First trimester ultrasound in the age of cell-free DNA screening: What are we missing?

Abstract

To evaluate the utility of first trimester (FT) ultrasound (US) between 10 and 14weeks gestation in identifying fetal findings that would impact clinical management. We performed a retrospective review of FT US associated with an abnormal ICD-10 code from August 2016 to December 2018. Results of FT US, genetic testing, and management decisions were abstracted from the electronic health record. A total of 20,594 FT US were performed within our study period, representing 6064 unique patients. Of these, 278 ultrasounds were noted to have fetal findings (278/6064, 4.6%). The most frequent fetal findings were fetal demises (98/278, 35.3%), followed by increased NT/cystic hygroma (67/278, 24.1%), and multiple anomalies (35/278, 12.6%). There was a significant difference between the frequency of fetal findings between patients considered advanced maternal age (AMA) and those who were not (p=0.017). However, there was no significant difference in the frequency of specific anomalies between these two groups (p=0.103). FT US provides clinical information outside the scope of cfDNA screening in both AMA and non-AMA populations regarding viability and fetal anatomy. Earlier detection of these findings is crucial to allow for the opportunity of informed discussion of testing strategy and decision making.