title: The World Health Organization Fetal Growth Charts: A Multinational Longitudinal Study of Ultrasound Biometric Measurements and Estimated Fetal Weight.
abstract: Perinatal mortality and morbidity continue to be major global health challenges strongly associated with prematurity and reduced fetal growth, an issue of further interest given the mounting evidence that fetal growth in general is linked to degrees of risk of common noncommunicable diseases in adulthood. Against this background, WHO made it a high priority to provide the present fetal growth charts for estimated fetal weight (EFW) and common ultrasound biometric measurements intended for worldwide use.
  
  
  
  We conducted a multinational prospective observational longitudinal study of fetal growth in low-risk singleton pregnancies of women of high or middle socioeconomic status and without known environmental constraints on fetal growth. Centers in ten countries (Argentina, Brazil, Democratic Republic of the Congo, Denmark, Egypt, France, Germany, India, Norway, and Thailand) recruited participants who had reliable information on last menstrual period and gestational age confirmed by crown-rump length measured at 8-13 wk of gestation. Participants had anthropometric and nutritional assessments and seven scheduled ultrasound examinations during pregnancy. Fifty-two participants withdrew consent, and 1,387 participated in the study. At study entry, median maternal age was 28 y (interquartile range [IQR] 25-31), median height was 162 cm (IQR 157-168), median weight was 61 kg (IQR 55-68), 58% of the women were nulliparous, and median daily caloric intake was 1,840 cal (IQR 1,487-2,222). The median pregnancy duration was 39 wk (IQR 38-40) although there were significant differences between countries, the largest difference being 12 d (95% CI 8-16). The median birthweight was 3,300 g (IQR 2,980-3,615). There were differences in birthweight between countries, e.g., India had significantly smaller neonates than the other countries, even after adjusting for gestational age. Thirty-one women had a miscarriage, and three fetuses had intrauterine death. The 8,203 sets of ultrasound measurements were scrutinized for outliers and leverage points, and those measurements taken at 14 to 40 wk were selected for analysis. A total of 7,924 sets of ultrasound measurements were analyzed by quantile regression to establish longitudinal reference intervals for fetal head circumference, biparietal diameter, humerus length, abdominal circumference, femur length and its ratio with head circumference and with biparietal diameter, and EFW. There was asymmetric distribution of growth of EFW: a slightly wider distribution among the lower percentiles during early weeks shifted to a notably expanded distribution of the higher percentiles in late pregnancy. Male fetuses were larger than female fetuses as measured by EFW, but the disparity was smaller in the lower quantiles of the distribution (3.5%) and larger in the upper quantiles (4.5%). Maternal age and maternal height were associated with a positive effect on EFW, particularly in the lower tail of the distribution, of the order of 2% to 3% for each additional 10 y of age of the mother and 1% to 2% for each additional 10 cm of height. Maternal weight was associated with a small positive effect on EFW, especially in the higher tail of the distribution, of the order of 1.0% to 1.5% for each additional 10 kg of bodyweight of the mother. Parous women had heavier fetuses than nulliparous women, with the disparity being greater in the lower quantiles of the distribution, of the order of 1% to 1.5%, and diminishing in the upper quantiles. There were also significant differences in growth of EFW between countries. In spite of the multinational nature of the study, sample size is a limiting factor for generalization of the charts.
  
  
  
  This study provides WHO fetal growth charts for EFW and common ultrasound biometric measurements, and shows variation between different parts of the world.
authors.affiliation: Department of Obstetrics and Gynecology, Haukeland University Hospital, Bergen, Norway.|Department of Clinical Science, University of Bergen, Bergen, Norway.
authors.forename: Torvid
authors.identifier: 0000-0003-1825-1660
authors.initials: T
authors.lastname: Kiserud
authors.affiliation: Medical Statistics Department, London School of Hygiene &Tropical Medicine, London, United Kingdom.|Statistika Consultoria, São Paulo, Brazil.
authors.forename: Gilda
authors.identifier: 0000-0002-9885-8392
authors.initials: G
authors.lastname: Piaggio
authors.affiliation: Centro Rosarino de Estudios Perinatales, Rosario, Argentina.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Carroli
authors.affiliation: Department of Reproductive Health and Research, UNDP/UNFPA/UNICEF/WHO/World Bank Special Programme of Research, Development and Research Training in Human Reproduction, World Health Organization, Geneva, Switzerland.
authors.forename: Mariana
authors.initials: M
authors.lastname: Widmer
authors.affiliation: Statistika Consultoria, São Paulo, Brazil.
authors.forename: José
authors.identifier: 0000-0002-8901-9802
authors.initials: J
authors.lastname: Carvalho
authors.affiliation: Center of Fetal Medicine, Department of Obstetrics, Rigshospitalet, Copenhagen University, Copenhagen, Denmark.
authors.forename: Lisa
authors.initials: L
authors.lastname: Neerup Jensen
authors.affiliation: Centro Rosarino de Estudios Perinatales, Rosario, Argentina.
authors.forename: Daniel
authors.initials: D
authors.lastname: Giordano
authors.affiliation: Department of Obstetrics and Gynecology, School of Medical Sciences, University of Campinas, Campinas, Brazil.
authors.forename: José Guilherme
authors.identifier: 0000-0003-1285-8445
authors.initials: JG
authors.lastname: Cecatti
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, Assiut University, Assiut, Egypt.
authors.forename: Hany
authors.initials: H
authors.lastname: Abdel Aleem
authors.affiliation: Department of Exercise and Nutrition Sciences, Milken Institute School of Public Health, George Washington University, Washington, District of Columbia, United States of America.
authors.forename: Sameera A
authors.initials: SA
authors.lastname: Talegawkar
authors.affiliation: Service de Gynecologie Obstetrique, Hôpital Antoine-Béclère, AP-HP, Université Paris Sud, Clamart, France.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Benachi
authors.affiliation: Department for Obstetrics and Fetal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Anke
authors.initials: A
authors.lastname: Diemert
authors.affiliation: École de Santé Publique, Faculté de Medecine, Université de Kinshasa, Kinshasa, Democratic Republic of the Congo.
authors.forename: Antoinette
authors.initials: A
authors.lastname: Tshefu Kitoto
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Jadsada
authors.initials: J
authors.lastname: Thinkhamrop
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Pisake
authors.initials: P
authors.lastname: Lumbiganon
authors.affiliation: Center of Fetal Medicine, Department of Obstetrics, Rigshospitalet, Copenhagen University, Copenhagen, Denmark.
authors.forename: Ann
authors.initials: A
authors.lastname: Tabor
authors.affiliation: Department of Obstetrics and Gynecology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Alka
authors.initials: A
authors.lastname: Kriplani
authors.affiliation: División de Obstetricia y Ginecología, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: Rogelio
authors.initials: R
authors.lastname: Gonzalez Perez
authors.affiliation: Department for Obstetrics and Fetal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Kurt
authors.initials: K
authors.lastname: Hecher
authors.affiliation: Institute of Developmental Sciences, University of Southampton, Southampton, United Kingdom.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Hanson
authors.affiliation: Department of Reproductive Health and Research, UNDP/UNFPA/UNICEF/WHO/World Bank Special Programme of Research, Development and Research Training in Human Reproduction, World Health Organization, Geneva, Switzerland.
authors.forename: A Metin
authors.initials: AM
authors.lastname: Gülmezoglu
authors.affiliation: David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, United States of America.|Center for Fetal Medicine and Women's Ultrasound, Los Angeles, California, United States of America.
authors.forename: Lawrence D
authors.initials: LD
authors.lastname: Platt
mesh_terms: D000328:Adult; D000886:Anthropometry; D005260:Female; D047109:Fetal Development; D020567:Fetal Weight; D014943:Global Health; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D011247:Pregnancy; D011446:Prospective Studies; D012016:Reference Values; D014463:Ultrasonography; D055815:Young Adult