Effect Of Low Molecular Weight Heparin On Autoimmune Subclinical Hypothyroidism Recurrent Abortion

Background and Objective:Recurrent abortion is a complex disease affected by many factors,and its recurrence rate increases with the increase of the number of abortions and the age of pregnancy,which seriously affects the body and mental health of patients.It is one of the research hotspots in the field of obstetrics and gynecology.Current studies on the pathogenesis of recurrent abortion have found that the main causes of recurrent abortion include: anatomical abnormalities of reproductive system,endocrine function abnormalities,immune function abnormalities,coagulation system abnormalities,genetic system abnormalities,and some recurrent abortion causes unknown.Treatment varies greatly depending on the cause.Recurrent abortion caused by endocrine system abnormalities is relatively common clinically.The levels of thyroid stimulating hormone(TSH)receptor thyroperoxidase antibody and anti-thyroglobulin antibody in subclinical hypothyroidism patients are increased,which can competitively bind to luteinizing hormone(LH)receptors in granular lutein cells,thus reducing progesterone synthesis.Further lead to pregnancy luteal insufficiency induced abortion.It also stimulates the increase in the number and activity of peripheral blood NK cells,thus resulting in disorder of immune system and pregnancy loss.Elevated thyroid autoantibodies will lead to deposition of antigen and antibody immune complex in placenta,causing immune response damage to local blood vessels and formation of microthrombus,leading to pregnancy loss.Meanwhile,positive thyroid autoantibodies will also lead to increased risk of abortion.Individual levothyroxine therapy was performed by measuring thyroid function during pregnancy.Low molecular heparin(lowmolecularweightheparin,LMWH)as a common anticoagulant and antithrombotic drugs in clinical use is very broad.It can improve the hypercoagulable state of the blood and improve the blood circulation of the placenta.It can also inhibit the apoptosis of trophoblast cells to reduce the incidence of abortion,and the adverse reactions are rare,so it is safer to use during pregnancy.This paper aims to investigate the effect of low molecular weight heparin therapy during pregnancy on the pregnancy outcome of recurrent abortion patients with autoimmune subclinical hypothyroidism for better clinical application.Methods:Retrospective analysis was conducted on the patients who underwent prenatal examination and termination of pregnancy in Qingdao Municipal Hospital from 2016 to2022,and data were collected.According to the inclusion and exclusion criteria,a total of 164 recurrent abortion patients with autoimmune subclinical hypothyroidism found in early pregnancy were screened out.According to the medication regimen,patients were divided into levothyroxine treatment group(104 cases)and levothyroxine combined with low molecular weight heparin treatment group(60 cases).The general situation,fetal live birth rate,abortion rate,incidence of fetal distress,premature delivery and other obstetric complications,thyroid function and coagulation function before and after treatment were compared between the two groups.Statistical software SPSS26.0 was used for data statistics and analysis,and it was considered that p<0.05 was statistically significant.Results:1.General information of patientsA total of 164 patients with recurrent abortion complicated with autoimmune subclinical hypothyroidism were included in this study,including 104 patients in the levothyroxine treatment group,ranging in age from 25 to 45 years old,with an average age of 33.10±1.19 years old.A total of 60 patients were treated with levothyroxine combined with low molecular weight heparin.The patients ranged in age from 25 to 43 years old,with an average age of 33.34±1.86 years old.There was no significant difference in mean age between the two groups(p>0.05).2.Clinical dataA total of 164 patients with recurrent abortion complicated with autoimmune subclinical hypothyroidism were included in this study,including 104 patients in the levothyroxine treatment group and 80(76.92%)who delivered successfully.Of 60 patients treated with levothyroxine combined with low molecular weight heparin,58(96.67%)gave birth successfully.There were statistical differences in live birth rate and abortion rate between the two treatment groups(p < 0.05).By comparing the pregnancy complications and delivery modes between the two groups,it was found that the incidence of pregnancy hypertension,fetal distress and oligohydramnios or oligohydramnios in the levothyroxine treatment group was significantly higher than that in the levothyroxine combined with low molecular weight heparin treatment group,and the difference between the two groups was statistically significant(p < 0.05).There was no statistical significance in the rates of cesarean section,vaginal delivery and other obstetric complications between the two groups(p>0.05).The statistical analysis and analysis of thyroid power and coagulation indexes between the two groups showed that there were statistical differences in the D-dimer data of coagulation indexes between the two groups(p < 0.05),but there were no statistical differences in the PT,APTT,fibrinogen and thyroid power(TSH,FT3,FT4)of coagulation indexes between the two groups(p>0.05).Conclusions:In recurrent abortion patients with autoimmune subclinical hypothyroidism,administration of low molecular weight heparin during pregnancy can increase the fetal live birth rate,reduce the abortion rate,reduce the incidence of obstetric complications during pregnancy,reduce blood D-dimer levels,and stabilize the coagulation system.