Infertility, infertility treatment and psychomotor development: the Danish National Birth Cohort
Article first published online: 7 JAN 2009
Journal compilation © 2009 Blackwell Publishing Ltd. No claim to original US government works
Paediatric and Perinatal Epidemiology
Volume 23, Issue 2, pages 98–106, March 2009
How to Cite
Zhu, J. L., Basso, O., Obel, C., Hvidtjørn, D. and Olsen, J. (2009), Infertility, infertility treatment and psychomotor development: the Danish National Birth Cohort. Paediatric and Perinatal Epidemiology, 23: 98–106. doi: 10.1111/j.1365-3016.2008.00989.x
- Issue published online: 20 JAN 2009
- Article first published online: 7 JAN 2009
- child development;
- assisted reproduction;
- time to pregnancy
Babies born of infertile couples, regardless of treatment, have a higher risk of preterm birth and low birthweight, conditions associated with delayed development. We examined developmental milestones in singletons as a function of parental infertility [time to pregnancy (TTP) > 12 months] and infertility treatment. From the Danish National Birth Cohort (1997–2003), we identified 37 897 singletons born of fertile couples (TTP ≤ 12 months), 4351 born of infertile couples conceiving naturally (TTP > 12 months), and 3309 born after infertility treatment. When the children were about 18 months old, mothers reported 12 developmental milestones by responding to structured questions. We defined a failure to achieve the assessed milestone or the minimal numbers of milestones in a summary (motor, or cognitive/language skills) as delay.
Naturally conceived children born of infertile couples had a pattern of psychomotor development similar to that of children born of fertile couples, but increasing TTP correlated with a modest delay. When the analysis was restricted to infertile couples (treated and untreated), children born after treatment showed a slight delay in cognitive/language development (odds ratio 1.24, [95% confidence interval 1.01, 1.53]) for not meeting at least three out of six cognitive/language milestones); children born after intracytoplasmic sperm injection (ICSI) had the highest estimated relative risk of delay for most milestones, especially motor milestones. These results suggest that a long TTP may be associated with a modest developmental delay. Infertility treatment, especially ICSI, may be associated with a slight delay for some of these early milestones.