The goal of this clinical trial is to learn about in health conditions. The main questions it aims to answer are:

• The pathological significance of GPER in uterine artery dilation in preeclampsia
• The Mechanism of GPER Hippo Pathway Regulating CBS/H2S in Human Uterine Artery Smooth Muscle Cells (hUASMC) This project intends to use GPER interfering RNA, YAP1 interfering RNA, in vivo perfusion experiments of human uterine artery tissue, and single cell patch clamp technology to study hypotheses under physiological/pathological pregnancy conditions at the tissue, cellular, and molecular levels, revealing a novel signal transduction pathway of estrogen stimulating vasodilation, providing new ideas for studying the mechanism of uterine artery blood flow regulation. This research result will provide new targets for intervention and treatment of diseases such as fetal intrauterine growth retardation and preeclampsia.

1. Measure the content of H2S in uterine arterial smooth muscle and circulation of normal pregnancy and PE pregnant women, and analyze the relationship between the content of H2S in uterine arterial smooth muscle and circulation of PE pregnant women and PE.
2. Knock down the GPER and overexpression of GPER in HTR-8 cells, and detect the expression of GPER, CBS, and Hippo pathway related proteins using Western blot and qRT-PCR to verify the efficiency of knockdown and overexpression. Use different concentrations of H2S donor (GYY4137) to interfere with HTR-8 cells after treatment, and use RT-PCR and Western blot to detect the mRNA and protein expression of downstream molecules YAP and TAZ in Hippo pathway in cells, respectively.

Inclusion Criteria:

1. Full term pregnancy with clinical diagnosis of preeclampsia and normal pregnancy pregnant woman
2. Pregnant women undergoing lower segment cesarean section for delivery

Exclusion Criteria:

1. Combined with chronic hypertension, kidney disease, intrahepatic cholestasis, etc Other basic diseases;
2. Multiple pregnancy
3. Pregnant women undergoing vaginal delivery
4. Normal pregnant women who are<37 weeks or>40 weeks pregnant