Social consequences of preterm birth : aregister-based cohort study of children born preterm in 1987 - 1990 in Finland

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Background. Preterm birth (birth before 37 completed weeks of gestation) is associated with a range of health, behavioral and cognitive challenges with possible individual and family-level implications. However, most of the individuals and families exposed to preterm birth cope well. While the impact of preterm and early term (birth at 37 to 38 weeks’ gestation) on a range of health outcomes has been extensively studied, less is known about the impact of gestational age (GA) on other life-course events. Aim. To examine how different degrees of preterm and early term birth predict subsequent sibling birth, placement to out-of-home care (OHC), educational attainment, and risk-taking behavior. Methods. The study was based on the Finnish 1987-1990 Birth Cohort, which comprises all children live-born in Finland between January 1, 1987, and September 30, 1990 (n = 235 624). The Finnish 1987-1990 Birth Cohort is in turn based on the Finnish Medical Birth Register (FMBR), to which individual-level register data from eleven nationwide administrative registers were merged, yielding a broad dataset on different aspects of life. The eleven registers from which the data were merged are: (1) the Central Population Register, (2) the Register of Congenital Malformations, (3) the Register of Child Welfare, (4) The Register on abortions, (5) the Care Register for Health Care, (6) National Infectious Diseases Register, (7) The Census Register, (8) The registers of the National Social Insurance Institution of Finland, (9) The register on crimes, (10) the register on fines and punishments, and (11) the registers of credit defaults maintained by Suomen Asiakastieto Oy. Register records on sexually transmitted Chlamydia trachomatis infections (STCT), teenage pregnancies, payment defaults, criminal offending, and substance abuse served as proxies for risk-taking behavior. To ensure enough cases for the analyses, GA was divided into five to seven subgroups or treated as a continuous variable. Multinomial logistic regression, linear regression, and Cox regression served as statistical methods. The mediating and modifying factors were controlled for and time-dependent variables employed when needed. Propensity score was utilized for adjustment and matching for central background characteristics, and restricted cubic spline models were employed to test for trend between GA and the outcomes. Results. 1) Mothers of extremely preterm (23-27 completed weeks) infants were, compared with mothers of full-term infants (39-41 weeks), 0.74-fold less likely to have a subsequent live-born child. Among mothers of infants born at 28 to 38 weeks’ gestation, the likelihood was 0.72 to 0.90-fold lower. Within the cohort, the number of “missing siblings” caused by the lower likelihood of subsequent children associated with preterm birth exceeded over 3-fold the number of preterm born children who died. 2) The more preterm an individual was, the higher was the risk of OHC placement at 0 to 5 years of age, indicating a dose-response relationship between the gestational age (GA) and placement risk. Those born at 23 to 33 weeks or late preterm (34 to 36 weeks) had a 2.29- to 1.76-fold higher risk of OHC than their full-term born controls. No excess risk for OHC existed after age 5, according to GA. 3) The likelihood of attending special education (SE) in compulsory school increased by declining GA. Those born extremely preterm had 5.48-fold rates for SE, as compared to those born full-term. In mainstream education, those born extremely preterm had marginally lower mathematics grades compared with full-term counterparts, whereas those born late preterm or early term had slightly higher grades. Adolescents born at 28-31 weeks’ gestation had lower physical education grades. Education at age 25, however, was unassociated with GA among those who attended mainstream education. Likewise, the associations between school grades at age 16 and completed education at age 25 did not vary by GA among them. 4) There was also a linear dose-response relationship between the GA and STCT and teenage pregnancy: each week decrease in GA resulted in a 1.6% and 3.3% lower risk of STCT and teenage pregnancy respectively. Those born extremely preterm had a 51% lower risk for criminal offending than their full-term born counterparts, while those born very preterm had a 28% higher likelihood for payment defaults than their full-term born peers. GA was not associated with substance abuse. Conclusion. Most individuals and families with experiences of preterm birth fare well. However, at group level, families with a preterm born child experience adversities and strain that may reflect increased parental burden associated with preterm birth and might need more attention and support from healthcare professionals and service systems. As the child grows older, prospects might be somewhat brighter: while those born preterm are in special education more frequently, those in mainstream education get along similarly to their full-term born peers, with only minor differences, and later attain the same level of education. In adolescence and young adulthood, those born preterm engage in less risk-taking in terms of sexual and, to a lesser extent, criminal behavior.
  • Hovi, Petteri, Handledare
  • Kajantie, Eero, Handledare
Tryckta ISBN978-951-51-9383-4
Elektroniska ISBN978-951-51-9384-1
StatusPublicerad - 2023
MoE-publikationstypG5 Doktorsavhandling (artikel)

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  • 3123 Kvinno- och barnsjukdomar

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