I. About chromosomes Generally, chromosomes need to be checked in two cases: the concentration of the male partner’s multiple routine semen examinations are less than 10 million/mL; those with a history of two (including two) or more spontaneous abortions, especially early abortions (within 3 months of pregnancy). During pregnancy, about 7% of spontaneous abortions occur, which can be considered as eugenics; however, among repeated abortions (two (including two) or more history of spontaneous abortions, especially early abortions (within 3 months of pregnancy)), further examination is needed to clarify the cause of abortion: about 50% of them are abnormal fetal chromosomes, the rest may be related to the woman’s intrauterine environment, and some are limited to the existing medical The rest may be related to the intrauterine environment of the woman, and some are of unknown origin due to the current medical level. The incidence of karyotype abnormality is 10-15% in azoospermia patients, 4-5% in oligospermia patients, and 1% in patients with normal or basically normal semen parameters. The Y chromosome microdeletion is mainly from genetic variation, and Y chromosome microdeletion occurs in 7% of male infertility patients, among which 3-7% of oligospermia patients have Y chromosome microdeletion. The Y chromosome microdeletion occurs in 7% of male infertility patients, including 3-7% of oligospermia patients and 13% of azoospermia patients. 96% of patients with complete deletion of AZFa region or simultaneous deletion of AZFb+c have azoospermia and 4% have severe oligospermia. Severe oligospermia caused by Y chromosome microdeletion: male offspring of patients with Y chromosome microdeletion also have Y chromosome microdeletion and may also face fertility problems. There are two treatment options to choose from: one can choose third generation IVF to select female offspring, but at a cost of about 50,000 yuan with a success rate of about 5% to 10%; or no offspring sex selection, but there is a risk of male offspring being infertile (Y chromosome microdeletion inherited to the male offspring, the risk of severe oligospermia, or even azoospermia). This should be discussed with your primary care physician.