Abstract

It is well established that boys are born heavier and longer than girls, but it remains unclear whether birth size in twins is affected by the sex of their co-twin. We conducted an individual-based pooled analysis of 21 twin cohorts in 15 countries derived from the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), including 67,850 dizygotic twin individuals. Linear regression analyses showed that boys having a co-twin sister were, on average, 31 g (95% CI 18 to 45) heavier and 0.16 cm (95% CI 0.045 to 0.274) longer than those with a co-twin brother. In girls, birth size was not associated (5 g birth weight; 95% CI −8 to −18 and −0.089 cm birth length; 95% CI −0.202 to 0.025) with the sex of the co-twin. Gestational age was slightly shorter in boy-boy pairs than in boy-girl and girl-girl pairs. When birth size was standardized by gestational age, the magnitude of the associations was attenuated in boys, particularly for birth weight. In conclusion, boys with a co-twin sister are heavier and longer at birth than those with a co-twin brother. However, these differences are modest and partly explained by a longer gestation in the presence of a co-twin sister.

Details

Title
Birth size and gestational age in opposite-sex twins as compared to same-sex twins: An individual-based pooled analysis of 21 cohorts
Author
Jelenkovic, Aline 1 ; Sund, Reijo 2   VIAFID ORCID Logo  ; Yokoyama, Yoshie 3 ; Yoon-Mi Hur 4 ; Ullemar, Vilhelmina 5 ; Almqvist, Catarina 6 ; Patrik KE Magnusson 5   VIAFID ORCID Logo  ; Willemsen, Gonneke 7 ; Bartels, Meike 7   VIAFID ORCID Logo  ; Catharina EM van Beijsterveldt 7 ; Bogl, Leonie H 8 ; Pietiläinen, Kirsi H 9 ; Vuoksimaa, Eero 8 ; Ji, Fuling 10 ; Feng, Ning 10 ; Pang, Zengchang 10 ; Nelson, Tracy L 11 ; Whitfield, Keith E 12 ; Rebato, Esther 13 ; Llewellyn, Clare H 14   VIAFID ORCID Logo  ; Fisher, Abigail 14 ; Bayasgalan, Gombojav 15 ; Narandalai, Danshiitsoodol 16 ; Bjerregaard-Andersen, Morten 17 ; Beck-Nielsen, Henning 18 ; Sodemann, Morten 19 ; Tarnoki, Adam D 20 ; Tarnoki, David L 20 ; Ooki, Syuichi 21 ; Stazi, Maria A 22 ; Fagnani, Corrado 22 ; Brescianini, Sonia 22 ; Dubois, Lise 23 ; Boivin, Michel 24 ; Brendgen, Mara 25 ; Dionne, Ginette 26 ; Vitaro, Frank 27 ; Cutler, Tessa L 28 ; Hopper, John L 29 ; Krueger, Robert F 30   VIAFID ORCID Logo  ; McGue, Matt 30 ; Pahlen, Shandell 30 ; Craig, Jeffrey M 31   VIAFID ORCID Logo  ; Saffery, Richard 31   VIAFID ORCID Logo  ; Claire MA Haworth 32 ; Plomin, Robert 33 ; Knafo-Noam, Ariel 34 ; Mankuta, David 35 ; Abramson, Lior 34 ; Burt, S Alexandra 36 ; Klump, Kelly L 36 ; Vlietinck, Robert F 37 ; Derom, Catherine A 38 ; Loos, Ruth JF 39   VIAFID ORCID Logo  ; Boomsma, Dorret I 7 ; Sørensen, Thorkild I A 40 ; Kaprio, Jaakko 8   VIAFID ORCID Logo  ; Silventoinen, Karri 41 

 Department of Social Research, University of Helsinki, Helsinki, Finland; Department of Genetics, Physical Anthropology and Animal Physiology, University of the Basque Country UPV/EHU, Leioa, Spain 
 Department of Social Research, University of Helsinki, Helsinki, Finland; Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland 
 Department of Public Health Nursing, Osaka City University, Osaka, Japan 
 Department of Education, Mokpo National University, Jeonnam, South Korea 
 Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden 
 Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden; Pediatric Allergy and Pulmonology Unit at Astrid Lindgren Children’s Hospital, Karolinska University Hospital, Stockholm, Sweden 
 Department of Biological Psychology, VU University Amsterdam, Amsterdam, Netherlands 
 Institute for Molecular Medicine FIMM, Helsinki, Finland; Department of Public Health, University of Helsinki, Helsinki, Finland 
 Obesity Research Unit, Research Programs Unit, University of Helsinki, Helsinki, Finland; Endocrinology, Abdominal Center, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland 
10  Department of Noncommunicable Diseases Prevention, Qingdao Centers for Disease Control and Prevention, Qingdao, China 
11  Department of Health and Exercise Sciencies and Colorado School of Public Health, Colorado State University, Fort Collins, USA 
12  Psychology and Neuroscience, Duke University, Durham, NC, USA 
13  Department of Genetics, Physical Anthropology and Animal Physiology, University of the Basque Country UPV/EHU, Leioa, Spain 
14  Health Behaviour Research Centre, Department of Epidemiology and Public Health, Institute of Epidemiology and Health Care, University College London, London, UK 
15  Healthy Twin Association of Mongolia, Ulaanbaatar, Mongolia 
16  Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan; Healthy Twin Association of Mongolia, Ulaanbaatar, Mongolia 
17  Bandim Health Project, INDEPTH Network, Bissau, Guinea-Bissau; Research Center for Vitamins and Vaccines, Statens Serum Institute, Copenhagen, Denmark; Department of Endocrinology, Odense University Hospital, Odense, Denmark 
18  Department of Endocrinology, Odense University Hospital, Odense, Denmark 
19  Department of Infectious Diseases, Odense University Hospital, Odense, Denmark 
20  Department of Radiology, Semmelweis University, Budapest, Hungary; Hungarian Twin Registry, Budapest, Hungary 
21  Department of Health Science, Ishikawa Prefectural Nursing University, Kahoku, Ishikawa, Japan 
22  Istituto Superiore di Sanità - Centre for Behavioural Sciences and Mental Health, Rome, Italy 
23  School of Epidemiology, Public Health and Preventive Medicine, University of Ottawa, Ottawa, Ontario, Canada 
24  École de psychologie, Université Laval, Québec, Canada; Institute of Genetic, Neurobiological, and Social Foundations of Child Development, Tomsk State University, Tomsk, Russian Federation 
25  Département de psychologie, Université du Québec à Montréal, Montréal, Québec, Canada 
26  École de psychologie, Université Laval, Québec, Canada 
27  École de psychoéducation, Université de Montréal, Montréal, Québec, Canada 
28  The Australian Twin Registry, Centre for Epidemiology and Biostatistics, The University of Melbourne, Melbourne, Victoria, Australia 
29  The Australian Twin Registry, Centre for Epidemiology and Biostatistics, The University of Melbourne, Melbourne, Victoria, Australia; Department of Epidemiology, School of Public Health, Seoul National University, Seoul, Korea 
30  Department of Psychology, University of Minnesota, Minneapolis, MN, USA 
31  Murdoch Childrens Research Institute, Royal Children’s Hospital, Parkville, Victoria, Australia; Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia 
32  MRC Integrative Epidemiology Unit, University of Bristol, Bristol, UK 
33  King’s College London, MRC Social, Genetic & Developmental Psychiatry Centre, Institute of Psychiatry, Psychology & Neuroscience, London, UK 
34  The Hebrew University of Jerusalem, Jerusalem, Israel 
35  Hadassah Hospital Obstetrics and Gynecology Department, Hebrew University Medical School, Jerusalem, Israel 
36  Michigan State University, East Lansing, Michigan, USA 
37  Centre of Human Genetics, University Hospitals Leuven, Leuven, Belgium 
38  Centre of Human Genetics, University Hospitals Leuven, Leuven, Belgium; Department of Obstetrics and Gynaecology, Ghent University Hospitals, Ghent, Belgium 
39  The Charles Bronfman Institute for Personalized Medicine, The Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA 
40  Novo Nordisk Foundation Centre for Basic Metabolic Research (Section of Metabolic Genetics), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Department of Public Health (Section of Epidemiology), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark 
41  Department of Social Research, University of Helsinki, Helsinki, Finland; Osaka University Graduate School of Medicine, Osaka University, Osaka, Japan 
Pages
1-8
Publication year
2018
Publication date
Apr 2018
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2027569924
Copyright
© 2018. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.