People are said to be suffering from infertility when they've been trying to get pregnant for a year, but haven't been able to conceive. There are certain underlying reasons as to why someone cannot get pregnant and it is important to consult your health care provider for a treatment plan.
Sources:
https://www.mayoclinic.org/diseases-conditions/infertility/symptoms-causes/syc-20354317
https://www.medicalnewstoday.com/articles/165748
https://my.clevelandclinic.org/health/diseases/16083-infertility-causes
https://www.who.int/news-room/fact-sheets/detail/infertility