Pregnancy teratogenic risks

Discuss general methods by which teratogenic risk and drug exposure during pregnancy and lactation can be minimized. 

Co-trimoxazole is a folate antagonist and should be avoided in the first and the third trimesters of pregnancy. In the third trimester there is an increased risk of neonatal haemolysis and methaemoglobinaemia, whereas in the first trimester there is a teratogenic risk caused by the trimethoprim (folate antagonist) component. 

Valproate, carbamazepine, and other anticonvulsants pose teratogenic risks. Despite this, treatment should continue during pregnancy, as the potential threat to the fetus by a seizure is greater However, it is mandatory to administer the lowest dose affording safe and effective prophylaxis. Concurrent high-dose administration of folate may... 

ACE inhibitors are contraindicated during the second and third trimesters of pregnancy because of the risk of fetal hypotension, anuria, and renal failure, sometimes associated with fetal malformations or death. Recent evidence also implicates first-trimester exposure to ACE inhibitors in increased teratogenic risk. Captopril, particularly when given in high doses to patients with renal insufficiency, may cause neutropenia or proteinuria. Minor toxic effects seen more typically include altered sense of taste, allergic skin rashes, and drug fever, which may occur in up to 10% of patients. 

In a large case-control surveillance study from Hungary in 38 151 pregnant women, oral erythromycin during pregnancy did not present a detectable teratogenic risk to the fetus (84). 

There are few data about the safety of topical retinoids during pregnancy. The risk of teratogenicity of topical tretinoin, if any, appears to be minimal (SEDA-18, 164) (109). However, there is a case report (110). 

Einarson A, Selby P, Koren G. Abrupt discontinuation of psychotropic drugs during pregnancy Eear of teratogenic risk and impact of counseling. J Psychiatry Neurosci 2001 26 44 8. 

Preliminary results of a prospective cohort study suggest that echinacea does not appear to pose a teratogenic risk. This study cohort was identified through Canada s Motherisk Program. Forty-five pregnancies in which echinacea was used have been followed thus far, with two spontaneous abortions, no stillbirths, and no malformations. Data on additional pregnancies will be collected (Gallo et al.,... 

A comment on the teratogenic risk associated with carbamazepine, with recommendations for its use in pregnancy, has been published [129. ... 

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