In normal pregnancy, the synthesis of PlGF gradually increases with the increase of gestational age, which is consistent with the change of placental oxygen supply during pregnancy. In the first trimester, the placenta is in a relatively hypoxic environment, the placental circulation has not been established, and the serum level of PlGF is low; as the pregnancy progresses, to 10-12 weeks of pregnancy, the intervillous blood flow is established, and the placenta develops to the second trimester, and the maternal blood flow increases and oxygen As the partial pressure increases, the synthesis of PlGF also gradually increases.

Research Shows,PlGF levels are low before 15 weeks of gestation, and PlGF expression increases rapidly at 15 to 26 weeks of gestation, and reaches a peak at 28 to 30 weeks of gestation，From late pregnancy to childbirth, as the placenta matures, ages, and functions decline, PlGF levels gradually decrease. Especially during childbirth, due to the increasing uterine contractions, the corresponding blood supply decreases, and gradual hypoxia, PlGF levels will be significantly reduced.

HDP is a disease unique to pregnancy and a serious disease that causes morbidity and mortality in pregnant women and perinatal infants.The characteristic of HDP is that the condition continues to worsen as the pregnancy progresses. Early diagnosis and intervention will help to improve the prognosis of mothers and children.Although the etiology and pathogenesis of HDP have not yet been elucidated, the theory of uterine-placental ischemia or "placental shallow implantation" is still accepted by most scholars.

In HDP, the erosive ability of trophoblast cells on the spiral artery of the uterus decreases, leading to shallow blastocyst implantation. The physiological changes of the spiral artery are limited to some blood vessels in the decidual layer. The injury site triggers the production of a series of anti-angiogenic factors, leading to a series of pathological changes in HDP such as platelet aggregation, thrombosis, and vasoconstriction. Placental ischemia plays a central role in the pathogenesis of HDP. This is because placental ischemia and hypoxia lead to a decrease in uterine perfusion pressure (RUPP), which stimulates the release of PlGF into the maternal circulation in animals or humans.

Cetin et al. found that the serum PlGF level of HDP pregnant women was significantly lower than that of normal pregnant women of the same gestational week (control group), and decreased as the disease worsened. At the same time, they also found that the PlGF level was significantly lower than that of the control group several weeks before the onset of clinical symptoms of HDP，It shows that the reduction of PlGF can predict the occurrence of HDP before the appearance of clinical symptoms, so as to better prevent HDP，improve the level of diagnosis and treatment and improve the prognosis of the perinatal period.

With the liberalization of the “comprehensive two-child” policy, the number of elderly and high-risk pregnant women will increase, and the subsequent incidence of high-risk pregnancy such as HDP and FGR will gradually increase. Find a convenient, fast, and highly specific screening method for pregnancy. Hierarchical management of lying-in women will help improve the perinatal outcome and improve the overall quality of the whole people.

PlGF plays an important role in trophoblast proliferation, placental neovascularization, etc，It is closely related to the occurrence and development of high-risk pregnancy such as HDP and FGR. On June 18 this year, the International Federation of Obstetrics and Gynecology (FIGO) released the latest "Practical Guidelines for Early Preeclampsia Screening and Prevention in Early Pregnancy", which pointed out that PLGF is the best detection index in early pregnancy screening. Therefore, the in-depth study of PlGF will help reveal the pathogenesis of these diseases and provide new means and methods for early prediction and dynamic monitoring of diseases.