Non-selective cyclooxygenase (COX) inhibitors, commonly referred to as nonsteroidal anti-inflammatory drugs (NSAIDs), are among the most taken pharmaceuticals. In adults, they can have a series of side effects, including especially gastroenterotoxicity, hepatotoxicity, nephrotoxicity, chondrotoxicity, and neurotoxicity, and they can induce allergic reactions. Any exacerbation of symptoms depends on the chemical structure of the drug, its dosage and duration of exposure, individual sensitivity, comorbidities and the degree of inhibition of basic COX isoenzymes - the constitutive (COX-2) and induced (COX-1) expressions. However, data on prenatal toxicity are inconsistent. Classic nonselective COX inhibitors do not result in an increase in the risk of developing significant congenital defects; however, if used in the late-pregnancy period, they can have an adverse effect on the foetus, by inducing the premature closure of the ductus arteriosus and by producing a tocolytic effect. Individual reports also indicate the increased risk of developing heart and anterior abdominal wall defects, as well as hypospadias.