With the rapid development of assisted reproduction technology, IVF and its related derivatives (blastocyst culture technology, freezing technology, etc.) have become the most important therapeutic means to treat infertility. However, repeated failures after blastocyst transfer and low live birth rate of IVF babies have become the most difficult problems in clinical medicine. In recent years, many researches have been conducted on the principle, evaluation and in-depth discussion of IVF from different angles, which has led to a new breakthrough in IVF fertility techniques. Among them, the size of the progesterone value is the key to determine the success of the pregnancy cycle. Progesterone is very important for a woman’s conception period. Progesterone is a natural secretion secreted by the body and is an essential hormone for fertility. Whether you conceive naturally or opt for IVF techniques, every pregnancy relies on the assistance of progesterone, which is the single most important condition that contributes to the bonding of the embryo to the uterine wall; in addition, progesterone also aids in the formation of the placenta, which will provide the fetus with nutrients for up to nine months. If progesterone levels are insufficient during pregnancy, the risk of miscarriage is extremely high. Progesterone, also known as progesterone. It is a natural progesterone secreted by the corpus luteum of the ovary, which has a significant morphological effect on the estrogen-excited endometrium in vivo, and is necessary for the maintenance of pregnancy. Progesterone is clinically used for reactive diagnosis of causes of amenorrhea or amenorrhea such as preeclampsia, habitual abortion, and so on. Its role is mainly as follows: 1, in the late menstrual cycle to make the uterine mucosa gland growth, uterine congestion, endothelial thickening, for the implantation of the fertilized egg to prepare. After implantation of the fertilized egg, it will produce the placenta and reduce the excitability of the pregnant uterus, inhibit its activities, so that the fetus grows safely; 2, under the joint action of estrogen, it will promote the full development of the breasts to prepare for breast milk production; 3, it will make the mouth of the uterine cervix close, and the mucus will be reduced and thickened, so that it is not easy for sperms to penetrate; when the dose is large, it will inhibit the secretion of the pituitary glandular gonadotropin through the negative feedback of hypothalamus, which will produce the effect of inhibiting ovulation; 4, it will compete with the antagonistic effect on ovulation. 4. Competitively opposing aldosterone, prompting the excretion of sodium and chloride ions and diuresis. Some women have insufficient progesterone secretion due to luteal insufficiency or immature development of the fertilized egg itself. Without sufficient progesterone, the fertilized egg will not be able to successfully implant, and it is even more of a luxury for it to develop and grow in the mother’s body, and this leads to the occurrence of infertility. However, there is a luteal support step in the IVF fertility cycle, which serves to replenish the woman with progesterone. After IVF embryo transfer, the woman’s body does not produce enough progesterone in synchronization, which can prevent the blastocysts from settling and developing successfully, and may lead to preeclamptic miscarriage. Therefore, the IVF process basically involves a luteal support session, whose main function is to preserve the fetus. A certain amount of progesterone hormone level is necessary to maintain pregnancy, and high levels of progesterone play a significant calming effect on the enlarged uterus is important for early pregnancy support. Progesterone relaxes the uterine muscle fibers and reduces their excitability, while reducing the sensitivity of the pregnant uterus to contractions, decreasing uterine contractions and favoring the growth and development of the fertilized egg in the uterus. Conversely, miscarriage can occur. Progesterone can be categorized into natural progesterone and exogenous progesterone. Natural progesterone is produced from your own body, by the ovaries; whereas the medications or injections taken by pregnant women are exogenous progesterone. The role of exogenous progesterone in relation to fertility is obvious, as they allow women to achieve pregnancy. Does exogenous progesterone cause endocrine imbalance? Does it adversely affect the development of the baby? Exogenous progesterone will not cause an imbalance in the endocrine level of women, on the contrary, the right amount of exogenous progesterone can help women to achieve a relatively stable state of female hormone levels; in vitro fertilization of babies is the crystallization of high-tech medical science, so do not be blind and lead to excessive progesterone to the fetus caused by the harm. Clinical proof: the right amount of progesterone supplementation will not cause harm to the baby. The progesterone is to help the fetus to get the required amount of “natural hormones”, which are available to pregnant women during pregnancy, in line with the amount of physiological hormone levels that pregnant women should achieve under normal circumstances as a guideline, the normal level of physiological hormones is also to ensure that the success of in vitro fertilization is the key to success, so there is no need to worry.