Fertility, Pregnancy and Contraception — on Gefitinib

The prescribing information specifies effective contraception but does not mandate a single method. Hormonal methods — the pill, implant or injection — and intrauterine devices are generally considered effective. Barrier methods alone are typically regarded as less reliable. The right choice depends on your medical history and any other medicines you are taking, since some conditions that coincide with cancer treatment can affect which options are appropriate for you. Ask your oncologist or a gynaecologist to advise on what suits your specific situation.

Animal studies suggest gefitinib can affect fertility in both women and men, though whether this translates to lasting infertility in all humans is not yet fully established. What is clear is that the risk exists. Fertility preservation before treatment — egg, embryo or sperm freezing — is the only reliable way to protect future options with certainty. Ask your oncologist to refer you to a fertility specialist before your first dose if having children is something you want. This conversation is easier to have before treatment starts than after.

No. You should not breastfeed during treatment or for two weeks after your last dose. There is currently no data on whether gefitinib passes into human breast milk, and because of the potential for serious effects on a breastfed baby, the guidance is to avoid breastfeeding entirely during this period. If you have recently given birth and want to discuss feeding options, tell your oncologist — they can refer you to appropriate support while you are on treatment.

Yes. The prescribing information for gefitinib requires men whose partners could become pregnant to use effective contraception during treatment and for two weeks after the last dose. The drug may be present in semen, and its potential effects on a developing baby are not limited to exposure through the mother. Gefitinib may also affect sperm quality. If you want children in the future, ask about sperm banking before treatment starts — that option is not affected by what happens after treatment begins.

A washout period is the time needed for a drug to clear from your body after you stop taking it. For gefitinib, the prescribing information sets a minimum of two weeks after your last dose before you try to conceive. This is based on the drug's half-life — the time it takes for half the amount in your bloodstream to be eliminated. Your oncologist may advise waiting longer if there are other clinical reasons to do so. Do not attempt to conceive before the washout period is complete, even if you feel well and have no side effects.

This is a difficult situation and there is no single standard answer. Your oncologist will need to weigh the risk to the pregnancy against the urgency of treating your cancer. That balance depends on how far along you are, how aggressive the cancer is, and whether alternative treatments with a lower fetal risk profile exist. Some women in this situation delay treatment, some receive alternative drugs, and some continue after detailed counselling. This decision should involve a multidisciplinary team. Ask for that discussion as early as possible — ideally the same day you receive the diagnosis.