Document Type : Review Article
Authors
1 Social Determinants of Health Research Center, Institute for Futures Studies in Health, Kerman University of Medical Sciences, Kerman, Iran
2 Health Services Management Research Center, Institute for Futures Studies in Health, Kerman University of Medical Sciences, Kerman, Iran
Abstract
Background: There is much debate in the literature about the pros and cons of being an only child. However, there is a paucity of comprehensive reviews examining the consequences of being an only child on all levels of society. The purpose of this study is to explore the disadvantages of being only children on the health of the child, parents, and society as a whole.
Methods: The study is a narrative literature review of papers published in peer-reviewed journals between the year 2000 and October 2024 that address the drawbacks of being an only child. The papers were identified via a search of PsycInfo, PubMed, Google Scholar, and Google electronic databases. In total, thirty-six studies that explored and/or discussed the issue were identified. Then, the unhealthy effects of being an only child were summarized into three domains: individual, parents, and society.
Results: The study provides insight into the key health-related adverse effects of the only child phenomenon, specifically at the individual, family, and macro levels. The evidence from the reviewed literature suggests that being an only child leads to physical, psychological, and social harms on the health of the only child and parents, and hampers social development in the form of social harms such as an increase in divorce rates, sexual deviance, and a decline in social capital.
Conclusion: This review revealed the drawbacks of having one child, and some of the significant challenges families confront were identified. Further review is required to summarize the possible benefits of having only one child.
Keywords
Main Subjects
- Lin S, Chen B-B, Falbo T, Fong CJ, Guo J. Editorial: Chinese Only Children: Advantaged or Disadvantaged? Frontiers in Psychology. 2021;12: 742186. doi: 10.3389/fpsyg.2021.742186
- Howe N, Recchia H, Kinsley C. Sibling Relations and Their Impact on Children’s Development. In: Tremblay RE, Boivin M, Peters RDeV, eds. Boivin M, topic ed. Encyclopedia on Early Childhood Development [online]. https://www.child-encyclopedia.com/peer-relations/according-experts/sibling-relations-and-their-impact-childrens-development. Updated: March 2023. Accessed August 20, 2025.
- Howe N, Paine AL, Ross HS, Recchia H. Sibling relations in early and middle childhood. In: Smith PK, Hart CH, eds. The Wiley-Blackwell handbook of childhood social development. 2nd ed. Hoboken (New Jersey): Wiley-Blackwell Publishing; 2022: 443-458. doi: 10.1002/9781119679028.ch24
- Cameron L, Erkal N, Gangadharan L, Meng X. Little emperors: behavioral impacts of China's One-Child Policy. Science (New York, NY). 2013; 339(6122):953-7. doi: 1126/science.1230221
- Hesketh T, Zhu WX. Health in China: The one child family policy: the good, the bad, and the ugly. BMJ. 1997;314(7095):1685. doi: 10.1136/bmj.314.7095.1685
- Krynen C. The rise of single-child families: Psychologically harming the child. Intuition BYU Undergrad J Psychol. 2011;7:10-4. Accessed August 20, 2025. https://scholarsarchive.byu.edu/intuition/vol7/iss1/3
- Lo SMS. An investigation into the only-child effect on childhood development and adult outcomes [Internet]. 2024: 1-54. Available from: Available at SSRN: https://ssrn.com/abstract=4950159 or doi: 10.2139/ssrn.4950159.
- Bolderston A. Writing an effective literature review. Journal of Medical Imaging and Radiation Sciences. 2008; 39(2):86-92. doi: 10.1016/j.jmir.2008.04.009
- Green BN, Johnson CD, Adams A. Writing narrative literature reviews for peer-reviewed journals: secrets of the trade. Journal of chiropractic medicine. 2006; 5(3):101-17. doi: 10.1016/S0899-3467(07)60142-6
- Pautasso M. Ten simple rules for writing a literature review. PLoS computational biology. 2013;9(7):e1003149. doi: 10.1371/journal.pcbi.1003149
- Ferrari R. Writing narrative style literature reviews. Medical Writing. 2015;24(4):230-5. doi: 10.1179/2047480615Z.000000000329
- Grant MJ, Booth A. A typology of reviews: an analysis of 14 review types and associated methodologies. Health Information & Libraries Journal. 2009;26(2): 91-108. doi: 10.1111/j.1471-1842.2009.00848.x
- Xu C, Ju K, Lin L, Jia P, Kwong JSW, Syed A, et al. Rapid evidence synthesis approach for limits on the search date: How rapid could it be? Research Synthesis Methods. 2022;13(1): 68-76. doi: 10.1002/jrsm.1525
- World Health Organization. Constitution of the World Health Organization. 2006. Available from: https://www.who.int/publications/m/item/constitution-of-the-world-health-organization.
- Chen M, Li Y, Chen L, Gao D, Yang Z, Ma Y, et al. Associations Between Single-Child Status and Metabolic Syndrome in Children and Adolescents in China. Frontiers in Pediatrics. 2021;9:661164. doi: 3389/fped.2021.661164
- Pihlman J, Magnussen CG, Rovio SP, Pahkala K, Jokinen E, Laitinen TP, et al. Association between Number of Siblings and Cardiovascular Risk Factors in Childhood and in Adulthood: The Cardiovascular Risk in Young Finns Study. The Journal of Pediatrics. 2021;237:87-95. doi: 1016/j.jpeds.2021.05.058
- Rodrigues LP, Luz C, Cordovil R, Mendes R, Alexandre R, Lopes VP. Siblings’ Influence on the motor competence of preschoolers. Children. 2021;8(3):204. doi: 10.3390/children8030204
- Miller J, Ponsonby A-L, Pezic A, Kemp A, Piper SE, Akikusa JD, et al. Sibling Exposure and Risk of Juvenile Idiopathic Arthritis. Arthritis & Rheumatology. 2015;67(7):1951-8. doi: 10.1002/art.39129
- Keenan K, Barclay K, Goisis A. Health outcomes of only children across the life course: An investigation using Swedish register data. Population studies. 2023;77(1):71-90. doi: 10.1080/00324728.2021.2020886
- Chanfreau J, Barclay K, Keenan K, Goisis A. Sibling group size and BMI over the life course: Evidence from four British cohort studies. Advances in Life Course Research. 2022;53:100493. doi: 10.1016/j.alcr.2022.100493
- Meller FO, Loret de Mola C, Assunção MCF, Schäfer AA, Dahly DL, Barros FC. Birth order and number of siblings and their association with overweight and obesity: a systematic review and meta-analysis. Nutrition Reviews. 2018;76(2):117-24. doi: 10.1093/nutrit/nux060
- Wang D, Kato N, Inaba Y, Tango T, Yoshida Y, Kusaka Y, et al. Physical and personality traits of preschool children in Fuzhou, China: only child vs sibling. Child: Care, Health and Development. 2000; 26(1):49-60. doi: 10.1046/j.1365-2214.2000.00143.x
- Kantojärvi L, Joukamaa M, Miettunen J, Läksy K, Herva A, Karvonen J, et al. Childhood family structure and personality disorders in adulthood. European Psychiatry. 2008;23(3):205-11. doi: 10.1016/j.eurpsy.2007.11.005
- Molini-Avejonas DR, Ferreira LV, Amato CAdLH. Risk Factors for Speech-Language Pathologies in Children. In: Fernanda Dreux MF, editor. Advances in Speech-language Pathology. Croatia, Rijeka: IntechOpen; 2017. p. Ch. 15. doi: 10.5772/intechopen.70107
- Rodrigues LP, Lima RF, Silva AF, Clemente FM, Camões M, Nikolaidis PT, et al. Physical Fitness and Somatic Characteristics of the Only Child. Frontiers in Pediatrics. 2020; 8: 324. doi: 10.3389/fped.2020.00324
- Fukuya Y, Fujiwara T, Isumi A, Doi S, Ochi M. Association of Birth Order With Mental Health Problems, Self-Esteem, Resilience, and Happiness Among Children: Results From A-CHILD Study. Frontiers in Psychiatry. 2021;12:638088. doi: 10.3389/fpsyt.2021.638088
- Cheng S, Jia C, Wang Y. Only children were associated with anxiety and depressive symptoms among college students in China. International journal of environmental research and public health. 2020; 17(11):4035. doi: 10.3390/ijerph17114035
- Mangolian Shahrbabaki P, Dehghan M, Maazallahi M, Asadi N. Fear and anxiety in girls aged 7 to 11 years old and related factors during the coronavirus pandemic. Clinical Child Psychology and Psychiatry. 2022; 27(1):259-68. doi: 10.1177/13591045211013873
- Sheng L, Yang B, Story M, Wu W, Xi X, Zhou Y, et al. Emotional and Behavioral Changes and Related Factors of Firstborn School-Aged Compared to Same Age Only Children. Frontiers in Public Health. 2022;10: 822761. doi: 10.3389/fpubh.2022.822761
- Wu S, Zhang D, Li X, Zhao J, Sun X, Shi L, et al. Siblings and early childhood development: evidence from a population-based cohort in preschoolers from Shanghai. International Journal of Environmental Research and Public Health. 2022;19(9):5739. doi: 10.3390/ijerph19095739
- Wang Y, Lin Y, Jiang D, Liu L, Lin S, He J, et al. Differences in close-work activities and optical axis length between only children and non-only children: a cross-sectional study. BMC pediatrics. 2022;22(1):538. doi: 10.1186/s12887-022-03586-7
- Zhao L, Zhou M. Do only children have poor vision? Evidence from C hina's O ne‐C hild P olicy. Health economics. 2018;27(7):1131-46. doi: 10.1002/hec.3661
- Wei Y, Jiang Q, Gietel-Basten S. The well-being of bereaved parents in an only-child society. Death Studies. 2016;40(1):22-31. doi: 10.1080/07481187.2015.1056563
- Li S, Chen R, Cao Y, Li J, Zuo D, Yan H. Sexual knowledge, attitudes and practices of female undergraduate students in Wuhan, China: The only-child versus students with siblings. PLoS One. 2013;8(9):e73797. doi: 10.1371/journal.pone.0073797
- Qi R, Luo Y, Zhang L, Weng Y, Surento W, Xu Q, et al. Decreased functional connectivity of hippocampal subregions and methylation of the NR3C1 gene in Han Chinese adults who lost their only child. Psychological medicine. 2021;51(8):1310-9. doi:10.1017/S0033291720000045
- Jiang Q, Li S, Feldman MW. China’s population policy at the crossroads: Social impacts and prospects. Asian journal of social science. 2013;41(2):193-218. doi: 10.1163/15685314-12341298
- Gui T, Koropeckyj-Cox T. “I am the only child of my parents:” perspectives on future elder care for parents among Chinese only-children living overseas. Journal of Cross-Cultural Gerontology. 2016;31:255-75. doi: 10.1007/s10823-016-9295-z
- Bobbitt-Zeher D, Downey DB, Merry J. Number of siblings during childhood and the likelihood of divorce in adulthood. Journal of family issues. 2016;37(15):2075-94. doi: 10.1177/0192513X14560641
- Skalkidou A. Parental family variables and likelihood of divorce. Sozial- und Präventivmedizin. 2000;45(2):95-101. doi: 10.1007/BF01624617
- Kemppainen L, Jokelainen J, Järvelin M-R, Isohanni M, Räsänen P. The one-child family and violent criminality: a 31-year follow-up study of the Northern Finland 1966 Birth Cohort. American Journal of Psychiatry. 2001;158(6):960-2. doi: 10.1176/appi.ajp.158.6.960
- Zhao S, Liang Y, Hee JY, Qi X, Tang K. Difference in the sexual and reproductive health of only-child students and students with siblings, according to sex and region: Findings from the National College Student Survey. Frontiers in Public Health. 2022;10. doi: 10.3389/fpubh.2022.925626
- Li J. Parents' Experiences After the Death of an Only Child in the US: FIU Electronic Theses and Dissertations. 4670; 2021. doi: 10.25148/etd.FIDC009580
- Feng Z, Diao Y, Ma H, Liu M, Long M, Zhao S, et al. Mobile phone addiction and depression among Chinese medical students: the mediating role of sleep quality and the moderating role of peer relationships. BMC psychiatry. 2022;22(1):567. doi: 10.1186/s12888-022-04183-9
- Lee J, Lim H, Allen J, Choi G, Jung J. Smartphone addiction and depression among low-income boys since COVID-19: the moderating effect of being an only child. Healthcare. 2021;9(10):1350. doi: 10.3390/healthcare9101350
- Lao Y, Lin S. Comparison of educational performance between the only children and children in two-child families. Scientific Reports. 2022;12(1): 15355: 1-16. doi: 10.1038/s41598-022-19730-3
- Tani Y, Isumi A, Doi S, Fujiwara T. Number of Siblings and Social Capital Among Parents Rearing Schoolchildren: Results From the A-CHILD Study. Journal of Epidemiology. 2023; 33(9):478-83. doi: 2188/jea.JE20210510
- Pantke PM, Herrmann-Lingen C, Rothenberger A, Poustka L, Meyer T. Is only-child status associated with a higher blood pressure in adolescence? An observational study. European Journal of Pediatrics. 2023;182(3):1377-84. doi: 10.1007/s00431-022-04800-5
- Park J, Chandran A. Associations of only-child status with health outcomes and risky behaviors in Korean middle- and high-school students: An outcome-wide analysis. Preventive Medicine Reports. 2023; 31:102101. doi: 10.1016/j.pmedr.2022.102101
- Palman J, Shoop-Worrall S, Hyrich K, McDonagh JE. Update on the epidemiology, risk factors and disease outcomes of Juvenile idiopathic arthritis. Best Practice & Research Clinical Rheumatology. 2018;32(2):206-22. doi: 10.1016/j.berh.2018.10.004
- Stradford L, van Poppel F, Lumey LH. Can resource dilution explain differences in height by birth order and family size? A study of 389,287 male recruits in twentieth-century Netherlands. The History of the Family. 2017;22(2-3):214-35. doi: 10.1080/1081602X.2016.1230510
- Fariba K, Gupta V, Kass E. Personality Disorder. StatPearls Publishing; 2022. Available from: https://www.ncbi.nlm.nih.gov/books/NBK556058/.
- Jiang Q, Li Y, Sánchez-Barricarte JJ. The risk of mothers losing an only child in China. Journal of Biosocial Science. 2014;46(4):531-45. doi: 10.1017/S0021932013000540
- Wang Y, Fong VL. Little emperors and the 4: 2: 1 Generation: China’s singletons. Journal of the American Academy of Child and Adolescent Psychiatry. 2009;48(12):1137-9. doi: 10.1097/CHI.0b013e3181bc72f8
- Murphy R. Dysgenics: Genetic deterioration in modern populations, Richard Lynn., London. Ulster Institute for Social Research, 2011. Personality and Individual Differences. 2012; 52(3):462. doi: 10.1016/j.paid.2011.10.039
- Mancillas, A. Challenging the Stereotypes About Only Children: A Review of the Literature and Implications for Practice. Journal of Counseling & Development. 2006;84(3):268-75. doi: 10.1002/j.1556-6678.2006.tb00405.x