Answer
Diethylstilbestrol is contraindicated during pregnancy because it is a known human teratogen; high doses in the first trimester are associated with vaginal carcinoma, urogenital abnormalities and reduced fertility in female offspring, and an increased risk of hypospadias is reported in male offspring.
Sources for this answer
- Diethylstilbestrol 1mg film-coated tabletBrown & Burk UK Ltd · emc · SmPC §4.6 Fertility, pregnancy and lactation · Version 2Document updated
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