Egg retrieval is an important part of the IVF technique. Only one dominant follicle develops during a woman’s natural ovulation cycle and ovulation promotion is necessary to obtain multiple healthy eggs. The dosage and duration of IVF ovulation inoculations need to be tailored to the patient and will vary from person to person. Generally speaking, the duration of ovulation promotion injections is 10-14 days. The eggs grow under the effect of ovulation promotion drugs, but mature eggs cannot be obtained yet. In order to evaluate the development of the eggs in the follicles, the doctor must monitor the size of the follicles with an ultrasound machine and evaluate them with checking the estrogen level in the blood, and then adjust the dosage of the medication according to the follicles. For most patients, the medication needs to be continued for about 10 days, but the exact number of days also depends on the growth of the follicles, which may be as short as 8 days in some cases and up to 15-16 days in the longer ones. When estrogen levels match the number of follicles, the doctor can inject HGH to encourage the follicles to mature and remove the eggs before ovulation (approximately 35-36 hours after the HGH injection) using a painless egg retrieval technique. Throughout the ovulation promotion process, the doctor will identify the low and over-reactive cycles according to the patient’s specific situation, assess the quality of the eggs, understand the right time to obtain mature eggs, and ultimately decide on the timing of egg retrieval in order to obtain a larger number of mature eggs, while the patient’s full cooperation with the treatment is also crucial.