USE OF ETHYLENE GLYCOL IN PREGNANCY
Date of issue: May 2021, Version: 3
Ethylene glycol is an odourless, colourless, sweet-tasting liquid used as a coolant in brake fluid and antifreeze, and a precursor in polymer manufacture.
As with all chemicals, unnecessary exposure to ethylene glycol should be avoided during pregnancy. However, where occupational exposure is unavoidable, precautions should be taken to ensure that exposure is well within the recommended exposure limits and not associated with toxic symptoms.
The available data relating to occupational and acute ethylene glycol exposure in pregnancy are highly limited, consisting of a small number of exposed pregnancies detailed in descriptive studies.
Maternal toxicity associated with ethylene glycol exposure is likely to be a major determinant of risk to the fetus. However, due to the limited available data regarding the teratogenicity of ethylene glycol, it is not currently possible to state that an absence of maternal toxicity excludes the possibility of adverse events occurring in the developing fetus.
As ethylene glycol is highly toxic, where cases of poisoning occur in pregnancy, treatment should be as for the non-pregnant patient and should not be withheld on account of pregnancy. There are very limited data available concerning the use of the antidotes fomepizole and ethanol in pregnancy. However, when indicated, the maternal and fetal benefits of antidote treatment will outweigh the risks associated with untreated ethylene glycol poisoning. If treatment with an antidote is required, then fomepizole is preferred at all stages of pregnancy as ethanol can cause harmful fetal effects. However, where fomepizole is either unavailable or not considered appropriate, ethanol should not be withheld on account of pregnancy.
Exposure to ethylene glycol alone would not usually be regarded as medical grounds for termination of pregnancy. However, other risk factors may 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 when performing case-specific risk assessments. In all cases of ethylene glycol exposure in pregnancy, extended maternal and fetal monitoring may be warranted. Discussion with UKTIS is recommended in all cases.
This is a summary of the full UKTIS monograph for health care professionals and should not be used in isolation. The full UKTIS monograph and access to any hyperlinked related documents is available to NHS health care professionals who are logged in.
If you have a patient with exposure to a drug or chemical and require assistance in making a patient-specific risk assessment, please telephone UKTIS on 0344 892 0909 to discuss the case with a teratology specialist.
If you would like to report a pregnancy to UKTIS please click here to download our pregnancy reporting form. Please encourage all women to complete an online reporting form.