Establishment Of Reference Intervals For Some Relevant Coagulation Indexes In Pregnant Women During Pregnancy

Objective This article aims to establish a preliminary reference interval for various coagulation indexes of pregnant women in our hospital through the research and analysis of various indicators such as routine coagulation indexes,platelet aggregation function and thromboelastography（TEG）of pregnant women in our hospital.Methods This study collected 450 normal pregnant women undergoing regular obstetrics in Ordos Central Hospital from November 2019 to November 2020,including early group（<14 gestational weeks）,mid-term group(14-27⁺⁶gestational weeks),and late group（≥28 gestational weeks）150 cases each.Prothrombin time（PT）,activated partial prothrombin time（APTT）,D-dimer（DD）,fibrin（proto）degradation products（FDP）,fibrinogen（FIB）,thrombin time（TT）,antithrombin III（AT-III）,platelet aggregation function（PAGT）,TEG value,PLT count value were detected and statistically analyzed.The plasma concentrations of various indicators in different pregnancy periods were all non-positive The percentile method is used to describe the reference interval,the concentration of D-dimer and FDP is expressed by the one-sided percentile method(P₉₅),and the other indicators are expressed by the two-sided percentile method(P_2.5～P_97.5)said,analyze the changes of various coagulation indexes in different pregnancy periods,initially establish the reference interval of various coagulation indexes for women in different pregnancy periods in our laboratory,and verify the feasibility of the reference interval.Results The results of the study showed that with the increase of gestational age,pregnant women’s PT,TT and ATⅢ,R value and K value levels showed a downward trend（P<0.05）,and the levels of DD,FDP,FIB,αangle,MA value and CI value showed a stepwise trend.The formula gradually increased（P<0.05）,and the APTT value and platelet aggregation function of women in the third trimester were not statistically significant compared with those in the second trimester（P>0.05）.The reference intervals of various coagulation indexes in different pregnancy periods are:first trimester:PT 10.44～12.78s,APTT 23.02～30.93s,D-Dr<0.93mg/L,FDP<2.32mg/L,FIB 1.80～4.39g/L,TT 14.38～18.30s,ATⅢ78.74～117.38%,PAGT 2.09～9.05,R value 4.02～8.53min,K value 1.16～2.53min,MA value 55.71～68.78mm,αangle 56.67～73.04°,CI value-2.32～2.66;second trimester:PT 10.54～12.43s,APTT 22.88～30.10s,D-D<1.44mg/L,FDP<4.34mg/L,FIB2.27～5.10g/L,TT 14.00～17.92s,ATⅢ78.61～109.92%,PAGT 2.59～10.63,R value3.62～7.69min,K value 1.03～2.36min,MA value 56.28～69.91mm,αangle 58.42～74.09°,CI value-2.01～2.93;Third trimester:PT 10.32～12.39s,APTT 22.38～30.32s,D-Dr<4.03mg/L,FDP<9.99mg/L,FIB 2.71～5.24g/L,TT 12.65～18.61s,ATⅢ71.98～110.85%,PAGT 2.34～11.65,R value 3.26～6.99min,K value 0.91～2.06min,MA value57.18～70.97mm,αangle 62.31～75.83°,CI value-0.73～3.47.Conclusion（1）The reference interval of PT,APTT,TT,K value,MA value and CI value in this study did not change significantly,and they were all within the reference interval of the normal non-pregnant population currently used in the laboratory;（2）Although the lower limit of the reference interval of AT-Ⅲand PAGT is lower than the current reference interval,the changes in the three trimesters are small;（3）The reference interval of D-D,FDP,FIB,R value andαangle significantly exceeds The current reference interval has been exceeded,and the fluctuation is large,which is most obvious in the second and third trimesters,and all have passed the verification to meet the requirements.（4）Therefore,the reference intervals of D-Dr,FDP,FIB,R value andαvalue established by healthy women in different pregnancy periods can be used in our laboratory to judge the abnormal hemostasis and coagulation function during pregnancy.Provide a strong basis.