Prophylactic Effects Of Low-molecular-weight Heparin And Aspirin In Recurrent Pre-eclampsia:A Stratified Cohort Study

OBJECTIVES:To evaluate the effect of low-molecular-weight heparin(LMWH)combined with low-dose aspirin(LDA)in varies subgroups of pregnant women with a history of pregnancy related hypertensive disorders(HDs),and to assess the effect of this medication on other adverse outcomes for the fetuses and pregnant women.METHODS:In this retrospective stratified cohort study,we prophylactically treated 33 women with previous HDs of pregnancy with LMWH and LDA during the initial 12 weeks and compared them with 37 control women who did not undergo either LMWH or LDA treatment.Recurrent rates of pre-eclampsia,occurrence rate of placental abruption,small for gestational age(SGA),and other adverse outcomes for fetuses and pregnant women were compared between the two groups.RESULTS:There were significant differences in the recurrent pre-eclampsia rate between the groups:12/33(36.4%)in the LMWH+LDA group vs.28/37(75.7%)in the control group(P<0.01).There were no significant differences in occurrence rate of placental abruption,SGA,and other adverse outcomes for fetuses and pregnant women between two groups(P>0.05).Stratified cohort analysis showed that pregnant women with a history of early-onset pre-eclampsia and a body mass index(BMI)≥24 kg/m2 benefitted from treatment(P<0.05).Additionally,women with chronic hypertension,a history of placental abruption,or previous intrauterine death showed no protective effect(P>0.05).There were no significant differences in other adverse outcomes such as placental abruption and SGA on fetuses and pregnant women.CONCLUSIONS:Prophylactic administration of LMWH combined LDA lowered the risk of recurrent pre-eclampsia,but did not reduce the risk of placental abruption,intrauterine death and SGA,and meanwhile did not increase the risk of postpartum hemorrhage.Prophylactic administration of LMWH combined LDA lowered the risk of recurrent pre-eclampsia in certain subgroups of pregnant women with a history of pregnancy HDs.This selective effect could be attributable to differences in pathogenesis and was likely dependent on the different stages of HDs of pregnancy.Our results could be useful as a guide to clinical medication.