Prenatal Exposure to Acetaminophen and Risk for Attention Deficit Hyperactivity Disorder and Autistic Spectrum Disorder: A Systematic Review, Meta-Analysis, and Meta-Regression Analysis of Cohort Studies

Cohort profile: longitudinal and population comparison of children who are HIV-exposed uninfected and children who are HIV unexposed in Kenya (HOPE study)

PURPOSE

Globally, the number of children/adolescents exposed to HIV but uninfected (HIV-exposed uninfected, HEU) is growing. The HEU outcomes: population-evaluation and screening strategies study was designed to provide population-level evidence of the impact of HIV and recent antiretroviral therapy regimen exposure on neurodevelopmental, hearing and mental health outcomes from infancy to adolescence.

PARTICIPANTS

The study includes a prospective mother-infant cohort and cross-sectional child/youth-caregiver cohorts conducted in Kenya.Between 2021 and 2022, the study enrolled 2000 mother-infant pairs (1000 HEU and 1000 HIV-unexposed uninfected (HUU)) for longitudinal follow-up. Infants were eligible if they were aged 4-10 weeks and healthy. Mothers were eligible if their HIV status was known and were ≥18 years. Study visits are 6 monthly until the child reaches age 3 years.Cross-sectional cohorts spanning ages 3-18 years started enrolment in 2022. Target enrolment is 4400 children/youth (4000 HEU and 400 HUU). Children and youth are eligible if they are HIV negative, maternal HIV status and timing of diagnosis is known, and caregivers are ≥18 years.Data on infant/child/youth growth, neurodevelopment, mental health, morbidity and hearing are collected at enrolment using standardised tools. Dry blood spots samples are collected for telomere length assessment at baseline and yearly for the longitudinal cohort. Growth z-scores, neurodevelopmental scores, telomere length and prevalence of developmental and hearing problems will be compared between HEU/HUU populations.

FINDINGS TO DATE

Full cohort enrolment for the longitudinal cohort is complete and participants are in follow-up. At 1 year of age, comparing HEU to HUU neurodevelopment using the Malawi developmental assessment tool, we found that HEU infants had higher language scores and comparable scores in fine motor, gross motor and social scores. The cross-sectional cohort has enrolled over 2000 participants and recruitment is ongoing.

FUTURE PLANS

Longitudinal cohort follow-up and enrolment to the cross-sectional study will be completed in June 2024.

Early childhood exposures to phthalates in association with attention-deficit/hyperactivity disorder behaviors in middle childhood and adolescence in the ReCHARGE study

BACKGROUND

Early-life exposure to phthalates alters behaviors in animals. However, epidemiological evidence on childhood phthalate exposure and attention-deficit/hyperactivity disorder (ADHD) behaviors is limited.

METHODS

This study included 243 children from the ReCHARGE (Revisiting Childhood Autism Risks from Genetics and Environment) study, who were previously classified as having autism spectrum disorder (ASD), developmental delay, other early concerns, and typical development in the CHARGE case-control study. Twenty phthalate metabolites were measured in spot urine samples collected from children aged 2-5 years. Parents reported on children's ADHD symptoms at ages 8-18 years using Conners-3 Parent Rating Scale. Covariate-adjusted negative binomial generalized linear models were used to investigate associations between individual phthalate metabolite concentrations and raw scores. Weighted quantile sum (WQS) regression with repeated holdout validation was used to examine mixture effects of phthalate metabolites on behavioral scores. Effect modification by child sex was evaluated.

RESULTS

Among 12 phthalate metabolites detected in >75% of the samples, higher mono-2-heptyl phthalate (MHPP) was associated with higher scores on Inattentive (β per doubling = 0.05, 95% confidence interval [CI]: 0.02, 0.08) and Hyperactive/Impulsive scales (β = 0.04, 95% CI: 0.00, 0.07), especially among children with ASD. Higher mono-carboxy isooctyl phthalate (MCiOP) was associated with higher Hyperactivity/Impulsivity scores (β = 0.07, 95% CI: -0.01, 0.15), especially among typically developing children. The associations of the molar sum of high molecular weight (HMW) phthalate metabolites and a phthalate metabolite mixture with Hyperactivity/Impulsivity scores were modified by sex, showing more pronounced adverse associations among females.

CONCLUSION

Exposure to phthalates during early childhood may impact ADHD behaviors in middle childhood and adolescence, particularly among females. Although our findings may not be broadly generalizable due to the diverse diagnostic profiles within our study population, our robust findings on sex-specific associations warrant further investigations.

Maternal and paternal licit and illicit drug use, smoking and drinking and autism spectrum disorder

The aim of this study was to investigate the association between maternal and paternal licit and illicit drug use, smoking and drinking and autism spectrum disorder (ASD). We conducted a case-control study with children and adolescents diagnosed with ASD and neurotypical individuals. The data were collected using a semi-structured questionnaire administered during interviews with the children's mothers or guardians. The following variables were analyzed: child sex and age; maternal and parental age; use of medicines before and during pregnancy; classes of medicines used during pregnancy; maternal and paternal smoking; maternal and paternal drinking; maternal and paternal illicit drug use. The data were analyzed using logistic regression and crude and adjusted odds ratios (OR). After adjustment, the results showed an association between maternal use of antipyretics/pain killers during pregnancy (OR = 2.26; 95%CI 1.29-3.95; p < 0.040) and ASD. No association was found between maternal and paternal smoking, drinking and illicit drug use before and during pregnancy and ASD. The findings suggest that the development of ASD is influenced by environmental factors.

Interaction between Per- and Polyfluorinated Substances (PFAS) and Acetaminophen in Disease Exacerbation-Focusing on Autism and the Gut-Liver-Brain Axis

This review presents a new perspective on the exacerbation of autism spectrum disorder (ASD) by per- and polyfluoroalkyl substances (PFAS) through the gut-liver-brain axis. We have summarized evidence reported on the involvement of the gut microbiome and liver inflammation that led to the onset and exacerbation of ASD symptoms. As PFAS are toxicants that particularly target liver, this review has comprehensively explored the possible interaction between PFAS and acetaminophen, another liver toxicant, as the chemicals of interest for future toxicology research. Our hypothesis is that, at acute dosages, acetaminophen has the ability to aggravate the impaired conditions of the PFAS-exposed liver, which would further exacerbate neurological symptoms such as lack of social communication and interest, and repetitive behaviors using mechanisms related to the gut-liver-brain axis. This review discusses their potential interactions in terms of the gut-liver-brain axis and signaling pathways that may contribute to neurological diseases.

The risk of attention-deficit hyperactivity disorder among children with congenital heart disease: A systematic review and meta-analysis

BACKGROUND

Although current treatments are effective in dealing with congenital heart disease (CHD), non-cardiac comorbidities such as attention-deficit hyperactivity disorder (ADHD) have received widespread attention. The purpose of this systematic review and meta-analysis is to assess the risk of ADHD associated with CHD.

METHODS

The literature search was carried out systematically through eight different databases by the end of September 2022. Either a fixed- or a random-effects model was used to calculate the overall combined risk estimates. The heterogeneity of the studies was assessed by the Cochran Q test and the I2 statistic. Subgroup and sensitivity analyses were used to explore the potential sources of heterogeneity.

RESULTS

Eleven studies were included in this study, which involved a total of 296 741 participants. Our study showed that the children with CHD were at a significantly increased risk of ADHD compared with the reference group (OR = 2.98, 95% CI: 2.18-4.08). The results were moderately heterogeneous. These factors including study design, geographic region and study quality were identified as the first three of the most relevant heterogeneity moderators by subgroup analyses. Sensitivity analysis yielded consistent results. There was no evidence of publication bias.

CONCLUSIONS

The present study suggests that CHD children have a significantly higher risk of ADHD when compared with those without CHD. Early identification and intervention of ADHD is important to reduce its symptoms and adverse effects; therefore, clinicians should increase screening for ADHD in children with CHD and intervene promptly to reduce its effects whenever possible.

Postnatal acetaminophen exposure and neurodevelopmental outcomes at 18-21 months corrected gestational age in preterm infants <29 weeks gestation: a retrospective cohort study

BACKGROUND

Studies have reported prenatal acetaminophen exposure is associated with abnormal neurodevelopment. There is limited and conflicting data on neurodevelopmental outcomes following postnatal acetaminophen exposure. Our objective was to investigate the neurodevelopmental outcomes of preterm infants < 29 weeks gestation postnatally exposed to acetaminophen.

METHODS

Retrospective cohort study of infants born between 2008 and 2017 at a tertiary care perinatal center. Exclusion criteria included chromosomal disorders, major congenital abnormalities, and congenital infections. The primary outcome was a composite score of <85 on the cognitive, language, or motor components of the Bayley Scales of Infant and Toddler Development, 3rd edition, assessed at 18 to 21 months corrected gestational age. Multivariate logistic regression was used to assess confounders.

RESULTS

Of the 945 infants included in the study, 120 were in the acetaminophen group. There was no difference in any of Bayley-III cognitive, language or motor composite scores of < 85 between the two groups for postnatal acetaminophen exposure, adjusted odds ratios (aORs) 1.03, 95% CI 0.60-1.78, or days of acetaminophen use, aORs 1.10, 95% CI 0.93-1.29.

CONCLUSIONS

There was no difference in neurodevelopmental outcome between the acetaminophen exposed and non-exposed groups. Our results need validation in larger cohorts.

IMPACT

Animal research and cohort studies have suggested that prenatal acetaminophen exposure may be associated with an elevated risk of neurobehavioral abnormalities. However, there is limited and conflicting research on the impact of postnatal acetaminophen on neurodevelopment. The results of this study suggest that postnatal acetaminophen does not negatively impact neurodevelopment at 18 to 21 months in preterm infants born at <29 weeks gestational age. While these results need validation in larger and more longitudinal studies, this study provides reassurance for the use of postnatal acetaminophen in extremely preterm infants.

Gestational paracetamol exposure induces core behaviors of neurodevelopmental disorders in infant rats and modifies response to a cannabinoid agonist in females

Paracetamol (PAR) is an over-the-counter analgesic/antipyretic used during pregnancy worldwide. Epidemiological studies have been associating gestational PAR exposure with neurobehavioral alterations in the progeny resembling autism spectrum disorders and attention-deficit hyperactivity disorder symptoms. The endocannabinoid (eCB) dysfunction was previously hypothesized as one of the modes of action by which PAR may harm the developing nervous system. We aimed to evaluate possible effects of gestational exposure to PAR on male and female rat's offspring behavior and if an acute injection of WIN 55,212-2 (WIN, 0.3 mg/kg), a non-specific cannabinoid agonist, prior to behavioral tests, would induce different effects in PAR exposed and non-exposed animals. Pregnant Wistar rats were gavaged with PAR (350 mg/kg/day) or water from gestational day 6 until delivery. Nest-seeking, open field, apomorphine-induced stereotypy, marble burying and three-chamber tests were conducted in 10-, 24-, 25- or 30-days-old rats, respectively. PAR exposure resulted in increased apomorphine-induced stereotyped behavior and time spent in the central area of the open field in exposed female pups. Additionally, it induced hyperactivity in the open field and increased marble burying behavior in both male and female pups. WIN injection modified the behavioral response only in the nest seeking test, and opposite effects were observed in control and PAR-exposed neonate females. Reported alterations are relevant for the neurodevelopmental disorders that have been associated with maternal PAR exposure and suggest that eCB dysfunction may play a role in the action by which PAR may harm the developing brain.

Maternal exposure to particulate matter early in pregnancy and congenital anomalies in offspring: Analysis of concentration-response relationships in a population-based cohort with follow-up throughout childhood

Studies have suggested an association between particulate matter (PM) air pollution and certain congenital anomalies (CAs). However, most studies assumed a linear concentration-response relation and were based on anomalies that were ascertained at birth or up to 1 year of age. We investigated associations between exposures to PM during the first trimester of pregnancy and CAs in 9 organ systems using birth and childhood follow-up data from a leading health care provider in Israel. We conducted a retrospective population-based cohort study among 396,334 births, 2004-2015. Daily PM data at a 1 × 1 km spatial grid were obtained from a satellite-derived prediction models and were linked to the mothers' residential addresses at birth. Adjusted odds ratios (ORs) were estimated with logistic regression models using exposure levels as either continuous or categorical variables. We captured 57,638 isolated CAs with estimated prevalence of 96 and 136 anomalies per 1000 births in the first year of life and by age 6 years, respectively. Analysis of continuous PM with diameter < 2.5 μm (PM_2.5) indicated a supra-linear relation with anomalies in the circulatory, respiratory, digestive, genital and integument systems (79 % of CAs). The slope of the concentration-response function was positive and steepest for PM_2.5 lower than the median concentration (21.5 μg/m³) and had a less steep or negative slope at higher levels. Similar trends were observed for PM_2.5 quartiles. For example, for cardiac anomalies, the ORs were 1.09 (95 % confidence interval: 1.02, 1.15), 1.04 (0.98, 1.10) and 1.00 (0.94, 1.07) for births in the second, third and fourth quartiles, respectively, when compared to the first quartile. In sum, this study adds new evidence for adverse effects of air pollution on neonatal health even with low-level air pollution. Information on late diagnosis of children with anomalies is important in evaluating the burden of disease.

Screening of attention deficit hyperactivity disorder among preschool children Gharbia Governorate, Egypt

BACKGROUND

Children who experience mental health issues, such as attention deficit hyperactivity disorder (ADHD), experience significant distress and impairment at home, at school, and in the community. Without adequate care or prevention, this frequently results in adulthood-long distress and impairment at large societal costs. Determining the prevalence of ADHD cases among preschoolers as well as some associated maternal and child risk factors was the aim of this study.

METHODS

An analytical cross-sectional study including 1048 preschool children aged 3-6 years was carried out in Tanta City, Gharbia Governorate. From March to April 2022, a proportionate stratified cluster random sample of them was picked. Data were gathered using a predesigned instrument that included sociodemographic information, family history, maternal and child risk factors, and the Arabic version of the ADHD Rating Scale IV questionnaire.

RESULTS

The prevalence of ADHD among preschoolers was 10.5%. The inattention type was the most common (5.3%), followed by the hyperactivity type (3.4%). There were statistically significant associations regarding positive family history of psychological and neurological symptoms (17.9% positive vs. 9.7% negative), family history of ADHD symptoms (24.5% positive vs. 9.4% negative), active smoking by the mother (21.1% positive vs. 5.3% negative), cesarean section delivery (66.4% positive vs. 53.9% negative), elevated blood pressure during pregnancy (19.1% positive vs. 12.4% negative), and history of taking drugs during pregnancy (43.6% positive vs. 31.7% negative). Significant child risk factors were: exposure to any source containing lead that causes slow poisoning (25.5% positive vs. 12.3% negative), children with cardiac health problems (38.2% positive vs. 16.6% negative), and hours spent by a child in front of the TV or mobile phone (any screens) per day (60.0% of those with positive screening spent more than 2 h/day vs. 45.7% negative).

CONCLUSION

In the Gharbia governorate, 10.5% of preschoolers suffer from ADHD. Significant maternal risk factors for ADHD included a positive family history of psychiatric and neurological symptoms, a family history of ADHD symptoms, active maternal smoking, caesarean section delivery, increased blood pressure during pregnancy, and a history of drug use during pregnancy. Youngsters who had cardiac health issues and who spent more time each day watching TV or using a mobile device (screen use) were at substantial risk.

Potential adverse actions of prenatal exposure of acetaminophen to offspring

Acetaminophen (APAP) is a widely used as analgesic and antipyretic drug. APAP is also added as an active ingredient in various medications to relieve pain and reduce fever. APAP has been widely used in pregnant women in the past decades because it is considered a relatively safe drug with recommended dose in different countries. However, an increasing number of epidemiological and experimental studies have shown that APAP exposure during pregnancy may increase the risk of inducing reproductive and neurobehavior dysfunctions, hepatotoxicity in offspring. This review aims to assess the potential effects of prenatal APAP exposure on offspring growth and development.

In utero acetaminophen exposure and child neurodevelopmental outcomes: Systematic review and meta-analysis

BACKGROUND

Acetaminophen is a frequently used analgesic for pain and fever. There have been reports of adverse neurodevelopmental outcomes associated with in utero acetaminophen exposure. However, it is unclear whether this association is related directly to acetaminophen use, or the reasons for use.

OBJECTIVES

To summarise the literature on the association between in utero acetaminophen exposure and child neurodevelopmental outcomes, and assess the extent to which the association is due to confounding by indication.

DATA SOURCES

OVID for Medline, Embase, and PsycINFO, and EBSCO for CINAHL, from inception to August 18, 2022.

STUDY SELECTION AND DATA EXTRACTION

We searched for peer-reviewed, English-language studies on in utero acetaminophen exposure and child neurodevelopmental outcomes. Data were extracted using a standardised form created a priori, and quality was assessed using the Systematic Assessment of Quality in Observational Research.

SYNTHESIS

We generated pooled risk ratios (RR) for outcomes examined by ≥3 studies using random-effects models; outcomes that could not be meta-analysed were narratively summarised following Synthesis Without Meta-Analysis guidelines.

RESULTS

Twenty-two studies including 23 cohorts were eligible (n = 367,775 total participants; median: 51.7% with acetaminophen exposure). Studies were primarily prospective cohort studies from Europe and the US, with attention deficit/hyperactivity disorder (ADHD) being the most common outcome. Quality assessments resulted in 13.6% of studies being classified as high, 59.1% as medium, 22.7% as low, and 4.5% as very low quality. In utero acetaminophen exposure was associated with an elevated risk of ADHD (unadjusted pooled RR 1.32, 95% confidence interval [CI] 1.20, 1.44; I²  = 47%, n = 7 studies), with little difference after adjusting for confounders, including indications for acetaminophen use (adjusted pooled RR 1.34, 95% CI 1.15, 1.55; I²  = 50%, n = 4 studies).

CONCLUSIONS

Confounding by indication did not explain the association between in utero acetaminophen exposure and child ADHD. Further, high-quality research is needed on this and other neurodevelopmental outcomes.

Safety of drugs used for the treatment of migraine during pregnancy: a narrative review

INTRODUCTION

Migraine is common in females of childbearing age and negatively impacts quality of life. The majority of those with migraine who become pregnant see an improvement in their condition but not all do. Providing evidence-based recommendations for the pharmacological management of migraine in pregnancy is challenging.

AREAS COVERED

This narrative review provides an update on the safety of drugs used for migraine in pregnancy. National and international guidelines on the management of episodic migraine in adults were used to select the drugs of relevance to pregnant women. The final list of drugs was chosen by a pain specialist who categorized them according to drug class and use in acute management or prevention. PubMed was searched from inception to 31st July 2022 for evidence on drug safety.

EXPERT OPINION

Obtaining high-quality drug safety data in pregnant migraineurs is difficult not least because exposing a fetus to research-related risks is often considered unethical. There is reliance on observational studies which often group drugs together and lack specificities pertinent to drug prescribing like timing, dosing and duration. Improved statistical tools, study designs and the creation of international collaborative frameworks are ways to advance knowledge on drug safety in pregnancy.

The safety of pediatric use of paracetamol (acetaminophen): a narrative review of direct and indirect evidence

Paracetamol (acetaminophen) use during pregnancy and early childhood was accepted as safe in the 1970s, but is now a subject of considerable concern. Careful analysis shows that initial acceptance of the drug was based on the false assumption that drug interactions in babies and adults are the same, and on a complete absence of knowledge regarding the impact of the drug on brain development. At least fourteen epidemiological studies now indicate that prenatal exposure to paracetamol is associated with neurodevelopmental problems. Based on these studies, it can be concluded that prenatal exposure to paracetamol causes statistically significant risks of developmental delays, attention deficit hyperactivity disorder, and a subtype of autism spectrum disorder (ASD) associated with hyperkinetic behavior. In contrast, data regarding postnatal exposure to paracetamol are limited, and several factors impede a classic multivariate analysis of epidemiologic data to resolve the issue. However, circumstantial evidence regarding postnatal exposure to the drug is abundant, and includes at least three otherwise unexplained temporal relationships, data from laboratory animal studies, several miscellaneous and otherwise unexplained correlations, and a lack of alternative suspects that fit the evidence-derived profile. Based on this evidence, it can be concluded without any reasonable doubt that oxidative stress puts some babies and children at risk of paracetamol-induced neurodevelopmental injury, and that postnatal exposure to paracetamol in those susceptible babies and children is responsible for many if not most cases of ASD.

Maternal use of acetaminophen during pregnancy and neurobehavioral problems in offspring at 3 years: A prospective cohort study

Background

Acetaminophen is one of the most commonly used drugs during pregnancy globally. Recent studies have reported associations between prenatal exposure to acetaminophen and neurobehavioral problems in children, including attention-deficit hyperactivity disorders. Little research has investigated these associations in preschool-age children or the potential confounding effects of prenatal stress. The purpose of this study was to examine associations between prenatal acetaminophen exposure and offspring neurobehavioral problems at the age of 3 years, with a focus on the potentially confounding effects of prenatal stress.

Methods

We used data from the First Baby Study, a prospective cohort study conducted in Pennsylvania, USA, with 2,423 mother-child pairs. Women reported medication use and completed a prenatal stress inventory during their third trimester. Child behavioral problems were measured at the age of 3 years, using the 7 syndrome scale scores from the Child Behavior Checklist (CBCL) for ages 1 ½ to 5.

Results

There were 1,011 women (41.7%) who reported using acetaminophen during pregnancy. Children who were exposed to acetaminophen during pregnancy scored significantly higher on 3 of the 7 CBCL syndrome scales: withdrawn, sleep problems and attention problems. Scores on all 7 of the CBCL syndrome scales were significantly associated with prenatal stress. After adjustment for prenatal stress and other confounders, 2 syndrome scales remained significantly higher in children exposed to acetaminophen: sleep problems (aOR = 1.23, 95% CI = 1.01–1.51) and attention problems (aOR = 1.21, 95% CI = 1.01–1.45).

Conclusions

These findings corroborate previous studies reporting associations between prenatal exposure to acetaminophen and attention problems in offspring and also show an association with sleep problems at age 3 years. Because use of acetaminophen during pregnancy is common, these results are of public health concern and suggest caution in the use of medications containing acetaminophen during pregnancy.

Interleukin-1β-induced inflammation and acetaminophen during infancy: Distinct and interactive effects on social-emotional and repetitive behavior in C57BL/6J mice

Acetaminophen (APAP) exposure early in life has been associated with increased risk of neurodevelopmental disorders in epidemiological studies. In rodent models, early-life APAP has similarly been shown to produce long-term changes in brain and behavior, including altered activity levels and social behavior. Most rodent studies to date have, nevertheless, attempted to model early-life APAP without considering that most APAP exposure occurs in a context of immune activation and/or fever. To mimic the repeated infections common during infancy, we employed the cytokine interleukin-1β (IL-1β) to induce immune activation three times during early postnatal development (i.e., day 5, 8, and 11). On these days, C57BL/6J pups were administered either IL-1β (0.2 μg/kg) or saline vehicle followed, after 45 min, by either APAP (103.9 mg/kg) or vehicle. Mice were subsequently administered a battery of tests of social-emotional and repetitive behavior. A number of distinct long-term effects of IL-1β and APAP treatments were found, including sex-specific shifts in repetitive behavior and emotional hyperthermia following early-life IL-1β and increased social caution in males following early-life APAP. We also observed significant interaction between IL-1β and APAP: as adults, 'two-hit' IL-1β + APAP females displayed greater anxiety-related thigmotaxis across a number of tests, including an open field. 'Two hit' males, in turn, showed elevated levels of avoidance of an unfamiliar social partner during a social interaction test. Our results highlight that IL-1β-induced inflammation and APAP have both distinct effects and significant interactions during early life, with enduring sex-specific effects on phenotypes relevant to neurodevelopmental disorders.

Prenatal risk factors and genetic causes of ADHD in children

BACKGROUND

Attention deficit/hyperactivity disorder (ADHD) is a common disease among children; it affected 5-7% of the population in 2015. ADHD is a multifactorial disease, and its etiology is still not clearly understood.

DATA SOURCES

This narrative review has been done by searching the PubMed and Embase databases using attention deficit/hyperactivity disorder, ADHD, risk factors; genetics; pediatrics; psychiatrics as keywords.

RESULTS

ADHD is considered to be a hereditary disorder in which genes play the fundamental role in the pathogenesis; however, findings from genetic-environmental studies support the hypothesis that genetic factors can exert effects on an individual's condition by determining his/her responses to environmental exposures, especially those during the prenatal stage.

CONCLUSION

ADHD is considered as a hereditary disorder in which genes and prenatal risk factors play fundamental roles in the pathogenesis.

Analgesic drug use in pregnancy and neurodevelopment outcomes: an umbrella review

Emerging evidence from reviews suggests that analgesic drug exposure during pregnancy may contribute to child neurodevelopment outcomes. A comprehensive overview of existing evidence is needed for firm conclusions to inform clinical guidelines. This umbrella review aims to synthesise high-quality evidence on prenatal analgesic drug exposure and risk of ASD and ADHD in children. Seven databases were searched from inception to May 2021 to identify relevant reviews of any design. The AMSTAR 2 and the GRADE quality assessments were used to evaluate risk of bias and heterogeneity. A narrative synthesis approach was used to summarise findings. Five systematic reviews and meta-analyses met the inclusion criteria. All reviews reported significant associations between maternal prenatal acetaminophen use and ADHD outcomes (risk ratio range: 1.08-1.34; no pooled incidence rate), with a potential dose-dependent relationship. Potential sources of heterogeneity included usage timing and dosage. Findings suggest minimisation of prenatal acetaminophen exposure due to risk for ADHD outcomes. Future studies should include assessing potentially interacting mechanisms associating acetaminophen use with future neurodevelopmental outcomes.

Association of Prenatal Acetaminophen Exposure Measured in Meconium With Adverse Birth Outcomes in a Canadian Birth Cohort

BACKGROUND

The small number of studies examining the association of prenatal acetaminophen with birth outcomes have all relied on maternal self-report. It remains unknown whether prenatal acetaminophen exposure measured in a biological specimen is associated with birth outcomes.

OBJECTIVES

To investigate the association of acetaminophen measured in meconium with birthweight, gestational age, preterm birth, size for gestational age, gestational diabetes, preeclampsia, and high blood pressure.

METHODS

This birth cohort from Sherbrooke, QC, Canada, included 773 live births. Mothers with no thyroid disease enrolled at their first prenatal care visit or delivery. Acetaminophen was measured in meconium for 393 children at delivery. We tested associations of prenatal acetaminophen with birthweight, preterm birth, gestational age, small and large for gestational age, gestational diabetes, preeclampsia, and high blood pressure. We imputed missing data via multiple imputation and used inverse probability weighting to account for confounding and selection bias.

RESULTS

Acetaminophen was detected in 222 meconium samples (56.5%). Prenatal acetaminophen exposure was associated with decreased birthweight by 136 g (β = -136; 95% CI [-229, -43]), 20% increased weekly hazard of delivery (hazard ratio = 1.20; 95% CI [1.00, 1.43]), and over 60% decreased odds of being born large for gestational age (odds ratio = 0.38; 95% CI [0.20, 0.75]). Prenatal acetaminophen was not associated with small for gestational age, preterm birth, or any pregnancy complications.

CONCLUSION

Prenatal acetaminophen was associated with adverse birth outcomes. Although unobserved confounding and confounding by indication are possible, these results warrant further investigation into adverse perinatal effects of prenatal acetaminophen exposure.

Environmental exposures associated with elevated risk for autism spectrum disorder may augment the burden of deleterious de novo mutations among probands

Although the full aetiology of autism spectrum disorder (ASD) is unknown, familial and twin studies demonstrate high heritability of 60-90%, indicating a predominant role of genetics in the development of the disorder. The genetic architecture of ASD consists of a complex array of rare and common variants of all classes of genetic variation usually acting additively to augment individual risk. The relative contribution of heredity in ASD persists despite selective pressures against the classic autistic phenotype; a phenomenon thought to be explained, in part, by the incidence of spontaneous (or de novo) mutations. Notably, environmental exposures attributed as salient risk factors for ASD may play a causal role in the emergence of deleterious de novo variations, with several ASD-associated agents having significant mutagenic potential. To explore this hypothesis, this review article assesses published epidemiological data with evidence derived from assays of mutagenicity, both in vivo and in vitro, to determine the likely role such agents may play in augmenting the genetic liability in ASD. Broadly, these exposures were observed to elicit genomic alterations through one or a combination of: (1) direct interaction with genetic material; (2) impaired DNA repair; or (3) oxidative DNA damage. However, the direct contribution of these factors to the ASD phenotype cannot be determined without further analysis. The development of comprehensive prospective birth cohorts in combination with genome sequencing is essential to forming a causal, mechanistic account of de novo mutations in ASD that links exposure, genotypic alterations, and phenotypic consequences.

Paracetamol use during pregnancy - a call for precautionary action

Paracetamol (N-acetyl-p-aminophenol (APAP), otherwise known as acetaminophen) is the active ingredient in more than 600 medications used to relieve mild to moderate pain and reduce fever. APAP is widely used by pregnant women as governmental agencies, including the FDA and EMA, have long considered APAP appropriate for use during pregnancy when used as directed. However, increasing experimental and epidemiological research suggests that prenatal exposure to APAP might alter fetal development, which could increase the risks of some neurodevelopmental, reproductive and urogenital disorders. Here we summarize this evidence and call for precautionary action through a focused research effort and by increasing awareness among health professionals and pregnant women. APAP is an important medication and alternatives for treatment of high fever and severe pain are limited. We recommend that pregnant women should be cautioned at the beginning of pregnancy to: forego APAP unless its use is medically indicated; consult with a physician or pharmacist if they are uncertain whether use is indicated and before using on a long-term basis; and minimize exposure by using the lowest effective dose for the shortest possible time. We suggest specific actions to implement these recommendations. This Consensus Statement reflects our concerns and is currently supported by 91 scientists, clinicians and public health professionals from across the globe.

Paracetamol (Acetaminophen) and the Developing Brain

Paracetamol is commonly used to treat fever and pain in pregnant women, but there are growing concerns that this may cause attention deficit hyperactivity disorder and autism spectrum disorder in the offspring. A growing number of epidemiological studies suggests that relative risks for these disorders increase by an average of about 25% following intrauterine paracetamol exposure. The data analyzed point to a dose-effect relationship but cannot fully account for unmeasured confounders, notably indication and genetic transmission. Only few experimental investigations have addressed this issue. Altered behavior has been demonstrated in offspring of paracetamol-gavaged pregnant rats, and paracetamol given at or prior to day 10 of life to newborn mice resulted in altered locomotor activity in response to a novel home environment in adulthood and blunted the analgesic effect of paracetamol given to adult animals. The molecular mechanisms that might mediate these effects are unknown. Paracetamol has diverse pharmacologic actions. It reduces prostaglandin formation via competitive inhibition of the peroxidase moiety of prostaglandin H2 synthase, while its metabolite N-arachidonoyl-phenolamine activates transient vanilloid-subtype 1 receptors and interferes with cannabinoid receptor signaling. The metabolite N-acetyl-p-benzo-quinone-imine, which is pivotal for liver damage after overdosing, exerts oxidative stress and depletes glutathione in the brain already at dosages below the hepatic toxicity threshold. Given the widespread use of paracetamol during pregnancy and the lack of safe alternatives, its impact on the developing brain deserves further investigation.

Prenatal and postnatal exposure to acetaminophen in relation to autism spectrum and attention-deficit and hyperactivity symptoms in childhood: Meta-analysis in six European population-based cohorts

The potential etiological role of early acetaminophen exposure on Autism Spectrum Conditions (ASC) and Attention-Deficit/Hyperactivity Disorder (ADHD) is inconclusive. We aimed to study this association in a collaborative study of six European population-based birth/child cohorts. A total of 73,881 mother-child pairs were included in the study. Prenatal and postnatal (up to 18 months) acetaminophen exposure was assessed through maternal questionnaires or interviews. ASC and ADHD symptoms were assessed at 4-12 years of age using validated instruments. Children were classified as having borderline/clinical symptoms using recommended cutoffs for each instrument. Hospital diagnoses were also available in one cohort. Analyses were adjusted for child and maternal characteristics along with indications for acetaminophen use. Adjusted cohort-specific effect estimates were combined using random-effects meta-analysis. The proportion of children having borderline/clinical symptoms ranged between 0.9 and 12.9% for ASC and between 1.2 and 12.2% for ADHD. Results indicated that children prenatally exposed to acetaminophen were 19% and 21% more likely to subsequently have borderline or clinical ASC (OR = 1.19, 95% CI 1.07-1.33) and ADHD symptoms (OR = 1.21, 95% CI 1.07-1.36) compared to non-exposed children. Boys and girls showed higher odds for ASC and ADHD symptoms after prenatal exposure, though these associations were slightly stronger among boys. Postnatal exposure to acetaminophen was not associated with ASC or ADHD symptoms. These results replicate previous work and support providing clear information to pregnant women and their partners about potential long-term risks of acetaminophen use.

Perinatal Acetaminophen Exposure and Childhood Attention-Deficit/Hyperactivity Disorder (ADHD): Exploring the Role of Umbilical Cord Plasma Metabolites in Oxidative Stress Pathways

Oxidative stress mechanisms may explain associations between perinatal acetaminophen exposure and childhood attention-deficit hyperactivity disorder (ADHD). We investigated whether the changes in umbilical cord plasma amino acids needed to synthesize the antioxidant glutathione and in the oxidative stress biomarker 8-hydroxy-deoxyguanosine may explain the association between cord plasma acetaminophen and ADHD in the Boston Birth Cohort (BBC). Mother–child dyads were followed at the Boston Medical Center between 1998 and 2018. Cord plasma analytes were measured from archived samples collected at birth. Physician diagnoses of childhood ADHD were obtained from medical records. The final sample consisted of 568 participants (child mean age [SD]: 9.3 [3.5] years, 315 (52.8%) male, 248 (43.7%) ADHD, 320 (56.3%) neurotypical development). Cord unmetabolized acetaminophen was positively correlated with methionine (R = 0.33, p < 0.001), serine (R = 0.30, p < 0.001), glycine (R = 0.34, p < 0.001), and glutamate (R = 0.16, p < 0.001). Children with cord acetaminophen levels >50th percentile appeared to have higher risk of ADHD for each increase in cord 8-hydroxy-deoxyguanosine level. Adjusting for covariates, increasing cord methionine, glycine, serine, and 8-hydroxy-deoxyguanosine were associated with significantly higher odds for childhood ADHD. Cord methionine statistically mediated 22.1% (natural indirect effect logOR = 0.167, SE = 0.071, p = 0.019) and glycine mediated 22.0% (natural indirect effect logOR = 0.166, SE = 0.078, p = 0.032) of the association between cord acetaminophen >50th percentile with ADHD. Our findings provide some clues, but additional investigation into oxidative stress pathways and the association of acetaminophen exposure and childhood ADHD is warranted.

Behavioral Problems at Age 11 Years After Prenatal and Postnatal Exposure to Acetaminophen: Parent-Reported and Self-Reported Outcomes

Several studies have reported associations between prenatal acetaminophen exposure and behavioral outcomes in young children. We aimed to evaluate the associations of prenatal and postnatal exposures to acetaminophen with behavioral problems in children at age 11 years, using behavioral measures reported by parents and children. We studied 40,934 mother-child pairs from the Danish National Birth Cohort enrolled during 1996-2002. Parent-reported and child-reported Strengths and Difficulties Questionnaire (SDQ) responses were collected during the 11-year follow-up. We estimated risk ratios for behavioral problems including total difficulties as well as internalizing or externalizing behaviors following prenatal (during pregnancy) or postnatal (within the first 18 months after birth) acetaminophen exposure. Parent-reported and child-reported SDQ scores were moderately correlated; higher for externalizing (r = 0.59) than internalizing (r = 0.49) behaviors. Prenatal acetaminophen exposure was associated with 10%-40% higher risks for total difficulties and internalizing and externalizing problems based on parent- or child-reported SDQ, with the association being stronger for greater cumulative weeks of acetaminophen use. Postnatal exposure was associated with 16%-19% higher risks for parent-reported internalizing behaviors, but the associations were weak or null for child-reported scores except for prosocial behavior. Our study corroborates published associations between prenatal exposures to acetaminophen and behavioral problems and extends the literature to early adolescence.

Prenatal exposure to non-steroidal anti-inflammatory drugs and risk of attention-deficit/hyperactivity disorder: A follow-up study in the Norwegian mother, father and child cohort

PURPOSE

To estimate the association between Attention-Deficit/Hyperactivity Disorder (ADHD) in children in preschool and primary school, and prenatal exposure to non-steroidal anti-inflammatory drugs (NSAIDs) by timing and duration.

METHODS

This study was based on the Norwegian Mother, Father and Child Cohort Study linked to the Medical Birth Registry of Norway, the Norwegian Patient Registry (NPR) and the Norwegian Prescription Database (NorPD). NSAID exposure was identified by maternal self-report in pregnancy. Child diagnosis of ADHD was obtained from NPR and NorPD. Symptoms of ADHD at age 5 years were measured using Conners' Parent Rating Scale-Revised, where higher scores correspond to more symptoms. To account for time-varying exposure and confounders, marginal structural models were fitted to estimate hazard ratios and mean difference in z-scores.

RESULTS

The analyses on ADHD diagnosis and ADHD symptoms included 56 340 and 34 961 children respectively. Children exposed to NSAIDs prenatally had no increased risk of ADHD diagnosis (first trimester: HR 1.12, 95% CI 0.86;1.45, second trimester: HR 0.98, 95% CI 0.69;1.38, third trimester: HR 0.68, 95% CI 0.31; 1.46) or ADHD symptoms (first trimester: standardized mean difference 0.03, 95% CI -0.03;0.09, second trimester: standardized mean difference 0.03, 95% CI -0.04;0.11, third trimester: standardized mean difference 0.11, 95% CI -0.03; 0.25). There was no duration-response relationship for either outcome.

CONCLUSION

Though non-differential misclassification of the exposure may have attenuated results, these findings are reassuring and suggest no substantially increased risk of ADHD diagnosis or symptoms in children prenatally exposed to NSAIDs, regardless of timing or duration.

Perinatal exposure to paracetamol: Dose and sex-dependent effects in behaviour and brain's oxidative stress markers in progeny

Paracetamol (PAR) has been employed worldwide for pain and fever treatment during pregnancy and lactation. Epidemiologic studies have shown that exposure to PAR can increase the risk for developmental disorders, such as attention-deficit hyperactive disorder and autism spectrum disorder. This study aimed to investigate if gestational and lactational exposure to human-relevant doses of PAR could alter behavioural and brain oxidative stress parameters in the rat`s offspring. Wistar dams were gavaged daily with water or PAR (35 mg/kg/ or 350 mg/kg) during gestational day 6 to weaning (postnatal day 21). Behavioural assessments occurred at post-natal days 10 (nest seeking test), 27 (behavioural stereotypy) and 28 (three chamber sociability test and open field). Concentration of advanced oxidation protein products (AOPP), reduced glutathione (GSH), lipid hydroperoxides (LOOH) and activity of superoxide dismutase (SOD) were estimate in prefrontal cortex, hippocampus, striatum and cerebellum of 22-day-old rats. Compared to CON animals, males exposed to PAR during pregnancy and lactation augmented apomorphine-induced stereotyped behaviour (350 mg/kg) and ambulation in open-field test (35 mg/kg). Reduced exploratory behaviour in three chamber sociability test was observed in pups exposed to PAR at 350 mg/kg in both sexes. PAR treatment decreased hippocampal GSH level and striatal SOD activity in males exposed to 35 mg/kg, suggesting the vulnerability of these areas in PAR-induced developmental neurotoxicity. Findings suggest PAR use during pregnancy and lactation as a potential risk factor for neurodevelopmental disorders with males being more susceptible.

Early exposure to paracetamol reduces level of testicular testosterone and changes gonadal expression of genes relevant for steroidogenesis in rats offspring

In this study, we investigated the effects of early paracetamol treatment on the testicular level of testosterone and expression of genes important for steroid biosynthesis and reproduction in male rats offspring. Rats were continuously exposed to paracetamol at doses of 5 or 15 mg/kg b.w. during pregnancy and the first two months of the postpartum development. Testosterone level was determined by ELISA. Profile of gene expression for the testicular steroidogenic factors were evaluated using the Real-Time PCR. Our results showed that paracetamol reduces testicular testosterone level and causes compensatory transactivation of genes important for steroidogenesis and reproductive capacity. We have observed significant over-expression of several genes involved in cholesterol transport and steroid biosynthesis e.g., genes for steroidogenic acute regulatory protein, hydroxysteroid dehydrogenases, luteinizing hormone subunit beta, gonadotropin and androgen receptors. Up-regulation of these genes with parallel testosterone reduction in the testicles could be the possible mechanism that maintains and prevents the loss of the steroidogenic function.

Coronavirus Disease 2019 (COVID-19) Vaccines and Pregnancy: What Obstetricians Need to Know

Obstetricians will need to use the limited available data to guide their pregnant patients regarding benefits and risks of coronavirus disease 2019 (COVID-19) vaccination.

Coronavirus disease 2019 (COVID-19) vaccines have begun to be distributed across the United States and to be offered initially to priority groups including health care personnel and persons living in long-term care facilities. Guidance regarding whether pregnant persons should receive a COVID-19 vaccine is needed. Because pregnant persons were excluded from the initial phase 3 clinical trials of COVID-19 vaccines, limited data are available on their efficacy and safety during pregnancy. After developmental and reproductive toxicology studies are completed, some companies are expected to conduct clinical trials in pregnant persons. Until then, pregnant persons and their obstetricians will need to use available data to weigh the benefits and risks of COVID-19 vaccines. Issues to be considered when counseling pregnant persons include data from animal studies and inadvertently exposed pregnancies during vaccine clinical trials when available, potential risks to pregnancy of vaccine reactogenicity, timing of vaccination during pregnancy, evidence for safety of other vaccines during pregnancy, risk of COVID-19 complications due to pregnancy and the pregnant person's underlying conditions, and risk of exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and potential for risk mitigation. The Centers for Disease Control and Prevention, the American College of Obstetricians and Gynecologists, and the Society for Maternal-Fetal Medicine have each issued guidance supportive of offering COVID-19 vaccine to pregnant persons. As additional information from clinical trials and from data collected on vaccinated pregnant persons becomes available, it will be critical for obstetricians to keep up to date with this information.

Fetal and lactational exposure to the no-observed-adverse-effect level (NOAEL) dose of the neonicotinoid pesticide clothianidin inhibits neurogenesis and induces different behavioral abnormalities at the developmental stages in male mice

Recently, it has been reported that neonicotinoid pesticides (NNs) are transferred from mother to child and are assumed to affect the next generation, but the behavioral effects of NN exposure at different developmental stages have not been investigated. We exposed mice to no-observed-adverse-effect level (NOAEL) doses of clothianidin (CLO) during the fetal and lactational period, and then evaluated the neurobehavioral effects in juvenile and adult mice. Significant increases in anxiety-like behavior and locomotor activity were observed in juveniles and adults, respectively, and neuronal activity and neurogenesis in the hippocampal dentate gyrus were affected in both stages. These results suggest that fetal and lactational exposure to CLO may inhibit neurogenesis and cause different behavioral abnormalities at different developmental stages.

Acetaminophen Attenuates invasion and alters the expression of extracellular matrix enzymes and vascular factors in human first trimester trophoblast cells

Acetaminophen is one of the most common medications taken during pregnancy, considered safe for maternal health and fetal development. However, recent epidemiological studies have associated prenatal acetaminophen use with several developmental disorders in offspring. As acetaminophen can freely cross into and through the placenta, epidemiological associations with prenatal acetaminophen use may reflect direct actions on the fetus and/or the impact of altered placental functions. In the absence of rigorous mechanistic studies, our understanding of how prenatal acetaminophen exposure can cause long-term effects in offspring is limited. The objective of this study was to determine whether acetaminophen can alter key functions of a major placental cell type by utilizing immortalized human first trimester trophoblast cells. This study employed a comparative analysis with the nonsteroidal, anti-inflammatory drug aspirin, which has established effects in first trimester trophoblast cells. We report that immortalized trophoblast cells express the target proteins of acetaminophen and aspirin: cyclooxygenase (COX) -1 and -2. Unlike aspirin, acetaminophen significantly repressed the expression of angiogenesis and vascular remodeling genes in HTR-8/SVneo cells. Moreover, acetaminophen impaired trophoblast invasion by over 80%, while aspirin had no effect on invasion. Acetaminophen exposure reduced the expression of matrix metalloproteinase (MMP)-2 and -9 and increased the expression of tissue inhibitors of matrix metalloproteinases 2, leading to an imbalance in the ratio of proteolytic enzymes. Finally, a bioinformatic approach identified novel acetaminophen-responsive gene networks associated with key trophoblast functions and disease. Together these results suggest that prenatal acetaminophen use may interfere with critical trophoblast functions early in gestation, which may subsequently impact fetal development.

Management of primary headaches during pregnancy, postpartum, and breastfeeding: A systematic review

BACKGROUND

Primary headaches (migraine, tension headache, cluster headache, and other trigeminal autonomic cephalgias) are common in pregnancy and postpartum. It is unclear how to best and most safely manage them.

OBJECTIVE

We conducted a systematic review (SR) of interventions to prevent or treat primary headaches in women who are pregnant, attempting to become pregnant, postpartum, or breastfeeding.

METHODS

We searched Medline, Embase, Cochrane CENTRAL, CINAHL, ClinicalTrials.gov, Cochrane Database of SRs, and Epistemonikos for primary studies of pregnant women with primary headache and existing SRs of harms in pregnant women regardless of indication. No date or language restrictions were applied. We assessed strength of evidence (SoE) using standard methods.

RESULTS

We screened 8549 citations for studies and 2788 citations for SRs. Sixteen studies (mostly high risk of bias) comprising 14,185 patients (total) and 26 SRs met the criteria. For prevention, we found no evidence addressing effectiveness. Antiepileptics, venlafaxine, tricyclic antidepressants, benzodiazepines, β-blockers, prednisolone, and oral magnesium may be associated with fetal/child adverse effects, but calcium channel blockers and antihistamines may not be (1 single-group study and 11 SRs; low-to-moderate SoE). For treatment, combination metoclopramide and diphenhydramine may be more effective than codeine for migraine or tension headache (1 randomized controlled trial; low SoE). Triptans may not be associated with fetal/child adverse effects (8 nonrandomized comparative studies; low SoE). Acetaminophen, prednisolone, indomethacin, ondansetron, antipsychotics, and intravenous magnesium may be associated with fetal/child adverse effects, but low-dose aspirin may not be (indirect evidence; low-to-moderate SoE). We found insufficient evidence regarding non-pharmacologic treatments.

CONCLUSIONS

For prevention of primary headache, calcium channel blockers and antihistamines may not be associated with fetal/child adverse effects. For treatment, combination metoclopramide and diphenhydramine may be more effective than codeine. Triptans and low-dose aspirin may not be associated with fetal/child adverse effects. Future research should identify effective and safe interventions in pregnancy and postpartum.

Intrauterine Exposure to Acetaminophen and Adverse Developmental Outcomes: Epidemiological Findings and Methodological Issues

PURPOSE OF REVIEW

Acetaminophen (or paracetamol) is one of the most commonly used medications during pregnancy. We reviewed recent epidemiological evidence regarding intrauterine exposure to acetaminophen and risk for asthma, neurodevelopment disorders, and reproductive health in childhood.

RECENT FINDINGS

An increasing number of cohort studies have suggested that maternal use of acetaminophen during pregnancy was associated with increased risk for asthma; neurodevelopmental disorders, especially ADHD and behavioral problems; and genital malformations in the offspring. Oxidative stress and inflammation or endocrine effects are plausible shared biological mechanisms for the exposure to influence multiple developmental outcomes. We discussed methodological challenges that can threaten the validity of these observational data, including confounding and measurement errors. Novel statistical methods and research designs that can be used to mitigate these issues were introduced. Given the high prevalence of use, findings regarding intrauterine exposure to acetaminophen on multiple child health outcomes raise concerns. Research on causal and non-causal mechanisms that might explain these associations should be a priority.

Association of Prenatal Acetaminophen Exposure Measured in Meconium With Risk of Attention-Deficit/Hyperactivity Disorder Mediated by Frontoparietal Network Brain Connectivity

Importance

Despite evidence of an association between prenatal acetaminophen exposure and attention-deficit/hyperactivity disorder (ADHD) in offspring, the drug is not contraindicated during pregnancy, possibly because prior studies have relied on maternal self-report, failed to quantify acetaminophen dose, and lacked mechanistic insight.

Objective

To examine the association between prenatal acetaminophen exposure measured in meconium (hereinafter referred to as meconium acetaminophen) and ADHD in children aged 6 to 7 years, along with the potential for mediation by functional brain connectivity.

Design, Setting, and Participants

This prospective birth cohort study from the Centre Hospitalier Université de Sherbrooke in Sherbrooke, Québec, Canada, included 394 eligible children, of whom 345 had meconium samples collected at delivery and information on ADHD diagnosis. Mothers were enrolled from September 25, 2007, to September 10, 2009, at their first prenatal care visit or delivery and were followed up when children were aged 6 to 7 years. When children were aged 9 to 11 years, resting-state brain connectivity was assessed with magnetic resonance imaging. Data for the present study were collected from September 25, 2007, to January 18, 2020, and analyzed from January 7, 2019, to January 22, 2020.

Exposures

Acetaminophen levels measured in meconium.

Main Outcomes and Measures

Physician diagnosis of ADHD was determined at follow-up when children were aged 6 to 7 years or from medical records. Resting-state brain connectivity was assessed with magnetic resonance imaging; attention problems and hyperactivity were assessed with the Behavioral Assessment System for Children Parent Report Scale. Associations between meconium acetaminophen levels and outcomes were estimated with linear and logistic regressions weighted on the inverse probability of treatment to account for potential confounders. Causal mediation analysis was used to test for mediation of the association between prenatal acetaminophen exposure and hyperactivity by resting-state brain connectivity.

Results

Among the 345 children included in the analysis (177 boys [51.3%]; mean [SD] age, 6.58 [0.54] years), acetaminophen was detected in 199 meconium samples (57.7%), and ADHD was diagnosed in 33 children (9.6%). Compared with no acetaminophen, detection of acetaminophen in meconium was associated with increased odds of ADHD (odds ratio [OR], 2.43; 95% CI, 1.41-4.21). A dose-response association was detected; each doubling of exposure increased the odds of ADHD by 10% (OR, 1.10; 95% CI, 1.02-1.19). Children with acetaminophen detected in meconium showed increased negative connectivity between frontoparietal and default mode network nodes to clusters in the sensorimotor cortices, which mediated an indirect effect on increased child hyperactivity (14%; 95% CI, 1%-26%).

Conclusions and Relevance

Together with the multitude of other cohort studies showing adverse neurodevelopment associated with prenatal acetaminophen exposure, this work suggests caution should be used in administering acetaminophen during pregnancy. Research into alternative pain management strategies for pregnant women could be beneficial.

Environmental risk factors, protective factors, and peripheral biomarkers for ADHD: an umbrella review

BACKGROUND

Many potential environmental risk factors, environmental protective factors, and peripheral biomarkers for ADHD have been investigated, but the consistency and magnitude of their effects are unclear. We aimed to systematically appraise the published evidence of association between potential risk factors, protective factors, or peripheral biomarkers, and ADHD.

METHODS

In this umbrella review of meta-analyses, we searched PubMed including MEDLINE, Embase, and the Cochrane Database of Systematic Reviews, from database inception to Oct 31, 2019, and screened the references of relevant articles. We included systematic reviews that provided meta-analyses of observational studies that examined associations of potential environmental risk factors, environmental protective factors, or peripheral biomarkers with diagnosis of ADHD. We included meta-analyses that used categorical ADHD diagnosis criteria according to DSM, hyperkinetic disorder according to ICD, or criteria that were less rigorous than DSM or ICD, such as self-report. We excluded articles that did not examine environmental risk factors, environmental protective factors, or peripheral biomarkers of ADHD; articles that did not include a meta-analysis; and articles that did not present enough data for re-analysis. We excluded non-human studies, primary studies, genetic studies, and conference abstracts. We calculated summary effect estimates (odds ratio [OR], relative risk [RR], weighted mean difference [WMD], Cohen's d, and Hedges' g), 95% CI, heterogeneity I² statistic, 95% prediction interval, small study effects, and excess significance biases. We did analyses under credibility ceilings, and assessed the quality of the meta-analyses with AMSTAR 2 (A Measurement Tool to Assess Systematic Reviews 2). This study is registered with PROSPERO, number CRD42019145032.

FINDINGS

We identified 1839 articles, of which 35 were eligible for inclusion. These 35 articles yielded 63 meta-analyses encompassing 40 environmental risk factors and environmental protective factors (median cases 16 850, median population 91 954) and 23 peripheral biomarkers (median cases 175, median controls 187). Evidence of association was convincing (class I) for maternal pre-pregnancy obesity (OR 1·63, 95% CI 1·49 to 1·77), childhood eczema (1·31, 1·20 to 1·44), hypertensive disorders during pregnancy (1·29, 1·22 to 1·36), pre-eclampsia (1·28, 1·21 to 1·35), and maternal acetaminophen exposure during pregnancy (RR 1·25, 95% CI 1·17 to 1·34). Evidence of association was highly suggestive (class II) for maternal smoking during pregnancy (OR 1·6, 95% CI 1·45 to 1·76), childhood asthma (1·51, 1·4 to 1·63), maternal pre-pregnancy overweight (1·28, 1·21 to 1·35), and serum vitamin D (WMD -6·93, 95% CI -9·34 to -4·51).

INTERPRETATION

Maternal pre-pregnancy obesity and overweight; pre-eclampsia, hypertension, acetaminophen exposure, and smoking during pregnancy; and childhood atopic diseases were strongly associated with ADHD. Previous familial studies suggest that maternal pre-pregnancy obesity, overweight, and smoking during pregnancy are confounded by familial or genetic factors, and further high-quality studies are therefore required to establish causality.

FUNDING

None.

Over-the-counter analgesics during pregnancy: a comprehensive review of global prevalence and offspring safety

BACKGROUND

Analgesia during pregnancy is often necessary. Due to their widespread availability, many mothers opt to use over-the-counter (OTC) analgesics. Those analgesic compounds and their metabolites can readily cross the placenta and reach the developing foetus. Evidence for safety or associations with adverse health outcomes is conflicting, limiting definitive decision-making for healthcare professionals.

OBJECTIVE AND RATIONALE

This review provides a detailed and objective overview of research in this field. We consider the global prevalence of OTC analgesia during pregnancy, explain the current mechanistic understanding of how analgesic compounds cross the placenta and reach the foetus, and review current research on exposure associations with offspring health outcomes.

SEARCH METHODS

A comprehensive English language literature search was conducted using PubMed and Scopus databases. Different combinations of key search terms were used including 'over-the-counter/non-prescription analgesics', 'pregnancy', 'self-medication', 'paracetamol', 'acetaminophen', 'diclofenac', 'aspirin', 'ibuprofen', 'in utero exposure', 'placenta drug transport', 'placental transporters', 'placenta drug metabolism' and 'offspring outcomes'.

OUTCOMES

This article examines the evidence of foetal exposure to OTC analgesia, starting from different routes of exposure to evidence, or the lack thereof, linking maternal consumption to offspring ill health. There is a very high prevalence of maternal consumption of OTC analgesics globally, which is increasing sharply. The choice of analgesia selected by pregnant women differs across populations. Location was also observed to have an effect on prevalence of use, with more developed countries reporting the highest consumption rates. Some of the literature focuses on the association of in utero exposure at different pregnancy trimesters and the development of neurodevelopmental, cardiovascular, respiratory and reproductive defects. This is in contrast to other studies which report no associations.

WIDER IMPLICATIONS

The high prevalence and the challenges of reporting exact consumption rates make OTC analgesia during pregnancy a pressing reproductive health issue globally. Even though some healthcare policy-making authorities have declared the consumption of some OTC analgesics for most stages of pregnancy to be safe, such decisions are often based on partial review of literature. Our comprehensive review of current evidence highlights that important knowledge gaps still exist. Those areas require further research in order to provide pregnant mothers with clear guidance with regard to OTC analgesic use during pregnancy.

The association between analgesic drug use in pregnancy and neurodevelopmental disorders: protocol for an umbrella review

BACKGROUND

Maternal prenatal health has been shown to be an important influence on children's developmental outcomes, which has led to an increased emphasis on providing more information to support clinical decisions in pregnancy. Several systematic reviews suggest that analgesic drug use during pregnancy may have neurodisruptive properties. However, no firm conclusions have yet been drawn on the associations between prenatal analgesic drug use and children's long-term development of neurodevelopmental disorders such as autism spectrum disorder (ASD) or attention deficit hyperactivity disorder (ADHD). Therefore, an umbrella review is proposed for the purpose of examining the associations between maternal analgesic drug use during pregnancy and diagnoses of neurodevelopmental disorders.

METHODS

Included systematic reviews will consist of studies examining the effect of maternal prenatal analgesic drug use, specifically ibuprofen, acetaminophen, aspirin, naproxen, diclofenac, and ketoprofen, on children's neurodevelopmental disorder status. Examined drugs were restricted to those readily accessible and frequently used by pregnant women, and with characteristics that allow them to cross the placenta and directly affect fetal development. Outcomes will be restricted to formal clinical diagnoses of ASD and/or ADHD. Two reviewers will independently identify eligible reviews from six databases (e.g., PubMed, EMBASE, PsychINFO) from inception dates of databases to the date of data extraction, and conduct manual searches of reference lists, consultation with field experts, and scan of pre-print archives. Extracted data will also include short qualitative summaries by both reviewers. As part of quality assessment, a standardized measurement tool to assess systematic reviews (AMSTAR 2) will be used. A narrative synthesis is proposed to integrate findings from different, potentially methodologically heterogeneous, studies.

DISCUSSION

This umbrella review of associations between maternal prenatal use of analgesic drugs and children's neurodevelopmental disorders could allow for firmer conclusions to be drawn through the synthesis of all relevant published research. The synthesis of findings using high-quality evidence could provide more accurate healthcare information on the long-term effects of analgesic drugs on neurodevelopment, to better guide future clinical decisions during pregnancy. This review will also allow gaps and methodological differences in the literature to be identified, informing recommendations for future research.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42020179216 .

Molecular and Mechanical Mechanisms Regulating Ductus Arteriosus Closure in Preterm Infants

Failure of ductus arteriosus closure after preterm birth is associated with significant morbidities. Ductal closure requires and is regulated by a complex interplay of molecular and mechanical mechanisms with underlying genetic factors. In utero patency of the ductus is maintained by low oxygen tension, high levels of prostaglandins, nitric oxide and carbon monoxide. After birth, ductal closure occurs first by functional closure, followed by anatomical remodeling. High oxygen tension and decreased prostaglandin levels mediated by numerous factors including potassium channels, endothelin-1, isoprostanes lead to the contraction of the ductus. Bradykinin and corticosteroids also induce ductal constriction by attenuating the sensitivity of the ductus to PGE2. Smooth muscle cells of the ductus can sense oxygen through a mitochondrial network by the role of Rho-kinase pathway which ends up with increased intracellular calcium levels and contraction of myosin light chains. Anatomical closure of the ductus is also complex with various mechanisms such as migration and proliferation of smooth muscle cells, extracellular matrix production, endothelial cell proliferation which mediate cushion formation with the interaction of blood cells. Regulation of vessel walls is affected by retinoic acid, TGF-β1, notch signaling, hyaluronan, fibronectin, chondroitin sulfate, elastin, and vascular endothelial cell growth factor (VEGF). Formation of the platelet plug facilitates luminal remodeling by the obstruction of the constricted ductal lumen. Vasa vasorum are more pronounced in the term ductus but are less active in the preterm ductus. More than 100 genes are effective in the prostaglandin pathway or in vascular smooth muscle development and structure may affect the patency of ductus. Hemodynamic changes after birth including fluid load and flow characteristics as well as shear forces within the ductus also stimulate closure. Current pharmacological treatment for the closure of a patent ductus is based on the blockage of the prostaglandin pathway mainly through COX or POX inhibition, albeit with some limitations and side effects. Further research for new agents aiming ductal closure should focus on a clear understanding of vascular biology of the ductus.

Association between maternal acetaminophen use and adverse birth outcomes in a pregnancy and birth cohort

INTRODUCTION

Acetaminophen is the only analgesic recommended for use during pregnancy. This use has recently been linked to childhood developmental disorders, a finding that requires further investigation. Adverse birth outcomes-preterm birth, low birthweight, and small for gestational age-are associated with increased risk of developmental disorders and can serve as intermediate outcomes when examining the impact of maternal acetaminophen use.

METHODS

Clinical and lifestyle-factor data were gathered from 1200 women within the Ontario Birth Study who delivered between January 2013 and June 2017. Poisson regression with robust error variance was used to estimate the relationship between acetaminophen use before and during pregnancy and low birthweight, preterm birth, and small for gestational age.

RESULTS

Offspring of mothers who used acetaminophen before pregnancy had a higher risk of low birthweight and small for gestational age. Acetaminophen use <once/week was associated with small for gestational age, adjusted relative risk (aRR) = 1.46 (95% CI 1.02, 2.11). Acetaminophen use ≥once/week was associated with both small for gestational age, RR = 1.82 (95% CI 1.12, 2.94), and low birthweight, aRR = 2.16 (95% CI 1.02, 4.54). Acetaminophen use during pregnancy was not associated with the examined outcomes.

CONCLUSIONS

Prepregnancy acetaminophen use may be associated with higher risk of adverse birth outcomes.

Low neurodevelopmental performance and behavioural/emotional problems at 24 and 48 months in Brazilian children exposed to acetaminophen during foetal development

BACKGROUND

Several studies have reported that there is an association between developmental and emotional/behavioural problems in children exposed to acetaminophen during foetal development. However, few studies have focused on development and behavioural outcomes in early life.

OBJECTIVES

To test the association between prenatal exposure to acetaminophen and low neurodevelopmental performance at 24 months and behavioural/emotional problems at 48 months of life.

METHODS

We used data from the 2004 Pelotas Birth Cohort, a population-based longitudinal prospective study. Neurodevelopment was evaluated at 24 months using Battelle's Developmental Inventory (BDI) (n = 3737). We assessed global function as well as each domain (personal-social, adaptative, motor, cognitive, and communication). Behavioural/emotional problems were assessed at 48 months using the Child Behaviour Checklist (CBCL) (n = 3624). We used the CBCL total, externalising, and internalising symptomatology and individual subscales (withdrawn, somatic complaints, anxious/depressed, social problems, cognitive problems, attention problems, aggressive behaviour, and rule-breaking behaviour). Acetaminophen use during pregnancy was retrospectively assessed at the perinatal follow-up. Poisson regression and multiple linear regression analyses were used to test the association, adjusting for several family and maternal sociodemographic and health factors, medication use during pregnancy, and the sex of the child.

RESULTS

Acetaminophen exposure during prenatal development was not associated with low neurodevelopmental performance at 24 months assessed using the BDI or to emotional and behavioural problems assessed at 48 months using the CBCL in the adjusted models.

CONCLUSIONS

We cannot confirm the existence of an association between acetaminophen used during pregnancy and low neurodevelopmental performance at 24 months and emotional/behavioural problems at 48 months of life based on the present results.

Acetaminophen use during pregnancy and the risk of attention deficit hyperactivity disorder: A causal association or bias?

BACKGROUND

The association between acetaminophen use during pregnancy and the development of attention deficit hyperactivity disorder (ADHD) in the offspring may be due to bias.

OBJECTIVES

The primary objective was to assess the role of potential unmeasured confounding in the estimation of the association between acetaminophen use during pregnancy and the risk of ADHD, through bias analysis. The secondary objective was to assess the roles of selection bias and exposure misclassification.

DATA SOURCES

We searched MEDLINE, Embase, Scopus, and the Cochrane Library up to December 2018.

STUDY SELECTION AND DATA EXTRACTION

We included observational studies examining the association between acetaminophen use during pregnancy and the risk of ADHD.

SYNTHESIS

We meta-analysed data across studies, using random-effects model. We conducted a bias analysis to studies that did not adjust for important confounders, to explore systematic errors related to unmeasured confounding, selection bias, and exposure misclassification.

RESULTS

The search resulted in seven studies included in our meta-analysis. When adjusted estimates were pooled across all studies, the risk ratio (RR) for ADHD was 1.35 (95% confidence interval [CI] 1.25, 1.46; I²  = 48%). Sensitivity analysis for unmeasured confounding in this meta-analysis showed that a confounder of 1.69 on the RR scale would reduce to 10% the proportion of studies with a true effect size of RR >1.10. Unmeasured confounding bias analysis decreased the point estimate in five of the seven studies and increased in two studies, suggesting that the observed association could be confounded by parental ADHD. Unadjusted and bias-corrected risk ratios (bcRRs) were: RR = 1.34, bcRR = 1.13; RR = 1.51, bcRR = 1.17; RR = 1.63, bcRR = 1.38; RR = 1.44, bcRR = 1.17; RR = 1.16, bcRR = 1.18; RR = 1.25, bcRR = 1.05; and RR = 0.99, bcRR = 1.18.

CONCLUSIONS

Bias analysis suggests that the previously reported association between acetaminophen use during pregnancy and an increased risk of ADHD in the offspring may be due to unmeasured confounding. Our ability to conclude a causal association is limited.

Associations of acetaminophen use during pregnancy and the first year of life with neurodevelopment in early childhood

BACKGROUND

Over-the-counter analgesic use during pregnancy, particularly acetaminophen, may be associated with negative developmental outcomes in children.

OBJECTIVE

Estimate associations of prenatal and early-life exposure to acetaminophen in early childhood with cognitive, motor, and language skills in two birth cohorts.

METHODS

The American Project Viva cohort (1217 mother-child pairs enrolled 1999-2002) assessed cognition at approximately 3 years using the Peabody Picture Vocabulary Test and the Wide Range Achievement of Visual Motor Abilities (WRAVMA). The Brazilian 2015 Pelotas Birth Cohort (3818 mother-child pairs) assessed cognition at 2 years using the INTERGROWTH-21st Neurodevelopment Assessment. We used linear regression to estimate associations of acetaminophen use during pregnancy (Project Viva and Pelotas) and infancy (Project Viva) with children's cognitive scores adjusted for maternal age, pre-pregnancy body mass index, education, parity, race/ethnicity, smoking and alcohol use during pregnancy, depression during pregnancy, antibiotic and ibuprofen use during pregnancy, household income, and child's sex.

RESULTS

In Project Viva, exposure to acetaminophen in both the 1st and 2nd trimester of pregnancy was associated with lower WRAVMA drawing scores (β -1.51, 95% CI -2.92, -0.10). However, in Pelotas, exposure to acetaminophen in both the 1st and 2nd trimester of pregnancy was not associated with INTER-NDA motor scores (β 0.02; 95% CI -0.05, 0.09) and was associated with higher INTER-NDA total scores (β 0.08, 95% CI 0.01, 0.16). Other comparisons did not show evidence for any associations.

CONCLUSIONS

Inconsistencies and lack of specificity of the findings did not clarify the research question considering that we still have a large variability and uncertainty to define the risk or safety in the use of acetaminophen related to cognition in early childhood. More studies using better exposure assessment and better confounding variables are needed to clarify these associations.

Associations of prenatal or infant exposure to acetaminophen or ibuprofen with mid-childhood executive function and behaviour

BACKGROUND

Over-the-counter analgesics during pregnancy or infancy may be related to neurobehavioural problems in children, but little is known about effects of different analgesic types, dosage, and timing.

OBJECTIVES

Examine associations of acetaminophen and ibuprofen use during pregnancy and infancy with executive function and behaviour problems in children.

METHODS

We included 1225 mother-child pairs from Project Viva, a pre-birth cohort study. We assessed prenatal acetaminophen and ibuprofen use in early and mid-pregnancy and infant use in the first year of life using questionnaires. Parents and classroom teachers assessed child behaviours in mid-childhood (median 8 years), using the Behavior Rating Inventory of Executive Function (BRIEF) and the Strengths and Difficulties Questionnaire (SDQ), with higher scores indicating worse functioning for both. We examined associations of acetaminophen and ibuprofen use during pregnancy and infancy with mid-childhood neurobehavioural outcomes using linear regression models adjusted for potential confounders.

RESULTS

During pregnancy, 46.1% of mothers used acetaminophen ≥10 times and 18.4% used any ibuprofen. In the first year, 65.3% and 39.6% of infants received acetaminophen and ibuprofen ≥6 times, respectively. Higher (≥10 vs <10 times) prenatal acetaminophen (β 1.64 points; 95% confidence interval [CI] 0.59, 2.68) and any ibuprofen (β 1.56, 95% CI 0.19, 2.92) were associated with higher parent-rated BRIEF global scores. Patterns of association were linear across categories and were similar for other parent- and teacher-rated outcomes. Infancy exposure (≥6 vs <6 times) to acetaminophen (β 1.69, 95% CI 0.51, 2.87) and ibuprofen (β 1.40, 95% CI 0.25, 2.55) were associated with higher parent-rated BRIEF GEC scores but associations with teacher-rated scores were weaker.

CONCLUSIONS

Prenatal and early-life exposure to acetaminophen and ibuprofen were associated with poorer executive function and behaviour in childhood. These findings highlight the need for further research on the mechanisms through which analgesics may act on fetal and child brain development.

Acetaminophen use in pregnancy: Examining prevalence, timing, and indication of use in a prospective birth cohort

BACKGROUND

Previous studies of prenatal acetaminophen use have not addressed what indications and maternal co-factors describe acetaminophen use.

OBJECTIVE

The objective of this study was to describe these parameters in a well-characterised, prospective birth cohort.

METHODS

Data were drawn from the MotherToBaby study of pregnant women enrolled from 2004 to 2018. Daily acetaminophen diaries were calculated for all exposed women with complete dose and duration information. Descriptive statistics were used to assess maternal characteristics associated with acetaminophen use. Prevalence by 2-year interval was described, and linear regression was used to test for trend. Indication of use and dose per indication were summarised.

RESULTS

Of 2441 subjects, 1515 (62%) reported use of acetaminophen. Over the 15-year period, there was a decline in use of 2.5% for each 2-year period (test for trend = 0.001) with 58% reporting acetaminophen use in 2017-2018. Among women with acetaminophen use in pregnancy (n = 1515), 58% reported <10 days of use, 13% reported 10-19 days of use, 9% reported 20-44 days of use, and 9% reported 45 or more days of use. Twelve per cent had undefined duration of use. Increasing duration of exposure was associated with tobacco use, obesity, self-reported depression or anxiety, and antidepressant use. The most frequently reported indication was headache, however, indication varied by duration of use, with more women reporting use for sleep or pain/injury in the categories with the longest duration of use. Median dose per exposed day was highest among those reporting use for sleep, and higher doses were more frequently reported for arthritis, injury, and pain.

CONCLUSION

Acetaminophen is used by the majority of pregnant women, and some continue to use for many weeks in pregnancy. Given the heterogeneity in duration of use, indication, and dose, studies that estimate the risk of adverse outcomes associated with acetaminophen must carefully consider these factors.