Use of focus point for plane acquisition to improve reproducibility in fetal biometry.

OBJECTIVE: To assess the reproducibility of ultrasound measurements of fetal biometry using a 'focus point' to assist the acquisition of the relevant plane. METHODS: This was a study of 80 women with a singleton non-anomalous pregnancy who attended University College London Hospital, London, UK, between 18 and 37 weeks' gestation. Planes to measure head circumference (HC), abdominal circumference (AC) and femur length (FL) were obtained four times by two different sonographers with different levels of experience, who were blinded to one another; the first set of images was obtained with reference to a standard image, and the second set of images was obtained using the focus point technique. The focus point was defined as a unique fetal anatomical landmark in each plane (cavum septi pellucidi for HC, two-thirds of the umbilical vein for AC and one of the two extremities of the diaphysis for FL). Once identified, the focus point was maintained in view while the sonographer rotated the probe along three axes (x, y, z) to acquire the relevant plane. Sonographers were either in training or had > 3000 scans worth of experience. Intra- and interobserver reproducibility were assessed using Bland-Altman plots, and absolute values and percentages for mean difference and 95% limits of agreement (LoA) were reported. RESULTS: Overall reproducibility was good, with all 95% LoA < 8%. Reproducibility was improved by use of the focus point compared with the standard technique for both intraobserver comparison (95% LoA, < 4% vs < 6%) and interobserver comparison (95% LoA, < 7% vs < 8%). These findings were independent of sonographer seniority and plane acquired. CONCLUSIONS: Reproducibility of fetal biometry assessment is improved with use of the focus point for plane acquisition, regardless of sonographer experience. We propose that this method should be implemented in clinical practice and training programs in fetal biometry. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Natural history of endometriosis in pregnancy: ultrasound study of morphology of deep endometriosis and ovarian endometrioma.

OBJECTIVE: To assess the morphological appearance of deep endometriosis and ovarian endometrioma in pregnancy using pelvic ultrasound examination. METHODS: This was a prospective observational cohort study conducted over 3 years at University College London Hospital, which is a tertiary level referral unit for early pregnancy complications and an accredited endometriosis center. All women who participated provided written consent and were invited for surveillance ultrasound examination at the time of their routine scans in pregnancy. All scans were performed by a single operator to eliminate interobserver variability. The change in size of ovarian endometrioma and nodules was reported as change in their mean diameter. Ovarian endometrioma with irregular thick inner walls, hyperechoic papillary projections and/or high vascularity and hyperechoic nodules with moderate to high vascularity were reported as decidualized. RESULTS: Sixty-five women with a live, normally sited pregnancy and concomitant ultrasound features of deep and/or ovarian endometriosis were included in the study. The median age of the study population was 34 (range, 23-44) years, and the median gestational age at presentation was 7 + 6 (range, 3 + 6 to 18 + 0) weeks. From the cohort, 47/65 (72%) were nulliparous, 48/65 (74%) had a previous diagnosis of endometriosis and 19/65 (29%) conceived via in-vitro fertilization. There were 10/65 (15% (95% CI, 7-24%)) women with ovarian endometrioma alone, 28/65 (43% (95% CI, 31-55%)) with endometriotic nodules alone and the remaining 27/65 (42% (95% CI, 30-54%)) had both. Of the women with ovarian endometrioma who underwent follow-up, 29/34 (85% (95% CI, 73-97%)) experienced cyst regression, 2/34 (6% (95% CI, 0-14%)) experienced cyst growth, and in 3/34 (9% (95% CI, 0.0-18%)) women, cyst size was unchanged. In 10/34 (29% (95% CI, 14-45%)), there was complete resolution of all cysts. Of the women with nodules who underwent follow-up, 43/51 (84% (95% CI, 74-94%)) experienced nodule regression, 2/51 (4% (95% CI, 0-9%)) experienced nodule growth and, in 6/51 (12% (95% CI, 3-21%)) women, nodule size was unchanged. In 4/51 (8% (95% CI, 0-15%)) women, there was complete resolution of all nodules. In 5/37 (14% (95% CI, 3-25%)) women who attended postnatal follow-up, complete resolution of all endometriotic lesions occurred during pregnancy. In 10/34 (29% (95% CI, 14-45%)) women with ovarian endometrioma and 27/51 (53% (95% CI, 39-67%)) women with nodules, a pattern of growth was observed in the first and second trimesters, followed by regression later in pregnancy. Features of decidualization were observed in 17/34 (50% (95% CI, 33-67%)) women with ovarian endometrioma, most commonly in the first trimester, and in 25/51 (49% (95% CI, 35-63%)) women with nodules, most commonly in the second trimester. CONCLUSIONS: For the majority of women, despite features of decidualization being common in the first and second trimesters, ovarian endometrioma and deep nodules regress during pregnancy. Morphological changes of endometriosis in pregnancy are difficult to differentiate from characteristics of malignant lesions. Better understanding of the appearance of endometriosis in pregnancy is vital to minimize intervention and help counsel women regarding their condition. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Management of late-onset fetal growth restriction: pragmatic approach.

OBJECTIVES: There is limited prospective evidence to guide the management of late-onset fetal growth restriction (FGR) and its differentiation from small-for-gestational age. The aim of this study was to assess prospectively a novel protocol in which ultrasound criteria were used to classify women with suspected late FGR into two groups: those at low risk, who were managed expectantly until the anticipated date of delivery, and those at high risk, who were delivered soon after 37 weeks of gestation. We also compared the outcome of this prospective cohort with that of a historical cohort of women presenting similarly with suspected late FGR, in order to evaluate the impact of the new protocol. METHODS: This was a prospective study of women with a non-anomalous singleton pregnancy at ≥ 32 weeks' gestation attending a tertiary hospital in London, UK, between February 2018 and September 2019, with estimated fetal weight (EFW) ≤ 10th centile, or EFW > 10th centile in addition to a decrease in fetal abdominal circumference of ≥ 50 centiles compared with a previous scan, umbilical artery Doppler pulsatility index > 95th centile or cerebroplacental ratio < 5th centile. Women were classified as low or high risk based on ultrasound and Doppler criteria. Women in the low-risk group were delivered by 41 weeks of gestation, unless they subsequently met high-risk criteria, whereas women in the high-risk group (EFW < 3rd centile, umbilical artery Doppler pulsatility index > 95th centile or EFW between 3rd and 10th centiles (inclusive) with abdominal circumference drop or abnormal Dopplers) were delivered at or soon after 37 weeks. The primary outcome was adverse neonatal outcome and included hypothermia, hypoglycemia, neonatal unit admission, jaundice requiring treatment, suspected infection, feeding difficulties, 1-min Apgar score < 7, hospital readmission and any severe adverse neonatal outcome (perinatal death, resuscitation using inotropes or mechanical ventilation, 5-min Apgar score < 7, metabolic acidosis, sepsis, and cerebral, cardiac or respiratory morbidity). Secondary outcomes were adverse maternal outcome (operative delivery for abnormal fetal heart rate) and severe adverse neonatal outcome. Women managed according to the new protocol were compared with a historical cohort of 323 women delivered prior to the implementation of the new protocol, for whom management was guided by individual clinician expertise. RESULTS: Over 18 months, 321 women were recruited to the prospective cohort, of whom 156 were classified as low risk and 165 were high risk. Adverse neonatal outcome was significantly less common in the low-risk compared with the high-risk group (45% vs 58%; adjusted odds ratio (aOR), 0.6 (95% CI, 0.4-0.9); P = 0.022). There was no significant difference in the rate of adverse maternal outcome (18% vs 24%; aOR, 0.7 (95% CI, 0.4-1.2); P = 0.142) or severe adverse neonatal outcome (3.8% vs 8.5%; aOR, 0.5 (95% CI, 0.2-1.3); P = 0.153) between the low- and high-risk groups. Compared with women in the historical cohort classified retrospectively as low risk, low-risk women managed under the new protocol had a lower rate of adverse neonatal outcome (45% vs 58%; aOR, 0.6 (95% CI, 0.4-0.9); P = 0.026). CONCLUSIONS: Appropriate risk stratification to guide management of late FGR was associated with a reduced rate of adverse neonatal outcome in low-risk pregnancies. In clinical practice, a policy of expectantly managing women with a low-risk late-onset FGR pregnancy at term could improve neonatal and long-term development. Randomized controlled trials are needed to assess the effect of an evidence-based conservative management protocol for late FGR on perinatal morbidity and mortality and long-term neurodevelopment. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Reproducibility of assessment of full-dilatation Cesarean section scar in women undergoing second-trimester screening for preterm birth.

OBJECTIVE: To assess the reproducibility of a standardized method of measuring the Cesarean section (CS) scar, CS scar niche and their position relative to the internal os of the uterine cervix by transvaginal ultrasound in pregnant women with a previous full-dilatation CS. METHODS: This was a prospective, single-center reproducibility study on women with a singleton pregnancy and a previous full-dilatation CS who underwent transvaginal ultrasound assessment of cervical length and CS scar characteristics at 14-24 weeks' gestation. The CS scar was identified as a hypoechogenic linear discontinuity of the myometrium at the anterior wall of the lower uterine segment or cervix. The CS scar niche was identified as an indentation at the site of the scar with a depth of at least 2 mm. The CS scar position was evaluated by measuring the distance to the internal cervical os. CS scar niche parameters, including its length, depth, width, and residual and adjacent myometrial thickness, were assessed in the sagittal and transverse planes. Qualitative reproducibility was assessed by agreement regarding visibility of the CS scar and niche. Quantitative reproducibility of CS scar measurements was assessed using three sets of images: (1) real-time two-dimensional (2D) images (real-time acquisition and caliper placement on 2D images by two operators), (2) offline 2D still images (offline caliper placement by two operators on stored 2D images acquired by one operator) and (3) three-dimensional (3D) volume images (volume manipulation and caliper placement on 2D images extracted by two operators). Agreement on CS scar visibility and the presence of a niche was analyzed using kappa coefficients. Intraobserver and interobserver reproducibility of quantitative measurements was assessed using Bland-Altman plots. RESULTS: To achieve the desired statistical power, 72 women were recruited. The CS scar was visualized in > 80% of images. Interobserver agreement for scar visualization and presence of a niche in real-time 2D images was excellent (kappa coefficients of 0.84 and 0.85, respectively). Overall, reproducibility was higher for real-time 2D and offline 2D still images than for 3D volume images. The 95% limits of agreement (LOA) for intraobserver reproducibility were between ± 1.1 and ± 3.6 mm for all sets of images; the 95% LOA for interobserver reproducibility were between ± 2.0 and ± 6.3 mm. Measurement of the distance from the CS scar to the internal cervical os was the most reproducible 2D measurement (intraobserver and interobserver 95% LOA within ± 1.6 and ± 2.7 mm, respectively). Overall, niche measurements were the least reproducible measurements (intraobserver 95% LOA between ± 1.6 and ± 3.6 mm; interobserver 95% LOA between ± 3.1 and ± 6.3 mm). There was no consistent difference between measurements obtained by reacquisition of 2D images (planes obtained twice and caliper placed), caliper placement on 2D stored images or volume manipulation (planes obtained twice and caliper placed). CONCLUSIONS: The CS scar position and scar niche in pregnant women with a previous full-dilatation CS can be assessed in the second trimester of a subsequent pregnancy using either 2D or 3D volume ultrasound imaging with a high level of reproducibility. Overall, the most reproducible CS scar parameter is the distance from the CS scar to the internal cervical os. The method proposed in this study should enable clinicians to assess the CS scar reliably and may help predict pregnancy outcome. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Isolated single umbilical artery and fetal karyotype.

OBJECTIVE: To determine the need for fetal karyotyping in cases of an isolated single umbilical artery (SUA) identified during the second-trimester routine anomaly scan. METHODS: All patients booked for antenatal care and delivery in our hospital are offered two ultrasound scans in pregnancy, one at 11-13 weeks' gestation as part of screening for chromosomal defects and another at 20-23 weeks for detailed fetal examination. In addition we examine patients referred from other hospitals because of suspected fetal abnormalities during their routine second-trimester scan. We performed a search of the database to retrieve all cases with an SUA and reviewed the ultrasound findings, fetal karyotype and pregnancy outcome. RESULTS: There were 643 cases with SUA, including 424 (65.9%) where the condition was isolated, 133 (20.7%) with one major fetal defect and 86 (13.4%) with multiple defects. The incidence of chromosomal abnormalities was 0% in the isolated SUA group, 3.7% in those with one defect and 50.7% in those with multiple defects. The commonest chromosomal abnormalities were trisomy 18, trisomy 13 and triploidy, which together accounted for 82.9% of cases. CONCLUSION: The finding of an SUA should prompt the sonographer to search for fetal defects and if these are found the risk for chromosomal abnormalities is increased. In cases of apparently isolated SUA there is no evidence of increased risk of chromosomal abnormalities.

Inhibin, activin, follistatin, activin receptors and beta-glycan gene expression in the placental tissue of patients with pre-eclampsia.

The objective of this study was to quantify the relative expression of inhibin alpha, inhibin/activin beta(A), beta(B), beta(C), follistatin, activin receptors and beta-glycan genes in placental tissue of term pre-eclamptic patients and controls to investigate if these genes are up-regulated in the placenta in pre-eclampsia. Seven women with pre-eclampsia symptoms were matched with 10 normal pregnant controls for gestational age, maternal age, and parity. Total RNA was isolated from each sample. Complementary DNA samples produced by reverse transcription were used in the real time PCR to quantify the expression of inhibin alpha subunit, inhibin/activin beta(A), beta(B), beta(C) subunits, follistatin, ACTRIA, ACTRIB, ACTRIIA, ACTRIIB, beta-glycan and GAPDH genes. The ratio between the target and GAPDH expression was calculated to provide relative gene expression. Inhibin alpha:GAPDH and inhibin/activin beta(A): GAPDH ratios were significantly higher in placental tissue from women with pre-eclampsia (P = 0.04 and P = 0.01 respectively) compared with matched control placental gene expression. Placental samples from both groups expressed beta(B), beta(C), follistatin, activin receptors and beta-glycan genes. However, there was no significant difference in the relative expression of these genes between the groups. Increases in the placental expression of inhibin alpha and inhibin/activin beta(A) subunit genes could contribute to the rise in circulating levels of inhibin A and activin A in pre-eclampsia. The mechanism(s) involved in increased gene expression in pre-eclampsia is as yet unclear.