Fetal growth velocity standards from the Fetal Growth Longitudinal Study of the INTERGROWTH-21st Project
Eric O. Ohuma, José Villar, Yuan Feng, Luo Xiao, Laurent Salomon, Fernando C. Barros, Leila Cheikh Ismail, William Stones, Yasmin A. Jaffer, M. Oberto, J. Alison Noble, Michael G. Gravett, Qingqing Wu, César G. Victora, Ann Lambert, Paola Di Nicola, Manorama Purwar, Zulfiqar A Bhutta, Stephen Kennedy, Aris T. Papageorghiou, M. Katz, M. K. Bhan, Cutberto Garza, Shehla Zaidi, Ana Langer, P M Rothwell, Sir D. Weatherall, Zulfiqar A Bhutta, José Villar, Sidney H. Kennedy, David Altman, Fernando C. Barros, Enrico Bertino, F.G. Burton, Mário Henrique Burlacchini de Carvalho, Leila Cheikh Ismail, Wm. Cameron Chumlea, Michael G. Gravett, Yasmin A. Jaffer, Ann Lambert, P. Lumbiganon, J. Alison Noble, Ran Pang, Aris T. Papageorghiou, Manorama Purwar, Juan Á. Rivera, César G. Victora, José Villar, David Altman, Zulfiqar A Bhutta, Leila Cheikh Ismail, Sidney H. Kennedy, Ann Lambert, J. Alison Noble, Aris T. Papageorghiou, José Villar, Sidney H. Kennedy, Leila Cheikh Ismail, Ann Lambert, Aris T. Papageorghiou, M. Shorten, L. Hoch, Hannah Knight, Eric O. Ohuma, Candace M. Cosgrove, I. Blakey, David Altman, Eric O. Ohuma, José Villar, David Altman, Fenella Roseman, N. Kunnawar, Shengjia Gu, J.H. Wang, Mingxing Wu, Marlos Rodrigues Domingues, P. Gilli, L. Juodvirsiene, L. Hoch, N. Musee, H. Al-Jabri, S. Waller, Candace M. Cosgrove, D. Muninzwa, Eric O. Ohuma, D. Yellappan, A. Carter, D. Reade, Raymond Miller, Aris T. Papageorghiou, Laurent Salomon, A. Leston, Andréia Moreira de Souza Mitidieri, F. Al-Aamri, W. Paulsene, Joyce Sande, W.K.S. Al-Zadjali, C. Batiuk, S. Bornemeier, Mário Henrique Burlacchini de Carvalho
Abstract
BACKGROUND: Human growth is susceptible to damage from insults, particularly during periods of rapid growth. Identifying those periods and the normative limits that are compatible with adequate growth and development are the first key steps toward preventing impaired growth. OBJECTIVE: Fetal Growth Standards. STUDY DESIGN: Project with rigorous standardization of all study procedures, equipment, and measurements that were performed by trained ultrasonographers. Gestational age was accurately determined clinically and confirmed by ultrasound measurement of crown-rump length at <14 weeks' gestation. Thereafter, the ultrasonographers, who were masked to the values, measured the fetal head circumference, biparietal diameter, occipitofrontal diameter, abdominal circumference, and femur length in triplicate every 5 weeks (within 1 week either side) using identical ultrasound equipment at each site (4-7 scans per pregnancy). Velocity increments across a range of intervals between measures were modeled using fractional polynomial regression. RESULTS: Peak velocity was observed at a similar gestational age: 16 and 17 weeks' gestation for head circumference (12.2 mm/wk), and 16 weeks' gestation for abdominal circumference (11.8 mm/wk) and femur length (3.2 mm/wk). However, velocity growth slowed down rapidly for head circumference, biparietal diameter, occipitofrontal diameter, and femur length, with an almost linear reduction toward term that was more marked for femur length. Conversely, abdominal circumference velocity remained relatively steady throughout pregnancy. The change in velocity with gestational age was more evident for head circumference, biparietal diameter, occipitofrontal diameter, and femur length than for abdominal circumference when the change was expressed as a percentage of fetal size at 40 weeks' gestation. We have also shown how to obtain accurate conditional fetal velocity based on our previous methodological work. CONCLUSION: tools at https://intergrowth21.tghn.org/standards-tools/.