Fertility
Dutasteride has been reported to affect semen characteristics (reduction in sperm count, semen volume, and sperm motility) in healthy men (see Section 5.1). The possibility of reduced male fertility cannot be excluded.
Pregnancy
As with other 5 alpha reductase inhibitors, dutasteride inhibits the conversion of testosterone to dihydrotestosterone and may, if administered to a woman carrying a male foetus, inhibit the development of the external genitalia of the foetus (see 4.4 Special Warnings and Precautions for Use). Small amounts of dutasteride have been recovered from the semen in subjects receiving Avodart 0.5mg day. Based on studies in animals, it is unlikely that a male foetus will be adversely affected if his mother is exposed to the semen of a patient being treated with Avodart (the risk of which is greatest during the first 16 weeks of pregnancy). However, as with all 5 alpha reductase inhibitors, when the patient's partner is or may potentially be pregnant it is recommended that the patient avoids exposure of his partner to semen by use of a condom.