International standards for symphysis-fundal height based on serial measurements from the Fetal Growth Longitudinal Study of the INTERGROWTH-21st Project: prospective cohort study in eight countries.
OBJECTIVE
To create international symphysis-fundal height standards derived from pregnancies of healthy women with good maternal and perinatal outcomes.


METHODS
Prospective longitudinal observational study.


METHODS
Eight geographically diverse urban regions in Brazil, China, India, Italy, Kenya, Oman, United Kingdom, and United States.


METHODS
Healthy, well nourished pregnant women enrolled into the Fetal Growth Longitudinal Study component of the INTERGROWTH-21stProject at 9-14 weeks' gestation, and followed up until birth.


METHODS
Symphysis-fundal height was measured every five weeks from 14 weeks' gestation until birth using standardised methods and dedicated research staff who were blinded to the symphysis-fundal height measurements by turning the tape measure so that numbers were not visible during examination. The best fitting curve was selected using second degree fractional polynomials and further modelled in a multilevel framework to account for the longitudinal design of the study.


RESULTS
Of 13 108 women screened in the first trimester, 4607 (35.1%) met the study entry criteria. Of the eligible women, 4321 (93.8%) had pregnancies without major complications and delivered live singletons without congenital malformations. The median number of symphysis-fundal height measurements was 5.0 (range 1-7); 3976 (92.0%) women had four or more measurements. Symphysis-fundal height measurements increased almost linearly with gestational age; data were used to determine fitted 3rd, 50th, and 97th centile curves, which showed excellent agreement with observed values.


CONCLUSIONS
This study presents international standards to measure symphysis-fundal height as a first level screening tool for fetal growth disturbances.
Nuffield Department of Obstetrics & Gynaecology and Oxford Maternal & Perinatal Health Institute, Green Templeton College, University of Oxford, Oxford, UK aris.papageorghiou@obs-gyn.ox.ac.uk.
Aris T
AT
Papageorghiou
Nuffield Department of Obstetrics & Gynaecology and Oxford Maternal & Perinatal Health Institute, Green Templeton College, University of Oxford, Oxford, UK.|Centre for Statistics in Medicine, Nuffield Department of Orthopaedics, Rheumatology & Musculoskeletal Sciences, University of Oxford, Oxford, UK.
Eric O
EO
Ohuma
Center for Perinatal Studies, Swedish Medical Center, Seattle, WA, USA.|Global Alliance to Prevent Prematurity and Stillbirth, Seattle, WA, USA.
Michael G
MG
Gravett
Nuffield Department of Obstetrics & Gynaecology and Oxford Maternal & Perinatal Health Institute, Green Templeton College, University of Oxford, Oxford, UK.
Jane
J
Hirst
Departamento Materno-Infantil, Universidade Federal de Pelotas, Pelotas, RS, Brazil.|Programa de Pós-Graduação em Epidemiologia, Universidade Federal de Pelotas, Pelotas, RS, Brazil.
Mariangela F
MF
da Silveira
Nuffield Department of Obstetrics & Gynaecology and Oxford Maternal & Perinatal Health Institute, Green Templeton College, University of Oxford, Oxford, UK.
Ann
A
Lambert
Faculty of Health Sciences, Aga Khan University, Nairobi, Kenya.
Maria
M
Carvalho
Department of Family & Community Health, Ministry of Health, Muscat, Sultanate of Oman.
Yasmin A
YA
Jaffer
Centre for Statistics in Medicine, Nuffield Department of Orthopaedics, Rheumatology & Musculoskeletal Sciences, University of Oxford, Oxford, UK.
Douglas G
DG
Altman
Department of Engineering Science, University of Oxford, Oxford, UK.
Julia A
JA
Noble
Dipartimento di Scienze Pediatriche e dell'Adolescenza, Cattedra di Neonatologia, Università degli Studi di Torino, Turin, Italy.
Enrico
E
Bertino
Nagpur INTERGROWTH-21st Research Centre, Ketkar Hospital, Nagpur, India.
Manorama
M
Purwar
School of Public Health, Peking University, Beijing, China.
Ruyan
R
Pang
Nuffield Department of Obstetrics & Gynaecology and Oxford Maternal & Perinatal Health Institute, Green Templeton College, University of Oxford, Oxford, UK.
Leila
L
Cheikh Ismail
Programa de Pós-Graduação em Epidemiologia, Universidade Federal de Pelotas, Pelotas, RS, Brazil.
Cesar
C
Victora
Division of Women & Child Health, Aga Khan University, Karachi, Pakistan.
Zulfiqar A
ZA
Bhutta
Nuffield Department of Obstetrics & Gynaecology and Oxford Maternal & Perinatal Health Institute, Green Templeton College, University of Oxford, Oxford, UK.
Stephen H
SH
Kennedy
Nuffield Department of Obstetrics & Gynaecology and Oxford Maternal & Perinatal Health Institute, Green Templeton College, University of Oxford, Oxford, UK.
José
J
Villar
D000005:Abdomen / Q000033:anatomy & histology*; D000328:Adult; D000886:Anthropometry; D005260:Female; D047109:Fetal Development / Q000502:physiology*; D005317:Fetal Growth Retardation / Q000175:diagnosis; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D008137:Longitudinal Studies; D008297:Male; D011247:Pregnancy; D011446:Prospective Studies; D011631:Pubic Symphysis; D016216:Ultrasonography, Prenatal / Q000592:standards*