Previous research revealed that children born from threatened abortion (TAB)-affected gestation are at 2-3 fold increased risk of autism spectrum disorders and developmental coordination disorder. In conventional cohort analysis, TAB-affected children had a 21-25% higher relative risk of epilepsy, attention-deficit/hyperactivity disorder (ADHD), in the first 16 years of life and 42% higher relative risk of cerebral palsy in the first 6 years of life. After removal of time-invariant family-shared confounding in sibling analyses, the association of being affected by TAB in gestation with epilepsy and ADHD was attenuated, but persisted for cerebral palsy. There was little evidence for an increased risk of epilepsy and ADHD following birth from a TAB-affected pregnancy. We could not rule out a substantial association between being TAB-affected in pregnancy and cerebral palsy on the relative scale. However, on the absolute scale, the association was weak.