How do people get sterile?

People can become sterile through various means, including medical procedures such as vasectomy for men and tubal ligation for women, which are intended to prevent pregnancy. Additionally, certain medical conditions, genetic factors, infections, or treatments like chemotherapy can lead to infertility. Lifestyle factors, such as excessive alcohol consumption or smoking, can also contribute to reduced fertility. In some cases, sterility may be a result of natural biological processes or aging.