1. What is infertility? Infertility usually refers to 12 months of regular and normal sexual intercourse without contraception and no pregnancy. However, some patients may have a clear etiology that prevents them from conceiving normally, and for them, the 12-month wait is meaningless. These common etiologies include: severe menstrual disorders, long term severe endometriosis, history of tubal pregnancy and anatomical abnormalities, etc. All of these etiologies can lead to a significant decrease in female fertility. Because female fertility declines significantly with age, couples older than 35 years who have not been pregnant for 6 months without contraception should actively seek evaluation for infertility. 2. What are the main causes of infertility? There are many causes of infertility, which can be divided into female and male factors. Female factors account for 30%, male factors account for 30%, both factors account for 30%, and 10% of the factors have not yet been identified medically. Female factors include: (1) congenital abnormal development of reproductive organs (abnormal development of vulva, vagina, uterus, fallopian tubes, ovaries, hermaphroditism, etc.); (2) reproductive organ lesions, such as adhesions of fallopian tubes, uterus and pelvis or endometriosis; (3) endocrine dysfunction (ovulation disorder, luteal insufficiency, etc.); (4) immune function abnormalities; (5) other factors (malnutrition, thyroid dysfunction, chronic lactation, etc.) (5) other factors (malnutrition, thyroid dysfunction, chronic wasting diseases, various drugs, etc.); (6) increase in fertility age: women’s peak fertility is in their twenties, and fertility decreases significantly after 35. Male factors include: (1) sperm production and maturation disorders; (2) sperm transport channel lesions; (3) sexual life disorders; (4) accessory genital gland abnormalities; (5) immune factors; (6) other factors. 3.What tests are needed for infertility patients? The basic tests for infertility include the following: transvaginal ultrasound, serum sex hormone measurement and evaluation of the fallopian tubes and uterus (imaging or laparoscopy) are usually required for women; routine tests for men include basic semen analysis to assess semen volume, sperm concentration (sperm count), percentage of motile sperm (sperm motility), percentage of normal morphology (sperm morphology), sperm acrosome reaction and hypotonic swelling test. The physician may use transvaginal ultrasound to learn about the patient’s uterus and ovaries. Ultrasound can detect abnormal uterine pathologies such as congenital uterine malformations, uterine fibroids or endometrial polyps. It can also determine ovarian size, follicle count (sinus follicle count), and determine ovulation, which can reflect the patient’s responsiveness to ovulation-promoting drugs. In addition, abnormal ovarian tumors or cysts may be detected. In addition to routine vaginal ultrasound, infertile women may have a hysterosalpingogram (HSG), which is usually performed by a gynecologist and radiologist under X-ray fluoroscopy, to find out the patency of the fallopian tubes. Similar tests to hysterosalpingography are laparoscopy and hysteroscopy. The doctor will arrange the tests according to the situation of the infertile couple to find the cause of infertility and find the best way to help them conceive as soon as possible.