RSA in all patients who attended our unit for a fetal cardiac scan. The assessment was carried out using a transverse view of the fetal chest sweeping up from the level of the aortic arch, using color flow mapping. An ARSA was diagnosed when this vessel was not seen in the normal position and an arterial vessel was seen crossing behind the trachea towards the right arm, arising as a fourth branch of the aortic arch, at a lower level than normal.
The course of the RSA could be identified in more than 95% of the 2799 fetuses examined between 16 and 23 + 6 weeks of gestation. An ARSA was found in 43 fetuses. The incidence was 1.5% in normal fetuses, 28.6% in fetuses with trisomy 21, 18.2% in fetuses with trisomy 18 and 8% in fetuses with other chromosomal defects. There was an association between an ARSA and cardiac defects in seven of the 43 fetuses (16%), and three of these seven fetuses had a normal karyotype.
Assessment of the RSA by a fetal cardiologist is possible in almost all cases. The finding of an ARSA is much more common in fetuses with chromosomal defects, in particular trisomy 21 (where the prevalence of an ARSA was 29%), compared with euploid fetuses. Moreover, the presence of an ARSA may be associated with an increased incidence of intracardiac malformations. Examination of the position of the RSA is likely to become a routine ultrasound marker for chromosomal abnormalities in the second trimester of pregnancy.
Ultrasound in Obstetrics and Gynecology 11/2010; 36(5):548-52. · 3.01 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To estimate intersonographer and intrasonographer variance components of fetal nuchal translucency (NT) thickness measurement using the traditional manual approach and a new semi-automated system.
A semi-automated method was developed for measurement of the NT. In this method, the operator places an adjustable box over the relevant area at the back of the fetal neck. The system draws a line through the center of the nuchal membrane and another line at the edge of the soft tissue overlying the cervical spine. The system then identifies the largest vertical distance between the two lines. The images of 12 fetuses at 11-13 weeks of gestation satisfying the guidelines of The Fetal Medicine Foundation for measurement of NT were selected. They were exported in DICOM format from the ultrasound system, and four versions of each image were stored under different names. The resulting 48 images were presented in random order for electronic assessment. A total of 20 sonographers measured the NT in each set of 48 pictures, twice using the semi-automated system and twice using the manual system, according to a randomized block design. Within- and between-operator variance components were estimated. Relative biases were assessed by comparing the means from the two methods.
The estimated between-operator SD using the semi-automated method was 0.0149 mm compared with 0.109 mm for the manual method. The respective within-operator SD values were 0.05 mm and 0.126 mm. The intraclass correlation coefficients for different sonographers measuring the same images were 0.98 and 0.85 for the semi-automated method and the manual method, respectively.
The measurement of fetal NT is more reliable when a semi-automatic approach is used rather than the traditional manual method.
Ultrasound in Obstetrics and Gynecology 10/2010; 36(4):412-6. · 3.01 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The aims of this study were, first, to establish the agreement between digital and ultrasound assessment of occipital position and, second, to evaluate the repeatability of the measurements of head direction, angle of the middle line, progression distance and angle of progression in women in the second stage of labor.
Digital examination and then transabdominal ultrasound examination was performed on 50 women in the second stage of labor to determine the fetal occipital position. We also obtained three-dimensional (3D) blocks of the fetal head by transperineal sonography, and two experts in 3D ultrasound measured head direction, angle of the middle line, progression distance and angle of progression. Intraclass correlation coefficients with 95% CIs, and Bland-Altman analysis, were used to evaluate intraobserver and interobserver repeatability of measurements.
The fetal head position, determined by ultrasound examination, was occiput anterior in 33 (66%) cases and occiput lateral in 17 (34%) cases. Vaginal digital examination failed to identify the correct fetal head position by more than 45° in 33 (66%) cases. All four 3D ultrasound measurements were reproducible but the progression angle had the highest intraclass correlation coefficient for the same observer (0.94; 95% CI, 0.90-0.97) and for two different operators (0.84; 95% CI, 0.73-0.91). The progression angle was also the measurement for which smaller limits of agreement (LOA) were found in the Bland-Altman test, performed to calculate the intraobserver (bias 0.9; LOA, - 9.2 to 11.1%) and interobserver (bias 1.5; LOA, - 15.4 to 18.3%) variability.
Digital pelvic examination for determining the fetal head position during labor is not accurate. The most reproducible of the 3D measurements for progression of the fetal head in labor is the progression angle.
Ultrasound in Obstetrics and Gynecology 10/2010; 36(4):493-9. · 3.01 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To establish an algorithm for first-trimester combined screening for trisomy 21 with biochemical testing from 7 to 14 weeks' gestation and ultrasound testing at 11-13 weeks.
This was a multicenter study of 886 pregnancies with trisomy 21 and 222 475 unaffected pregnancies with measurements of free β-human chorionic gonadotropin (β-hCG) and pregnancy-associated plasma protein-A (PAPP-A) at 7-14 weeks' gestation. Multiple regression modeling of log-transformed marker values was used to produce log multiples of the median (MoM) values for PAPP-A and free β-hCG. The models included terms for the center attended and the machine used for biochemical analysis, gestational age, maternal racial origin, maternal weight, smoking status and method of conception. Bivariate Gaussian distributions were fitted to log MoM PAPP-A and log MoM free β-hCG in trisomy 21 and in unaffected pregnancies. In each case the patient-specific risk for trisomy 21 was estimated by multiplying the individual maternal age-related risk with the likelihood ratio (LR) for fetal nuchal translucency (NT) according to the mixture model and the combined LR for maternal serum free β-hCG and PAPP-A. Estimates of detection rates for trisomy 21 and false-positive rates were calculated for combined screening with measurements of NT at 12 weeks together with measurements of free β-hCG and PAPP-A from 8 to 13 weeks.
In trisomy 21 pregnancies the mean log MoM free β-hCG increased linearly with gestation between 7 and 14 weeks, whereas the relation between log MoM PAPP-A and gestation was fitted by a quadratic equation such that the maximum separation between trisomy 21 and unaffected pregnancies occurs at 9-10 weeks. At a false-positive rate of 3% the detection rate of combined screening at 12 weeks was 86% and this increased to 90% by biochemical testing at 9 weeks and ultrasound scanning at 12 weeks. The detection rate increased to 92% by measuring PAPP-A at 9 weeks and free β-hCG at the time of the scan at 12 weeks.
The performance of first-trimester biochemical screening for trisomy 21 is best at 9-10 weeks rather than at 7-8 or 11-14 weeks.
Ultrasound in Obstetrics and Gynecology 10/2010; 36(4):404-11. · 3.01 Impact Factor
