Can infertility be genetic?

Yes, in several distinct ways. In men, genetic causes are well recognised. Karyotype abnormalities — most commonly Klinefelter syndrome — and Y-chromosome microdeletions are the two established causes, and testing is recommended where there is azoospermia or a very low count with other findings. The Y-chromosome result can change what treatment is possible. Complete deletion of certain regions means sperm have not been retrieved by surgical extraction, so surgery is not indicated — while other deletions carry a good chance of retrieval. That is why testing belongs before any surgical plan. Cystic fibrosis gene changes cause absence of the vas deferens, which presents as obstructive azoospermia in an otherwise healthy man. Where this is found, the female partner should be offered genetic testing too, because of implications for the child. In women, genetic causes include Turner syndrome and other X-chromosome abnormalities, and the fragile X premutation, which is associated with premature ovarian insufficiency. Fragile X testing is recommended where there is ovarian insufficiency or a relevant family history — and a positive result has implications for relatives, not just for you. The honest broader position, from the AUA/ASRM guideline: the genetic basis of male infertility has only been superficially explained, and most cases of apparently unexplained severe male infertility likely have a genetic basis not yet characterised. So a normal genetic test does not mean there is no genetic cause — only that current testing did not find one.