| dc.description.abstract | Studies investigating the role of increasing paternal age for neonatal health in pregnancies following assisted reproductive technology (ART) are limited. In this large cohort study, we evaluated the association between paternal age and preterm birth, SGA, perinatal death, gestational age and birth weight. We compared these associations between singleton pregnancies following spontaneous conception (SC) and ART conception (in vitro fertilization, IVF and intra-cytoplasmic sperm injection, ICSI). We used data from the Medical Birth Registry of Norway including 1 508 364 singleton births in the period 1988 to 2010. Each birth outcome was analyzed across paternal age as a continuous variable and categorical variable (25-29, 30-34, 35-39, 40-44, 45-49, 50-54 and ≥ 55). We used logistic and linear regression models and adjusted for maternal age, offspring sex, birth year, gestational age and parity. We found that the risk of SGA (OR 1.06, 95% CI 1.05 to 1.07) and perinatal death (OR 1.05, 95% CI 1.02 to 1.08) increased with five years increase in paternal age in SC pregnancies. For ART pregnancies, the risk of SGA was higher in pregnancies with paternal age between 30 and 44 years compared to 25 to 29 years (OR 1.34, 95% CI 0.91 to 1.95 for paternal age 40 to 44 years), but there were no clear trends across the range of paternal ages for any outcomes in ART pregnancies. In conclusion, increasing paternal age is not associated with increased risk of SGA, preterm birth, perinatal death, lower mean gestational age or mean birth SGA, preterm birth, perinatal death, lower mean gestational age or mean birth weight in ART pregnancies, but modestly associated with risk of SGA and perinatal death in SC pregnancies. | nb_NO |