Section Ossification centres around elbow 6 Nov 2021 AnatomyAge (years) of appearance of ossification centre on radiographAge (years) of fusionCapitellum0-213-16Radial head3-613-17Medial epicondyle3-9up to 20Trochlea7-1313-16Olecranon 8-1013-16Lateral epicondyle8-1213-16'CRITOE'
Section Fetal weight percentiles – third trimester 19 Aug 20167 Sep 2021 Doubilet, Peter M., et al. "Improved birth weight table for neonates developed from gestations dated by early ultrasonography." Journal of ultrasound in medicine 16.4 (1997): 241-249.
Section Crown rump length – gestational age 19 Aug 20167 Sep 2021 Robinson, H. P., and J. E. E. Fleming. "A critical evaluation of sonar “crown‐rump length” measurements." BJOG: An International Journal of Obstetrics & Gynaecology 82.9 (1975): 702-710.
Section Mean sac diameter and gestational age 19 Aug 20167 Sep 2021 These measurements are taken in transvaginal scan. Daya, S. A. L. I. M., et al. "Early pregnancy assessment with transvaginal ultrasound scanning." CMAJ: Canadian Medical Association Journal 144.4 (1991): 441.
Section Abdominal circumference – fetal biometry 19 Jul 20167 Sep 2021 Kurmanavicius, Juozas, et al. "Fetal ultrasound biometry: 2. Abdomen and femur length reference values." BJOG: An International Journal of Obstetrics & Gynaecology 106.2 (1999): 136-143.
Section Head circumference – fetal biometry 19 Jul 20167 Sep 2021 Kurmanavicius, Juozas, et al. "Fetal ultrasound biometry: 2. Abdomen and femur length reference values." BJOG: An International Journal of Obstetrics & Gynaecology 106.2 (1999): 136-143.