Study On The Regularity Of Blood Pressure Changes In Pregnant Women And Its Influencing Factors

Background: Blood Pressure is one of the important indexes to evaluate the operation of human body.The abnormal blood pressure is related to the occurrence and prognosis of various diseases.As for pregnant women,blood pressure variability during pregnancy may have some impact on the pregnancy outcome of the fetus and mother.The prevalence of gestational hypertension in China is 9.4%.It happens with certain precursor factors,such as the fluctuation of normal range of blood pressure during pregnancy,normal high blood pressure,pre-hypertension and so on.This is because the occurrence of hypertension is caused by the gradual increase of blood pressure.It is possible to predict gestational hypertension and adverse pregnancy outcome theoretically by monitoring the variability of blood pressure in the normal range.Therefore,it is of great clinical and public health significance to study the changes of maternal blood pressure before and after pregnancy,during pregnancy to be antenatal.Objective: To obtain the characteristics and demographic data of blood pressure changes from pre-pregnancy to different stages of pregnancy by questionnaire.To explore the influencing factors of blood pressure changes in different periods of normal pregnancy.Methods: A total of 862 pregnant women who underwent antenatal examination and delivered successfully in our hospital from December 2016 to November 2017 were selected as the primary subjects.In turn,138 cases lacking the pre-pregnancy physical examination,74 cases using assisted reproductive technology to pregnancy,105 cases of missing mid-term antenatal examination data,68 cases of multiple pregnant women and 32 cases of hypertension before pregnancy were excluded.Finally,445 cases were selected.The pre-pregnancy data of pregnant women were investigated by questionnaire: the contents of the questionnaire included maternal name,age,height,weight before pregnancy,waist circumference before pregnancy,systolic blood pressure(SBP),SBP before pregnancy,diastolic blood pressure(DBP)and DBP before pregnancy,pregnancy history,delivery,occupation,annual income,educational level,folic acid supplementation,smoking history,drinking history,family history of hypertension,and blood routine indexes before pregnancy,etc.Collect physical examination data before pregnancy.Count the number of patients with high blood pressure during pregnancy.The number of patients with abnormal blood pressure variability was counted.The influencing factors of abnormal variability of blood pressure were analyzed.To analyze the predictive value of influencing factors on high systolic blood pressure,high diastolic blood pressure and abnormal blood pressure variability during pregnancy.Results:1.There were significant differences in systolic and diastolic blood pressure before pregnancy and during pregnancy(P<0.05).The SBP in mid-pregnancy was higher than that in early pregnancy and pre-pregnancy(P<0.05),and the SBP in late pregnancy was higher than that all before(P <0.05).DBP in the second trimester was higher than that in the first trimester and lower than that in the first trimester(P < 0.05),and DBP in the third trimester was higher than that in the second trimester,but still lower than that in the first trimester(P < 0.05).2.A total of 121 pregnant women had high blood pressure before or during pregnancy,occurring in pre-pregnancy(74 patients)and during pregnancy(96 patients)(P<0.05).Among them,78 were high SBP and 53 were high DBP.The high-value blood pressure of 75 pregnant women lasted only one stage,the high-value blood pressure of 14 pregnant women lasted two stages and 26 lasted three stages.3.A total of 59 pregnant women had 72 abnormal blood pressure fluctuations in stage 72,including 49 pregnant women with abnormal blood pressure fluctuation in pregnancy,of which 49 had abnormal blood pressure in single stage,8 had abnormal blood pressure fluctuation in stage 2.pregnant woman with abnormal blood pressure fluctuation in stage 3 and 1 pregnant woman with abnormal blood pressure fluctuation in stage 4.Abnormal blood pressure fluctuations were caused 31 times by SBP fluctuations and 41 times by DBP.In the abnormal fluctuation of blood pressure,there were 25 fluctuations in mid-pregnancy and 47 fluctuations in late pregnancy.4.Pre-pregnancy SBP,pre-pregnancy BMI and cortisol levels were high risk factors for high-value SBP in pregnant women(P <0.05).5.Pre-pregnancy DBP and occupation type were the high risk factors for high DBP during pregnancy in pregnant women(P <0.05).(6)Pre-pregnancy SBP,annual household income and total cholesterol levels are high risk factors for abnormal blood pressure fluctuations in pregnant women(P <0.05).(7)There was no significant difference between high-value SBP,DBP,abnormal fluctuation of blood pressure during pregnancy and normal SBP,DBP and no abnormal fluctuation of blood pressure during pregnancy(P <0.05).Conclusions:1.Compared with pre-pregnancy,the systolic and diastolic blood pressure of pregnant women in early pregnancy decreased significantly.The systolic blood pressure in the third trimester is higher than that in the pre-pregnancy level,and the diastolic blood pressure in the late pregnancy is still lower than that before pregnancy.2.The incidence of high-value blood pressure in the third trimester of pregnancy was significantly higher than that in the first and second trimester of pregnancy,and the high value blood pressure is not persistent.Over time,most of the high blood pressure can return to the normal range.3.Pre-pregnancy systolic high-normal blood pressure,pre-pregnancy BMI >24 kg/m2 and abnormally high cortisol levels are the risk factors for high-value systolic blood pressure during pregnancy,and pre-pregnancy diastolic blood pressure and occupational type are the risk factors for high-value diastolic blood pressure during pregnancy.As one of the abnormal manifestations of normal blood pressure,abnormal blood pressure fluctuation is affected by the factors including systolic blood pressure before pregnancy,family annual income and total cholesterol level.4.High systolic and diastolic blood pressure during pregnancy,and abnormal fluctuation of blood pressure during pregnancy had no effect on the outcome of pregnant women and newborns.