The main reason why it is not easy to get pregnant over 40 years old is that as women age, the function of the ovaries, especially the reserve function of the ovaries, will gradually decline, and the said decline in the reserve function means that the function of ovulation will decline, and clinically it is not easy to get pregnant over 40 years old. Therefore, if you are planning to get pregnant, it is best to get pregnant before the age of 35. If you are over 35 years old, you are of advanced maternal age and you will have more comorbidities clinically, so it is recommended to get pregnant again before 35 years old. If you are over 40, you will still be clinically pregnant, but your chances of getting pregnant have decreased. If you are planning to become pregnant, it is recommended that you have a full physical health assessment before preparing for pregnancy.