Background: Antidepressant use during pregnancy has increased over the last decades, while safety has been under debate. Our aim was to measure the international prevalence of antidepressant use before, during, and after pregnancy and examine timing, type of prescriptions and geographic variability. Methods: We searched Embase, Medline Ovid, Web of Science, Cochrane Central and Google Scholar from their inception until February 19, 2019. We determined pooled prevalence estimates of antidepressants before, during, and after pregnancy, as well as stratified according to substantive variables. Results: We identified 40 cohorts from 15 countries, together reporting on 14,072,251 pregnancies. Included studies had a low risk of bias, often reporting on large representative cohorts. Selective serotonin reuptake inhibitors (SSRIs) were the most commonly used antidepressants during pregnancy, with an international prevalence estimate of 3.0% (95%CI 2.3;3.7). While Europe and Australasia had pooled prevalence estimates of 1.6% and 1.3% respectively, Northern America had a prevalence estimate of 5.5% (Q-value = 126.19; df = 2; p-value<0.01). Highest SSRI prevalence rates were found for sertraline (1.10%), followed by citalopram and fluoxetine (0.77% and 0.76% respectively) (Q-value = 121.25; df = 5; p-value<0.01). Qualitative analysis indicated an increase in antidepressant use over subsequent calendar years. Limitations: Substantial heterogeneity remained unaccounted for throughout the analyses, even after accounting for hypothetical contributors. Conclusions: This meta-analysis revealed substantial regional differences in antidepressant use around pregnancy, which could be due to variability in prescription behavior, healthcare seeking behavior and organization of healthcare. There is an urgent need for evidence on effectiveness, benefit, and harm of antidepressants during pregnancy to guide clinical practice. greatly contribute to this increase (Andrade et al., 2016;Charlton et al., 2015;Cooper et al., 2007). In the general population, antidepressants are now among the top three most commonly prescribed therapeutic drug classes in the United States (Pratt et al., 2017). Antidepressants showed the largest increase in prescriptions during pregnancy over time, compared to other drugs associated with potential harmful neonatal effects (van Gelder et al., 2014).

ObjectivePreterm birth has been associated with an increased risk of attention-deficit/hyperactivity disorder (ADHD)–like symptoms and cognitive impairments similar to those seen in ADHD, including attention and inhibitory control difficulties. Yet data on direct comparisons across ADHD and preterm birth on cognitive-neurophysiological measures are limited.MethodWe directly compared 186 preterm-born adolescents to 69 term-born adolescents with ADHD and 135 term-born controls on cognitive-performance and event-related potential measures associated with attentional and inhibitory processing from a cued continuous performance test (CPT-OX), which we have previously shown to discriminate between the adolescents with ADHD and controls. We aimed to elucidate whether the ADHD-like symptoms and cognitive impairments in preterm-born individuals reflect identical cognitive-neurophysiological impairments in term-born individuals with ADHD.ResultsGo-P3 amplitude was reduced, reflecting impaired executive response control, in preterm-born adolescents compared to both controls and adolescents with ADHD. Moreover, in preterm-born adolescents, as in term-born adolescents with ADHD, contingent negative variation amplitude was attenuated, reflecting impairments in response preparation compared to controls. Although the ADHD group showed significantly increased NoGo-P3 amplitude at FCz compared to preterm group, at Cz preterm-born adolescents demonstrated significantly decreased NoGo-P3 amplitude compared to the control group, similar to term-born adolescents with ADHD.ConclusionThese findings indicate impairments in response preparation, executive response control, and response inhibition in preterm-born adolescents. Although the response preparation and response inhibition impairments found in preterm-born adolescents overlap with those found in term-born adolescents with ADHD, the preterm group also shows unique impairments, suggesting more wide-ranging impairments in the preterm group compared to the ADHD group.

While the negative association between ADHD symptoms and IQ is well documented, our knowledge about the direction and aetiology of this association is limited. Here, we examine the association of ADHD symptoms with verbal and performance IQ longitudinally in a population-based sample of twins. In a population-based sample of 4,771 twin pairs, DSM-IV ADHD symptoms were obtained from the Conners’ Parent Rating Scale-Revised. Verbal (vocabulary) and performance (Raven’s Progressive Matrices) IQ were assessed online. ADHD symptom ratings and IQ scores were obtained at ages 12, 14 and 16 years. Making use of the genetic sensitivity and time-ordered nature of our data, we use a cross-lagged model to examine the direction of effects, while modelling the aetiologies of the association between ADHD symptoms with vocabulary and Raven’s scores over time. Although time-specific aetiological influences emerged for each trait at ages 14 and 16 years, the aetiological factors involved in the association between ADHD symptoms and IQ were stable over time. ADHD symptoms and IQ scores significantly predicted each other over time. ADHD symptoms at age 12 years were a significantly stronger predictor of vocabulary and Raven’s scores at age 14 years than vice versa, whereas no differential predictive effects emerged from age 14 to 16 years. The results suggest that ADHD symptoms may put adolescents at risk for decreased IQ scores. Persistent genetic influences seem to underlie the association of ADHD symptoms and IQ over time. Early intervention is likely to be key to reducing ADHD symptoms and the associated risk for lower IQ.