Background: Placental insufficiency is a common and serious complication of the placenta during pregnancy, which affects about 10 to 15% of pregnancy. Placental insufficiency is one of the common clinical problems in obstetrics for mothers and fetuses because it is still a potential cause of preterm birth, preeclampsia, fetal growth restriction, and stillbirth. In the case of placental insufficiency, the placenta cannot provide enough oxygen and nutrition from the mother's blood to the fetus, which leads to fetal growth restriction, intrauterine fetal distress, low birth weight, stillbirth, neonatal asphyxia, or some birth defects later. Doppler ultrasound is a common method to evaluate the degree of placental blood circulation damage. However, until now, there is no consensus on the standard definition, specific diagnostic criteria, and common treatment guidelines for placental insufficiency. Aim: to analyze the effects of drugs (low-molecular weight heparin in single therapy LMWH and fluids replacement therapy in single therapy FRT or in combination therapy LMWH+FRT on ultrasonic Doppler blood flow indices and pregnancy outcomes of placental insufficiency in the third trimester of single pregnancies. Materials and Methods: 120 single pregnant Chinese women were included in this study from September 2019 to December 2020. 60 pregnant women with a high S/D ratio of the fetal umbilical artery in late single pregnancy were studied retrospectively as the case group, and 60 normal pregnant women with a normal S/D ratio of the fetal umbilical artery were taken as the control group in the same period. Among the cases, 22 cases were treated with low-molecularweight heparin (LMWH), 16 were treated with maternal fluids replacement therapy (FRT), and the others 22 were treated with LMWH + FRT. After 10 days of medication, the Doppler ultrasound blood flow indices (S/D ratio of the fetal umbilical artery and PS, PI, RI of the middle cerebral artery) were observed, and the indices before and after treatment were compared to observe the effectiveness of these drugs. Meanwhile, the pregnancy outcomes of the case group (n=60) and the control group (n=60) were recorded and compared.
Results:The study found that the mean S/D ratio of fetal umbilical artery in case group and control group was respectively 3.46±0.45 and 2.18 ±0.34, P-value= 0.000, had statistical significance before treatment; and was respectively 2.57 ±0.76 and 2.29 ±0.34, P-value = 0.000 was statistically significant too after treatment, which indicates that the S/D ratio of the fetal umbilical artery has significant significance in the evaluation of placental insufficiency. Further analysis showed that the women treated with LMWH, the mean value of S/D ratio of fetal umbilical artery before and after LMWH treatment was respectively 3.26± 0.84 and 2.25 ±0.25; the mean value of S/D ratio in the fetal umbilical artery before and after treatment was significantly different, which indicates that LMWH alone had a certain effect on improving fetal umbilical blood flow....