A practical method for prenatal diagnosis of anal atresia by second trimester ultrasound screening - A retrospective study.

OBJECTIVES: The study aimed to demonstrate the performance of anal atresia ultrasound screening in the second trimester and to describe associated experiences in a primary care fetal medicine clinic. MATERIALS AND METHODS: We retrospectively analyzed the medical records of fetuses who underwent a second-trimester screening at the Taiji clinic between November 2019 and May 2022. Fisher's exact test was conducted to investigate potential risk factors. RESULTS: There were 28 459 fetuses screened in our clinic during the study period; eventually, 6 cases were diagnosed with anal atresia after birth. The incidence of anal atresia in our sample was 2.11 in 10 000. Based on our findings, potential risk factors significantly associated with anal atresia included: multiple pregnancies (p-value = 0.0185) and in-vitro fertilization (p-value = 0.038). Half of the anal atresia cases were associated with abnormalities affecting other organ systems, most frequently the genitourinary system (66.7%) and cardiovascular system (66.7%), especially persistent left superior vena cava (2 cases). CONCLUSION: Anal atresia is a malformation that requires extensive care; the clinical management after the prenatal discovery of its signs should include testing for chromosomal abnormalities and close monitoring of the amniotic fluid volume. Therefore, prenatal ultrasound screening for anal atresia in the second trimester is critical, particularly in the cases of multiple and IVF pregnancies, and multiple abnormalities. The fetuses with ultrasound signs of anal atresia should be followed at a later gestational period and referred to a specialized institution for postnatal management planning and parental counseling.

Ultrasonographic cervical length screening at 20-24 weeks of gestation in twin pregnancies for prediction of spontaneous preterm birth: A 10-year Taiwanese cohort.

BACKGROUND: Shortened cervical length is one of the primary predictors for spontaneous preterm deliveries in twin pregnancies. However, there is lack of consensus regarding cut-off values. Recent evidence highlights that established cut-offs for cervical length screening might not always apply across different populations. This study aims to present the distribution of cervical length in Taiwanese twin pregnancies and to assess its predictive value for spontaneous preterm birth during mid-trimester screening. MATERIALS AND METHODS: This retrospective analysis of cervical length screening in Taiwan evaluated 469 twin pregnancies between 20-24 weeks of gestation. Outcome data were obtained directly from the medical records of the delivery hospital. The study explored the predictive value of cervical length screening for spontaneous preterm birth and the characteristics of cervical length distribution in Taiwanese twin pregnancies. RESULTS: The average gestational age at screening was 22.7 weeks. Cervical length values displayed a non-normal distribution (p-value <0.001). The median, 5th and 95th centiles were 37.5 mm 25.1 mm, and 47.9 mm, respectively. Various cut-off values were assessed using different methods, yielding positive [negative] likelihood ratios for spontaneous preterm births between 32-37 weeks of gestational age (GA) (1.3-30.1 and [0.51-0.92]) and for very preterm births between 28-32 weeks GA (5.6-51.1 and [0.45-0.64]). CONCLUSIONS: The findings from our analysis of Taiwanese twin pregnancies uphold the moderate predictive potential of cervical length screening, consistent with prior investigations. The presented likelihood ratios for predicting preterm birth at different gestational ages equip clinicians with valuable tools to enhance their diagnostic rationale and resource utilization. By fine-tuning screening parameters according to the spontaneous preterm birth prevalence and clinical priorities of the particular population, healthcare providers can enhance patient care. Our data implies that a cervical length below 20 mm might provide an optimal balance between minimizing false negatives and managing false positives when predicting spontaneous preterm birth.

High-type anal atresia presenting as a pseudo "target sign" on prenatal ultrasound.

OBJECTIVE: We present prenatal ultrasound images of two high anal atresia cases. The main screening tool used in our clinic is the "target sign" in the tangential view of the fetal perineum. In the current report, we discuss some challenges in the existing screening practices. CASE REPORT: CASE 1: A 28-year-old woman (gravida 1, para 0) with a twin pregnancy underwent ultrasound screening at 21 weeks of gestation when an absent "target sign" in twin A was discovered. At the same time, we were able to present evidence that if the wrong plane was visualized, other structures could be mistaken as the "target sign". Eventually, high-type anal atresia was confirmed postnatally in Twin A. CASE 2: A 29-year-old woman (gravida 1, para 0) came to our clinic for routine screening at 23 weeks of gestation. In the standard tangential view at the level of the perineum, a low-high concentric circle structure resembling a "target sign" was visualized during a prenatal scan. However, anal atresia was discovered postnatally. A retrospective review of prenatal images revealed discrepancies from the typical "target sign". CONCLUSION: High-type anal atresia may present as a pseudo "target sign" on prenatal ultrasound. Visualization of a "target sign" on fetal ultrasound does not always exclude the diagnosis of anal atresia. It is crucial to evaluate the size, shape, level, and position of the "target sign". The appearance of the bilateral hyperechoic perianal tissue is a hint for the screening of anal atresia.

Fetal arrhythmias case series: Experiences from a fetal screening center in Taiwan.

OBJECTIVE: Fetal arrhythmias are common and in rare cases can be associated with severe mortality and morbidity. Most existing articles are focused on classification of fetal arrhythmias in referral centers. Our main objective was to analyze types, clinical characteristics, and outcomes for arrhythmia cases in general practice. CASE REPORT: We retrospectively reviewed a case series of fetal arrhythmias in a fetal medicine clinic between September 2017 and August 2021. FETAL ARRHYTHMIAS IN OUR SAMPLE PRESENTED BY: Ectopies (86%, n = 57), bradyarrhythmias (11%, n = 7), and tachyarrhythmias (3%, n = 2). One tachyarrhythmia case was associated with Ebstein's anomaly. Two cases of second-degree AV block received transplacental fluorinated steroid therapy with recovery of fetal cardiac rhythm in later gestation. One case of complete AV block developed hydrops fetalis. CONCLUSION: Detection and careful stratification of fetal arrhythmias in obstetric screening is crucial. While most arrhythmias are benign and self-limited, some require prompt referral and timely intervention.

Congenital radioulnar synostosis: is prenatal diagnosis possible? - A case report.

OBJECTIVES: The main objectives of this case report are to discuss prenatal ultrasound findings of congenital radioulnar synostosis and to review the literature. CASE REPORT: A patient was diagnosed with congenital radioulnar synostosis at eight months old when parents noticed limited motions in the child's left forearm. The parent denied any traumatic or family history of bony malformations. Physical examination by a pediatric orthopedics specialist and digital radiography revealed proximal radioulnar synostosis. The case report includes perinatal course, comparison between the postnatal radiography and fetal ultrasound images. CONCLUSION: Congenital radioulnar synostosis is often associated with sex chromosome abnormalities and congenital musculoskeletal disorders or syndromes affecting limbs. Isolated congenital radioulnar synostosis is hardly diagnosed before birth, in some cases even have been neglected postnatally. Knowing the developmental milestones of the forearm and specified high-risk groups might help develop a targeted screening strategy to increase the possibility of early detection and intervention.

Age-specific effect of fresh versus frozen embryo transfer on fetal anomalies or intrauterine growth restriction rate.

OBJECTIVE: To compare the prevalence of congenital fetal anomalies or intrauterine fetal growth restriction (IUGR) diagnosed prenatally between two in-vitro fertilization (IVF) methods-fresh embryo transfer (ET) and frozen embryo transfer (FET). MATERIALS AND METHODS: We retrospectively reviewed medical records of patients that had conceived via IVF, and had a fetal anatomical scan performed at Taiji Clinic between 2015 and 2019. The prevalence of fetal anomalies or IUGR between both IVF methods were compared. Prevalence of congenital anomalies or IUGR by maternal age and embryo transfer type were compared by means of Chi-square analysis. Using multivariate logistic regression, we investigated factors that might be associated with higher rates of fetal anomalies or IUGR, such as parity and number of embryos transferred. RESULTS: A total of 2441 cases were selected (ET: n = 627 and FET: n = 1814). There was non-significant difference in the prevalence of fetal anomalies or IUGR between ET and FET groups (6.4% vs. 5.5%, p = 0.39). However, among women younger than 34 years of age, prevalence of fetal anomalies or IUGR was significantly higher in ET group (4.6% vs. 9.9%, p = 0.03). CONCLUSIONS: Our findings suggest an age-specific effect of IVF method on the rate of fetal anomalies or IUGR and may provide useful information for physicians and infertile couples to optimize their IVF treatment plans and improve birth outcomes.

Revisions to mid-pregnancy cervical length reference range for preterm birth screening among singleton pregnancies in Taiwan - 10 years' experiences.

OBJECTIVE: Our study aimed to build a normal reference range for routine mid-pregnancy cervical length screening for preterm birth (PTB) based on a large cross-section of Taiwanese singleton pregnancies. Based on our reference range findings, we aim to develop a Z-score and centile calculator. MATERIALS AND METHODS: We performed a retrospective analysis of the routine mid-trimester cervical length measurement in low-risk singleton pregnancies (without known abnormal growth or karyotype, congenital malformation, history of preterm birth due to preterm premature rupture of the membranes, or history of cervical cerclage treatment). From November 2008 to June 2018, the cervical lengths of 51,644 Taiwanese low-risk pregnant women were measured by experienced sonographers via transvaginal ultrasound during second trimester fetal anatomical screening at 20-24 weeks of gestation. Kolmogorov-Smirnov test was used to assess the normality of the distribution. Cole's lambda, mu, sigma (LMS) method was applied to build mid-pregnancy cervical length reference range and calculate Z-scores. Cut-off values of 2.5, 2.0 and 1.5 cm were used to evaluate the number of pregnancies considered high-risk for PTB. RESULTS: Kolmogorov-Smirnov test showed that the cervical length measurements did not follow a normal distribution (<0.001). Reference range constructed by LMS method was presented in our study. Mean cervical length was 3.82 cm (SD = 0.62 cm). Overall, less than 0.3% of women had a cervical length shorter than 1.5 cm. CONCLUSION: We are providing an open access calculator for z-score and centile calculation for use in clinical practice for assessing how CL measurement compares in normally developing singleton pregnancies. Further investigation is needed to determine if Z-scores can better assess risk for PTB compared to fixed cut-offs. Since Z-scores are used to assess large deviations from normal development, they may be a useful tool for risk assessment and can be the basis for future standardized screening protocol in Taiwan.

Prenatal ultrasound diagnosis of neural tube defects in the era of intrauterine repair - Eleven years' experiences.

OBJECTIVE: To modify the current neural tube defect (NTD) classification for fetal medicine specialists, and to investigate the impact of prenatal ultrasound conus medullaris position screening on the detection rate of closed spinal dysraphism and pregnancy outcomes. MATERIALS AND METHODS: The clinical data of 112 patients prenatally diagnosed with neural tube defects in Taiji clinic from 2008 to 2018 were retrospectively analyzed. All cases were classified following the modified classification. We compared the detection rate before and after introducing the conus medullaris screening and pregnancy outcomes for NTD types. RESULTS: Closed spinal dysraphism type prevailed in our sample (43.8%). The median gestational age at the time of detection for cranial dysraphism was 13.3 weeks, open spinal dysraphism was 22.0 weeks, and closed spinal dysraphism was 22.6 weeks. All cranial dysraphism (n = 43) and open spinal dysraphism cases (n = 20) had pregnancies terminated. For closed spinal dysraphism Class 1, the live-birth rate was 100.0% in the cases without other anomalies and 33.3% in the cases with other anomalies, respectively (X2 = 17.25, p < 0.001). Similarly, for Class 2, pregnancy continuation rate was 50.0% in cases without other anomalies and 20.0% in cases with other anomalies, yet it failed to reach statistical significance (X2 = 0.9, p = 0.524). CONCLUSION: Our case series may help to improve early screening and prenatal diagnosis of NTDs. Modified classification is adjusted for use in ultrasound fetal care facilities, which could be used for predicting pregnancy outcome. We suggest promoting first-trimester anatomical screening in order to make an earlier diagnosis and therefore provide better prenatal care for open spinal dysraphism cases in the era of intrauterine repair. Our findings imply that the use of fetal conus medullaris position as a marker for closed spinal dysraphism improves the detection rate and would unlikely lead to a higher termination rate.

Multidisciplinary team approach to the prenatal management of orofacial clefts: a single center cohort study in Taiwan.

Advances in ultrasound fetal diagnostics and treatment have created a dilemma for doctors and parents: choosing whether to continue with a pregnancy as well as choosing between various treatment options. A multidisciplinary approach has been widely accepted in the management of other prenatally diagnosed anomalies and has shown superior results compared to routine care. We present a retrospective cohort of patients prenatally diagnosed with orofacial clefts who were offered consultation by an expert multidisciplinary team, including: a fetal medicine specialist, an obstetrician, a plastic surgeon, and a case managing nurse. We analyzed factors influencing parents' decision to utilize a consultation service, as well as their decision about pregnancy continuation. Our results suggest that the presence of other anomalies and maternal age heavily influenced the decision about the uptake of consultations. If consulted by the team, parents tended to continue with the pregnancy, even when accounting for fetal gender and maternal age. On the other hand, having a consultation had varying effects depending on the cleft type. The findings suggest that multidisciplinary consultations may be an efficient approach in managing pregnancies complicated by orofacial cleft anomalies; which may help in preventing unnecessary pregnancy terminations and developing a sufficient postnatal care plan.