First trimester examination of fetal anatomy: clinical practice guideline by the World Association of Perinatal Medicine (WAPM) and the Perinatal Medicine Foundation (PMF)

First-Trimester Ultrasound Screening in Routine Obstetric Practice

Technologic advances and ultrasonographer-physician experience in fetal imaging have led to significant improvements in our ability to distinguish between normal and abnormal fetal structural development in the latter part of the first trimester. As a critical component of pregnancy care, assessment of fetal anatomy at the end of the first trimester with a standardized imaging protocol should be offered to all pregnant patients regardless of aneuploidy screening results because it has been demonstrated to identify approximately half of fetal structural malformations. Early identification of abnormalities allows focused genetic counseling, timely diagnostic testing, and subspecialist consultation. In addition, a normal ultrasound examination result offers some degree of reassurance to most patients. Use of cell-free DNA alone for aneuploidy screening while foregoing an accompanying early anatomic evaluation of the fetus will result in many anomalies that are typically detected in the first trimester not being identified until later in pregnancy, thus potentially diminishing the quality of obstetric care for pregnant individuals and possibly limiting their reproductive options, including pregnancy termination.

Diagnosis of single umbilical artery and risk of foetal congenital malformations by prenatal ultrasound: a retrospective study

BACKGROUND

Single umbilical artery (SUA) is strongly associated with foetal structural abnormalities; however, the exact pattern of this association has not been described. We aimed to investigate the occurrence of malformations in singleton pregnancies with SUA in China and to study the association between the absent side of the umbilical artery and foetal malformations.

METHODS

This was a retrospective study of singleton pregnancies for which routine first-trimester anatomical screening was performed at 11+ 0-13+ 6 gestational weeks and, if the pregnancy continued, a second-trimester scan was performed at 20+ 0-24+ 0 weeks. Data were extracted from records at the referral centre, the Obstetrics and Gynecology Hospital of Fudan University, between January 2011 and April 2019 (n = 47,894). Using logistic regression, the odds ratios (OR) with 95% confidence intervals (CIs) were calculated for malformations associated with SUA.

RESULTS

The incidence of SUA in our study was 2.0% (970/47,894). Of all foetuses with SUA, 387 (39.9%) had structural malformations. The malformation type varied, with cardiovascular complications being the most common. A robust association was observed between SUA and oesophageal stenosis or atresia (OR: 25.33), followed by cardiovascular (OR: 9.98-24.02), scoliosis (OR: 18.62), genitourinary (OR: 2.45-15.66), and brain malformations (OR: 4.73-9.12). The absence of the left umbilical artery (n = 445, 45.9%) was consistent with that of the right umbilical artery (n = 431, 44.4%). Furthermore, a significantly higher rate of an absent right than the left umbilical artery (p<0.01) was observed in SUA with foetal abnormalities than in SUA with no malformations.

CONCLUSIONS

Overall, we observed a higher risk of various specific malformations in foetuses with SUA, and a strong association between SUA and oesophageal stenosis or atresia. The absence of the right umbilical artery was most common in foetuses with SUA and structural malformations. This study provides a reference for ultrasonographers in conducting foetal structural screening for pregnant women with SUA.

Clinical Practice Guidelines and Recommendations by the World Association of Perinatal Medicine and Perinatal Medicine Foundation: Reporting Suspected Findings from Fetal Central Nervous System Examination

These guidelines follow the mission of the World Association of Perinatal Medicine, in collaboration with the Perinatal Medicine Foundation, which brings together groups and individuals worldwide, with the aim to improve prenatal detection of central nervous system anomalies and the appropriate referral of pregnancies with suspected fetal anomalies. In addition, this document provides further guidance for healthcare practitioners with the goal of standardizing the description of ultrasonographic abnormal findings.

Cleft Lip and Cleft Palate: Time to Include Orofacial Ultrasound Markers Into the First-Trimester Anatomy Scan?

Orofacial clefts are one of the most common congenital malformations. The prenatal diagnosis is often made in the second trimester of pregnancy as result of ultrasound examination of the midface on coronal and axial planes. However, the diagnosis in the first trimester is elusive due to the small size of the facial structures and technical limitations present at this early gestational age. In this Commentary, we suggest the routine systematic ultrasound identification of easy-to-obtain landmarks to improve the detection of cleft lip and cleft palate in the first trimester. These include, but are not limited to, visualization of the primary palate using the coronal plane of the face looking for disruption at the base of the retronasal triangle, and visualization of the palate using the sagittal plane looking for the maxillary gap and loss of the superimposed line. Early prenatal detection of orofacial clefts would allow a more detailed search for associated chromosomal anomalies or genetic syndromes.