Literature:
ACOG PB 175 Ultrasound in Pregnancy 2016
ACOG PB 43 Fetal growth restriction 2021
NEJM 2013 - Diagnostic Criteria Pregnancy Loss (US images)
Other useful links:
Creogs over coffee -- OB US Jan 2020
ACOG Position Statement: Qualifications for Performing and Interpreting Imaging Procedures in Obstetrics and Gynecology 2023