Effects of low-molecular-weight heparin and aspirin in recurrent pre-eclampsia: A stratified cohort study

Objective: To evaluate the effects of low-molecular-weight heparin (LMWH) combined with low-dose aspirin (LDA) in pregnant women with a history of pregnancy-related hypertensive disorders.

Methods: In the current retrospective stratified cohort study, 33 women with previous hypertensive disorders of pregnancy treated with LMWH and LDA were compared with 37 control women who did not undergo LMWH or LDA treatment. Rates of pre-eclampsia recurrence, placental abruption, and other adverse outcomes for the fetuses and pregnant women were compared in the two groups.

Results: The pre-eclampsia recurrence rates were 12/33 (36.4%) in the LMWH + LDA group and 28/37 (75.7%) in the control group (P < 0.01). In stratified cohort analysis, pregnant women with a history of early-onset pre-eclampsia, a body mass index of at least 24 (calculated as weight in kilograms divided by the square of height in meters), and aged less than 35 years benefited from LMWH + LDA treatment. In women with chronic hypertension or a history of placental abruption there was no protective effect. There were no significant differences in other adverse outcomes such as placental abruption and small size for gestational age in fetuses or pregnant women in the two groups.

Conclusion: Administration of LMWH + LDA only lowered the risk of pre-eclampsia recurrence in subgroups of pregnant women with a history of pregnancy-associated hypertensive disorders.