When should I consider referring a patient for specialist fertility assessment in cases of unexplained infertility?

Consider referring a patient for specialist fertility assessment in cases of unexplained infertility if:

• The woman is of reproductive age and has not conceived after 1 year of regular (every 2–3 days) unprotected sexual intercourse, with no known cause of infertility identified. Both partners should be assessed together at this point ².
• Earlier referral is warranted if the woman is aged 36 years or over, due to the age-related decline in fertility ².
• There is a known clinical cause of infertility or a history of predisposing factors for infertility, even if conception has not been delayed for a full year ².
• Couples identified as less likely to conceive (for example, due to previous pelvic inflammatory disease, previous abdominal or pelvic surgery, or abnormal semen analysis) should be offered earlier investigation and referral ¹,².

In summary, for unexplained infertility, referral is generally considered after 1 year of trying to conceive without success, but earlier if the woman is 36 or older or if risk factors for infertility exist.