Fertility can be influenced by factors affecting either partner, and sometimes both. In women, problems with ovulation, age-related changes in egg quantity and quality, blocked fallopian tubes, endometriosis and certain uterine conditions can affect conception. In men, low sperm count, reduced sperm movement or abnormal sperm shape, hormonal problems and certain testicular conditions may play a role. Lifestyle factors such as smoking, excess alcohol, recreational drug use and obesity can also affect fertility. In some couples, no clear cause is identified despite evaluation.

A fertility evaluation generally involves both partners rather than focusing only on the woman. It begins with a detailed medical, reproductive and sexual history and a physical examination. Depending on the situation, women may have ovulation or hormone testing, pelvic ultrasound or tests to assess the uterus and fallopian tubes. Men commonly undergo semen analysis to assess sperm count, movement and shape, with additional hormonal or other testing when indicated. The specific tests depend on age, medical history and the couple's circumstances.

Treatment depends on the underlying cause, how long the couple has been trying, age and individual preferences. Options may include lifestyle changes, medicines to support ovulation or address hormonal problems, surgery to correct certain reproductive conditions, or intrauterine insemination (IUI). Assisted reproductive techniques such as IVF may be considered when other approaches are unlikely to work or have not been successful. Treatment may also involve donor eggs or sperm in selected situations.

IVF may be considered when factors such as blocked or damaged fallopian tubes, certain ovulation problems, unexplained infertility or some forms of male-factor infertility make conception difficult. It may also be considered when other fertility treatments have not worked, or when there is a need to reduce the risk of passing on certain genetic conditions. IVF involves stimulating the ovaries, collecting eggs, fertilising them with sperm in a laboratory and transferring resulting embryos into the uterus. Whether IVF is appropriate depends on the couple's medical circumstances, age, fertility history and preferences.

Lifestyle does not explain every fertility problem, but it can influence reproductive health and treatment outcomes. Smoking can reduce fertility, while excess alcohol, recreational drugs and some medicines may also affect reproductive function. Maintaining a healthy weight and getting regular physical activity may support overall fertility. During fertility treatment, lifestyle factors can also influence the likelihood of success. Couples should discuss smoking, alcohol, supplements, medicines, diet, exercise and any other relevant habits with their fertility specialist rather than relying on unproven fertility remedies.

Useful questions include: What could be contributing to our difficulty conceiving? Do we both need testing? Which investigations are appropriate for us? What treatment would you recommend first, and why? What are the expected benefits, risks and costs? How long should we try one treatment before considering another? If IVF is recommended, what factors may affect our chances of success? Couples can also ask about the possibility of multiple pregnancy, side effects, alternatives and what happens if the first treatment does not work.