Adverse pregnancy outcome in fetuses with early increased nuchal translucency: prospective cohort study.

OBJECTIVES: An increased nuchal translucency (NT) thickness of ≥ 3.5 mm is a well-established marker for congenital anomalies and adverse pregnancy outcome between 11 and 14 weeks' gestation, but little is known about its performance as a screening tool before 11 weeks. We aimed to investigate, in a prospective setting, whether fetuses with increased NT before 11 weeks are at risk for adverse pregnancy outcome. METHODS: This was a prospective cohort study including pregnant women with a viable fetus with NT ≥ 2.5 mm and a crown-rump length (CRL) < 45 mm. All included women were referred to our fetal medicine unit (FMU) and scheduled for a follow-up scan where the NT was remeasured after 1 week when the CRL was > 45 mm. Two groups were evaluated: cases with a normalized NT (< 3.5 mm) and cases with persistently increased NT (≥ 3.5 mm). The cases were monitored until 4 weeks after delivery. The main outcome was a composite adverse outcome of aneuploidy, other genetic disorders, structural anomalies and pregnancy loss. We performed subgroup analyses of NT thickness at inclusion and normalized or persistently increased NT at follow-up. RESULTS: The study included 109 cases, of which 39 (35.8%) had an adverse pregnancy outcome. Of these, 64.1% (25/39) were aneuploid, corresponding to 22.9% (25/109) of the total study population. In the subgroups of NT thickness at inclusion of 2.5-3.4 mm, 3.5-4.4 mm and ≥ 4.5 mm, an adverse outcome was reported in 22.0% (9/41), 40.0% (18/45) and 52.2% (12/23), respectively. In fetuses with a normalized NT and without ultrasound abnormalities at the follow-up scan, the incidence of adverse outcome was 8.5% (5/59), of which 5.1% (3/59) cases were aneuploid. CONCLUSIONS: Fetuses with an early increased NT thickness are at considerable risk of an adverse pregnancy outcome, even if the NT normalizes after 11 weeks. Not all congenital anomalies can be diagnosed with routine first-trimester screening, such as non-invasive prenatal testing and/or a first-trimester anomaly scan. Therefore, expectant parents should always be referred to a FMU for detailed ultrasonography. Invasive prenatal testing should be offered if an increased NT of ≥ 2.5 mm is observed before 11 weeks' gestation. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Resultado adverso del embarazo en fetos con aumento precoz de la translucencia nucal: estudio prospectivo de cohortes OBJETIVOS: El aumento del grosor de la translucencia nucal (TN) de ≥3,5 mm es un marcador bien establecido de anomalías congénitas y resultados adversos del embarazo entre las semanas 11 y 14 de gestación, pero se sabe poco sobre su rendimiento como herramienta de cribado antes de las 11 semanas. El objetivo fue investigar, en un contexto prospectivo, si los fetos con aumento de la TN antes de las 11 semanas corren riesgo de presentar resultados adversos del embarazo. MÉTODOS: Se trató de un estudio prospectivo de cohortes que incluyó a embarazadas con un feto viable con una TN ≥2,5 mm y una longitud céfalo­caudal (LCC) <45 mm. Todas las mujeres incluidas fueron remitidas a una unidad de medicina fetal (UMF) y con cita para una prueba de seguimiento en la que se volvió a medir la TN al cabo de 1 semana cuando la LCC era >45 mm. Se evaluaron dos grupos: casos con una TN normalizada (<3.5 mm) y casos con una TN persistentemente aumentada (≥3,5 mm). A los casos se les dio seguimiento hasta 4 semanas después del parto. El resultado principal fue un resultado adverso compuesto de aneuploidía, otros trastornos genéticos, anomalías estructurales y pérdida del embarazo. Se realizaron análisis de subgrupos del grosor de la TN en el momento de la inclusión y de la TN normalizada o persistentemente aumentada en el seguimiento. RESULTADOS: El estudio incluyó 109 casos, de los cuales 39 (35,8%) tuvieron un resultado adverso del embarazo. De ellos, el 64,1% (25/39) eran aneuploides, lo que supone el 22,9% (25/109) de la población total del estudio. En los subgrupos de grosor de la TN en el momento de la inclusión de 2,5­3,4 mm, 3,5­4,4 mm y ≥4,5 mm, se notificó un resultado adverso en el 22,0% (9/41), el 40,0% (18/45) y el 52,2% (12/23), respectivamente. En los fetos con una TN normalizada y sin anomalías ecográficas en la ecografía de seguimiento, la incidencia de resultados adversos fue del 8,5% (5/59), de los cuales el 5,1% (3/59) de los casos eran aneuploides. CONCLUSIONES: Los fetos con un aumento precoz del grosor de la TN corren un riesgo considerable de sufrir un resultado adverso del embarazo, incluso si la TN se normaliza después de 11 semanas. No todas las anomalías congénitas pueden diagnosticarse con un cribado rutinario en el primer trimestre, como las pruebas prenatales no invasivas y/o una ecografía de anomalías en el primer trimestre. Por lo tanto, los futuros padres siempre deben ser remitidos a una UMF para una ecografía detallada. Se debería ofrecer una prueba prenatal invasiva si se observa un aumento de la TN de ≥2,5 mm antes de las 11 semanas de gestación.

Fetal premature atrial contractions: natural course, risk factors and adverse outcomes.

OBJECTIVE: Fetal premature atrial contractions (PACs) are usually benign, but are associated with congenital heart defects (CHDs) and tachyarrhythmias, which in turn carry a risk of cardiac failure and fetal death. We aimed to explore the frequency of adverse outcomes and to identify risk factors for tachyarrhythmias in pregnancies complicated by fetal PACs. METHODS: Fetuses diagnosed with PACs at two academic centres in Amsterdam between 2007 and 2022 were included in this retrospective cohort study. Cases with congenital anomalies or a prior diagnosis of CHD or other arrhythmias were excluded. M-mode and Doppler tracings were reanalysed and the PACs frequency recorded. We explored the incidence of adverse outcomes defined as: underlying CHDs not identified during the 20 weeks fetal anomaly scan, tachyarrhythmias, other arrhythmias, administration of antiarrhythmic therapy and death. Risk factors for tachyarrhythmias were analysed using odds ratios (OR). RESULTS: In 24% of the referred cases, PACs resolved before confirmation at the fetal medicine unit (FMU). Of the 939 included cases with proven PACs, the total incidence of adverse outcome was 6.8% (64/939). CHDs were diagnosed in 14 cases (1.5%, 95%-CI 0.9-2.5%) of which eight prenatally and six postnatally. Compared to baseline, the incidence of CHD in the presence of fetal PACs was increased (OR 1.8, 95%-CI 1.0-3.3, p=0.034). Tachyarrhythmias occurred prenatally and/or postnatally in 32 cases (3.4%) of which eight (25.0%) showed signs of cardiac failure and in 23 (71.9%) antiarrhythmic therapy was required. None of the tachyarrhythmias led to fetal or neonatal death. Risk factors for a tachyarrhythmia were: PACs with short runs of supraventricular tachycardia (OR 99), blocked PACs (OR 30), PACs in bigeminy (OR 22), frequent PACs (1 per 5-10 beats) (OR 6.9), signs of cardiac failure (OR 14) and the presence of a foramen ovale aneurysm (OR 5.0). CONCLUSIONS: PACs are generally benign and resolve often spontaneously. However, fetuses with irregular heart rate should be referred for advanced ultrasonography, which should focus on the type of PACs and risk classification. When risk factors for tachyarrhythmias are identified, weekly heart rate monitoring is advised until the PACs resolve. In the absence of risk factors, standard obstetric care may be sufficient with additional instructions to report reduced fetal movements. Should tachyarrhythmias or cardiac failure develop, referral back to the FMU is then indicated. This article is protected by copyright. All rights reserved.

Implications of fetal premature atrial contractions: systematic review.

OBJECTIVE: Fetal heart-rate irregularities occur in 1-2% of pregnancies and are usually caused by premature atrial contractions (PAC). Although PAC are considered benign, they may be associated with cardiac defects and tachyarrhythmia. We aimed to determine the incidence of congenital heart defects (CHDs) and complications in fetuses with PAC. METHODS: This was a systematic review and meta-analysis conducted in accordance with the PRISMA statement for reporting items for systematic reviews and meta-analyses. MEDLINE and EMBASE were searched from 1990 to June 2021 to identify studies on fetuses with PAC. The primary outcome was CHD; secondary outcomes were complications using the endpoints supraventricular tachyarrhythmia (SVT), cardiac failure and intrauterine fetal demise. Meta-analysis of proportions was performed, subdivided into high-risk and low-risk populations based on reason for referral. Pooled incidences with 95% CIs were calculated. RESULTS: Of 2443 unique articles identified, 19 cohort studies including 2260 fetuses were included. The pooled incidence of CHD in fetuses with PAC was 2.8% (95% CI, 1.5-4.1%), when 0.6% is the incidence expected in the general population. The pooled incidence of CHD was 7.2% (95% CI, 3.5-10.9%) in the high-risk population and 0.9% (95% CI, 0.0-2.0%) in the low-risk population. SVT occurred in 1.4% (95% CI, 0.6-3.4%) of fetuses diagnosed with PAC. Cardiac failure was described in 16 fetuses (1.4% (95% CI, 0.5-3.5%)), of which eight were CHD-related. Intrauterine fetal demise occurred in four fetuses (0.9% (95% CI, 0.5-1.7%)) and was related to CHD in two cases. CONCLUSIONS: Our findings suggest that the risk of CHD in fetuses with PAC is 4-5 times higher than that in the general population. CHD was present more frequently in the high-risk population. Consequently, an advanced ultrasound examination to diagnose PAC correctly and exclude CHD is recommended. Complications of PAC are rare but can result in fetal demise, thus weekly fetal heart-rate monitoring remains advisable to enable early detection of SVT and to prevent cardiac failure. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.