Population health analysis of birth outcomes after iliofemoral thrombosis and stenting

Patients with iliofemoral thrombosis, including May-Thurner syndrome, often require stenting, but birth outcomes in this population are unclear due to the need for long-term studies.  The purpose of this study was to determine birth outcomes in female patients with iliofemoral thrombosis who received venous stents using population health data.

Materials and Methods:

Merative MarketScan data from 2008-2021 were filtered for iliofemoral thrombosis and pelvic venous stenting using CPT and ICD codes. A comparison group of patients with iliofemoral thrombosis without stenting was assembled, along with age-matched control women. Pregnancy events (live births, ectopic pregnancies, abortions, and stillbirths) were analyzed using chi-square tests, while two-proportion z-tests were used to compare abortion rates before and after intervention in both groups.

Results: We identified 883 stented women, 33,751 non-stented women, and 3.9 million control women. After random downsampling, groups were age-matched (p = 0.85). No significant differences were found in live birth, ectopic, or stillbirth rates between the groups before or after thrombosis or stenting. However, abortion rates significantly increased after stenting (p = 0.003) and after thrombosis diagnosis in the non-stented group (p < 0.001).

Conclusion: These findings suggest that in women who have iliofemoral thrombosis, stenting itself does not affect the rate of live birth versus ectopic pregnancy, abortion, or stillbirth.  The rate of abortion increased after thrombosis or stenting, but was not different between stented versus non-stented patients, suggesting that factors beyond stenting could be a driver.