Fertility: Busulfan can lead to suppression of ovarian function and amenorrhoea in women and suppression of spermatogenesis in men. It may cause sterility in both sexes. In women, busulfan may cause severe and persistent ovarian failure, including failure to achieve puberty after administration to young girls and pre-adolescents at high-dose. It may also cause male infertility, azoospermia and testicular atrophy in male patients receiving busulfan. (See Pharmacology: Toxicology: Non-Clinical Information: Reproductive Toxicology under Actions).
Pregnancy: As with all cytotoxic chemotherapy, adequate contraceptive precautions should be advised when either partner is receiving busulfan.
The use of busulfan should be avoided whenever possible during pregnancy, particularly during the first trimester.
In every individual case, the expected benefit of treatment to the mother must be weighed against the possible risks to the foetus.
A few cases of congenital abnormalities, not necessarily attributable to busulfan, have been reported and third trimester exposure may be associated with impaired intra-uterine growth. However, there have also been many reported cases of apparently normal children born after exposure to busulfan in utero, even during the first trimester.
Studies of busulfan treatment in animals have shown reproductive toxicity (see Pharmacology: Toxicology: Non-Clinical Information under Actions). The potential risk for humans is largely unknown.
Lactation: It is not known whether busulfan or its metabolites are excreted in human breast milk. Mothers receiving busulfan should not breast-feed their infants.