title: Effects of maternal smoking during pregnancy on offspring blood pressure in late adolescence.
abstract: OBJECTIVE
  Previous studies suggest that maternal smoking during pregnancy is associated with elevated offspring blood pressure during childhood. We aimed to investigate whether this association remained in late adolescence and, if so, whether it could be attributed to an intrauterine effect or to familial confounding.
  
  
  METHODS
  We used a national cohort of 87,223 young Swedish men born between 1983 and 1988 with information on both maternal smoking during pregnancy and blood pressure at military conscription. The cohort included 780 full brothers discordant for maternal smoking. Generalized estimation equations were used to estimate regression coefficients (β) with 95% confidence intervals (95% CIs).
  
  
  RESULTS
  We found a small but significant increase in both SBP and DBP for young men whose mothers had been daily smokers during pregnancy compared with sons of nonsmoking mothers: 0.26 (95% CI 0.09 to 0.44) and 0.45 mmHg (95% CI 0.31 to 0.59) for SBP and DBP, respectively. In a within-sibling analysis comparing full brothers discordant for maternal smoking exposure, point estimates were similar but not statistically significant: 0.85 (95% CI -0.19 to 1.90) for DBP and 0.81 (-0.56 to 2.19) for SBP.
  
  
  CONCLUSIONS
  Maternal smoking during pregnancy is associated with a small but statistically significant increase in offspring blood pressure in late adolescence. Because the association does not appear to be explained by familial confounding, our results support an intrauterine effect of prenatal smoking exposure on blood pressure in late adolescence.
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden. lovisa.hogberg@ki.se
authors.forename: Lovisa
authors.initials: L
authors.lastname: Högberg
authors.forename: Sven
authors.initials: S
authors.lastname: Cnattingius
authors.forename: Cecilia
authors.initials: C
authors.lastname: Lundholm
authors.forename: Brian M
authors.initials: BM
authors.lastname: D'Onofrio
authors.forename: Niklas
authors.initials: N
authors.lastname: Långström
authors.forename: Anastasia N
authors.initials: AN
authors.lastname: Iliadou
mesh_terms: D000293:Adolescent; D001724:Birth Weight; D001794:Blood Pressure / Q000187:drug effects* / Q000502:physiology; D015331:Cohort Studies; D005260:Female; D005865:Gestational Age; D006801:Humans; D006973:Hypertension / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D008297:Male; D018811:Maternal Exposure / Q000009:adverse effects*; D008431:Maternal-Fetal Exchange / Q000187:drug effects*; D011247:Pregnancy; D011256:Pregnancy Outcome; D011297:Prenatal Exposure Delayed Effects / Q000453:epidemiology / Q000209:etiology*; D012907:Smoking / Q000009:adverse effects*; D013548:Sweden / Q000453:epidemiology; D055815:Young Adult