USE OF INSECTICIDES IN PREGNANCY

SUMMARY: Insecticides are chemical compounds that are used in public health to kill vectors of disease such as mosquitoes, in agriculture to kill pests that damage crops, domestically to eradicate household and garden pests, and medically to eradicate body lice. Commonly used classes of insecticide include carbamates, organophosphates, pyrethrins/pyrethroids, and neonicotinoids.

There are a wealth of data describing pregnancy outcomes following gestational exposure to insecticides in general, but data relating to exposure to specific insecticides are generally scarce. Although associations with various adverse pregnancy outcomes and negative effects on infant/child neurodevelopment have been described following (usually chronic) insecticide exposure, findings of studies are generally inconsistent, and data are often confounded by multiple exposures and sociodemographic factors. Studies are further limited by potential misclassification of exposure as this is often assumed due to job title or place of residence. Few conclusions can therefore be drawn and there are no data specifically relating to acute exposure. Pregnant women should be advised to avoid exposure to insecticides. Where exposure cannot be avoided, personal protective equipment (PPE) should be employed as per the manufacturer’s instructions.

Low-level exposure to insecticides at any stage in pregnancy would not be regarded as medical grounds for termination of pregnancy. The need for additional fetal monitoring should be determined on a case-by-case basis, taking into account factors such as whether exposure was acute or chronic, whether personal protective equipment was employed, and the stage of pregnancy. Where high level exposure and/or symptoms of maternal toxicity have occurred, please contact UKTIS for a case-specific assessment of the risk of fetal harm. Maternal toxicity should be treated as for the non-pregnant patient and where a specific antidote is clinically indicated this should not be withheld on account of pregnancy. Other risk factors may also be present in individual cases which may independently increase the risk of adverse pregnancy outcome. Clinicians are reminded of the importance of consideration of such factors.