It is not only the wife’s medication that needs attention before pregnancy, but the husband’s medication needs special attention as well. Studies have shown that many drugs can affect the quality of sperm and eggs, or cause fetal malformations. The problem of “ignoring medication” must be alerted to couples preparing for pregnancy. Under normal circumstances, there is a protective layer between the testicular tissue and the blood flowing through the testicles, known medically as the blood-testis barrier. This barrier prevents certain substances in the blood from entering the testicles. However, many drugs can cross the blood-testis barrier and affect the healthy union of sperm and egg. For example, some common immunomodulators, like cyclophosphamide, nitrogen mustard and cisplatin, have strong toxic effects that can directly disrupt the synthesis of sperm DNA, including causing changes in the composition of genetic material, chromosomal abnormalities and sperm malformations. Like male infertility, women have habitual abortions (early embryo loss), part of which is the result of damaged male sperm. Ciclovir is also not well suited for preconception husbands. The main ingredient of ciclovir is cetirizine hydrochloride, which is an antihistamine and can have a negative effect on male sperm quality. In fact, not only antihistamines, but also anticancer drugs, caffeine, morphine, steroids, diuretics, etc., can have an impact on the quality of male sperm.