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Fetal Size in Early Pregnancy


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.

International standards for early fetal size and pregnancy dating based on ultrasound measurement of crown-rump length in the first trimester of pregnancy. Papageorghiou AT, Kennedy SH, Salomon LJ, Ohuma EO, Cheikh Ismail L, Barros FC et al.  Ultrasound Obstet Gynecol 2014, 44(6):641-48.

Tables & Graphs

The crown-rump length (CRL) graphs and charts are available with centiles or Z-scores (Standard deviation).

Calculators & Apps

The “International Fetal Size in Early Pregnancy” Calculator is an Excel-based application. This is a beta version calculator to estimate fetal size between 8+2 and 15+0 weeks’ gestation based on gestational age and crown-rump length measurement. Centiles and z-scores of large datasets can also be calculated.