Progestogens and venous thromboembolism in menopausal women: an updated oral versus transdermal estrogen meta-analysis.
Level 2 - randomized trial
Meta-analysis synthesizing clinical and observational evidence on hormone therapy routes, regimens, and venous thromboembolism risk.
PubMed 29570359 · doi:10.1080/13697137.2018.1446931
What was done
The authors conducted an updated meta-analysis evaluating venous thromboembolism (VTE) risk in menopausal hormone therapy users. The analysis assessed differences by route of estrogen administration (oral versus transdermal), hormonal regimen (estrogen-only versus opposed), and specific progestogen molecules.
What was found
Among women using estrogen-only therapy, oral preparations increased VTE risk (RR 1.48, 95% CI 1.39–1.58), whereas transdermal preparations did not (RR 0.97, 95% CI 0.87–1.09). In opposed transdermal regimens, micronized progesterone was not associated with increased risk (RR 0.93, 95% CI 0.65–1.33), whereas norpregnane derivatives increased risk (RR 2.42, 95% CI 1.84–3.18). Among opposed oral estrogen users, medroxyprogesterone acetate carried higher risk (RR 2.77, 95% CI 2.33–3.30) than other progestins.
Why it matters
These findings show that thrombotic risk depends heavily on the estrogen route of delivery and the specific progestogen class chosen. The data support preferential use of transdermal estrogen paired with micronized progesterone, particularly in women with elevated baseline VTE risk.
Limits
The abstract does not state the number of included studies, total participant sample size, or search parameters. Significant heterogeneity was present among opposed estrogen regimens, and specifics regarding hormone doses, treatment durations, and baseline patient risk factors are not reported.
Cited by
- supports Oral estradiol increases the risk of hypercoagulability compared to topical estradiol formulations.