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Pregnancy Dating


Pregnancy dating by fetal crown-rump length: a systematic review of charts: Napolitano R, Dhami J, Ohuma EO, Ioannou C, Conde-Agudelo A, Kennedy SH et al. BJOG 2014, 121(5):556-5.

Ultrasound based gestational age estimation in late pregnancy. Papageorghiou AT, Kemp B, Stones W, Ohuma EO, Kennedy SH, Purwar M et al.  Ultrasound Obstet Gynecol 2016. 48(6):719-26 

Tables & Graphs

Crown-rump length dating in early pregnancy

Calculators & Apps

The “International Gestational Age Assessment” Calculator is an Excel-based application. This is a beta version calculator for gestational age based on fetal measurements (crown-rump length; or head circumference and femur length). Centiles and z-scores of large datasets can also be calculated.