要了解节育原理,必先了解生殖器官的构造、功能及怀孕的原理,以及受孕必须具备的条件。一、生殖器官的构造及功能女性外生殖器包括阴阜、大小阴唇、阴蒂、前庭及会阴。女性内生殖器包括阴道、子宫、卵巢和输卵管(图1)。 To understand the principle of birth control, we must first understand the structure of reproductive organs, function and principles of pregnancy, and pregnancy must have the conditions. First, the structure and function of genital organs Female genitalia, including the mons pubis, size labia, clitoris, vestibule and perineum. Female genitalia, including the vagina, uterus, ovaries and fallopian tubes (Figure 1).