Use and validity of child neurodevelopment outcome measures in studies on prenatal exposure to psychotropic and analgesic medications - A systematic review

In recent years there has been increased attention to child neurodevelopment in studies on medication safety in pregnancy. Neurodevelopment is a multifactorial outcome that can be assessed by various assessors, using different measures. This has given rise to a debate on the validity of various measures of neurodevelopment. The aim of this review was twofold. Firstly we aimed to give an overview of studies on child neurodevelopment after prenatal exposure to central nervous system acting medications using psychotropics and analgesics as examples, giving special focus on the use and validity of outcome measures. Secondly, we aimed to give guidance on how to conduct and interpret medication safety studies with neurodevelopment outcomes. We conducted a systematic review in the MEDLINE, Embase, PsycINFO, Web of Science, Scopus, and Cochrane databases from inception to April 2019, including controlled studies on prenatal exposure to psychotropics or analgesics and child neurodevelopment, measured with standardised psychometric instruments or by diagnosis of neurodevelopmental disorder. The review management tool Covidence was used for data-extraction. Outcomes were grouped as motor skills, cognition, behaviour, emotionality, or "other". We identified 110 eligible papers (psychotropics, 82 papers, analgesics, 29 papers). A variety of neurodevelopmental outcome measures were used, including 27 different psychometric instruments administered by health care professionals, 15 different instruments completed by parents, and 13 different diagnostic categories. In 23 papers, no comments were made on the validity of the outcome measure. In conclusion, establishing neurodevelopmental safety includes assessing a wide variety of outcomes important for the child's daily functioning including motor skills, cognition, behaviour, and emotionality, with valid and reliable measures from infancy through to adolescence. Consensus is needed in the scientific community on how neurodevelopment should be assessed in medication safety in pregnancy studies. Review registration number: CRD42018086101 in the PROSPERO database.

A study of the risk of mental retardation among children of pregnant women who have attempted suicide by means of a drug overdose

BACKGROUND

The aim of the study was to estimate the effect on the fetal development of high doses of prescription drugs taken as a suicide attempt during pregnancy.

METHODS

Pregnant women were identified among self-poisoned females in the toxicological inpatient clinic in Budapest between 1960 and 1993. Congenital abnormalities, intrauterine development based on birth weight and post-conceptional age, mental retardation, cognitive-behavioral status were compared in exposed children born to mothers who had attempted suicide by means of a drug overdose during pregnancy with their siblings, born either before or after the affected pregnancy, as sib controls.

RESULTS

Of a total of 1 044 pregnant women, 74 used the combination of amobarbital, glutethimide and promethazine (Tardyl®, one of the most popular drugs for treatment of insomnia in Hungary) for suicide attempt. Of these 74 women, 27 delivered live-born babies. The mean dose of Tardyl® used for suicide attempts was 24 times the usually prescribed clinical dose. The rate of congenital abnormalities and intrauterine retardation was not higher in exposed children than in their sib controls. However, of the 27 exposed children, eight (29.6%) were mentally retarded (X²₁=79.7, p= Sig) while mental retardation did not occur among 46 sib controls. These exposed children were born to mothers who attempted suicide with Tardyl® between the 14th and 20th post-conceptional weeks. The components of Tardyl® used separately for a suicide attempt during pregnancy were not associated with a higher risk of mental retardation. Therefore the high doses of Tardyl® associated with the high risk for mental retardation may be due to the interaction of its three drug components.

CONCLUSIONS

The findings of the study showed that the high doses of a drug containing three components may be associated with a significantly increased risk for mental retardation without any structural defects, whereas each of these three component drugs taken alone was not associated with this adverse effect.

A study of the potential teratogenic effects of large doses of drugs rarely used for a suicide attempt during pregnancy

The available data set regarding pregnant women who attempted suicide during pregnancy was evaluated to estimate the teratogenic effect of very large doses of drugs based on the rate and distribution of congenital abnormalities of exposed children. These pregnant women were identified from patients of central toxicological inpatients clinic, Budapest, Hungary, 1960–1993. Of 1044 women with self-poisoning during pregnancy, 411 delivered live-born babies; 367 of these children were examined in this study. Data for 12 frequently used (10 or more times) drugs were published previously; this paper presents 77 medicines (58 drugs and 19 medicinal products including multiple components) that were rarely used for a suicide attempt by 197 pregnant women. Although 23 (11.7%) exposed children had congenital abnormalities (CAs), in general, a causal relationship of the CA and the drug taken by the pregnant woman cannot be assumed. This is because the suicide attempt often did not occur during a critical period for producing the CA. Of 67 pregnant women who attempted suicide between the 3rd and 12th postconceptional week, that is, the critical period of most major CAs, 7 (10.5%) children were affected with CAs. This high rate of CAs in exposed children can be explained by the intensive medical examinations, including diagnosis of mild CAs and minor anomalies, or the low socioeconomic status and hazardous lifestyle of mothers. None of the rarely used drugs was identified as a potential human teratogen. Experience of the authors shows the feasibility and benefits of using the self-poisoning model in estimating human teratogenic/fetotoxic risks of exposure to drugs.