Transdermal Estrogen Now Top Choice for Menopause Hormone Therapy

Nearly one in five Danish women over age 40 — 454,592 out of 2,350,335 tracked over 24 years — used systemic menopausal hormone therapy at least once. Yet the way they take it has shifted dramatically: by 2024, 75% of new users started with transdermal estrogen rather than pills, according to a nationwide drug utilization study published in the British Journal of Clinical Pharmacology. That single statistic captures a quiet but consequential change in how menopause is treated.

A Nationwide Shift From Tablets to Skin-Delivery Systems

Researchers led by Hanna K. Wood-Kurland at Copenhagen University Hospital, together with colleagues at the Danish Cancer Institute and the University of Copenhagen, analyzed prescription records for every Danish woman over 40 between 2000 and 2024. It is one of the most complete pictures of hormone therapy use available anywhere, because Denmark’s national registries capture essentially all prescriptions redeemed.

The headline finding is not just that use declined — prevalence fell from 107.7 per 1,000 women in 2000 to 17.8 per 1,000 in 2024, and in women aged 51–60 from 191.0 to 33.8 per 1,000. It is how the remaining users get their estrogen. Transdermal initiation climbed from 56% of new users in 2022 to 63% in 2023 and 75% in 2024. Pills, once the default, are now the minority choice among new starters in Denmark.

One more detail deserves attention. Among women who began therapy before 2015, 37% used it for less than one year cumulatively. Some of that reflects side effects or symptom resolution; some likely reflects women quitting due to fear of risks, misinformation, or cost. Duration of use matters, because the benefits of estrogen for bone density and symptom control depend on sustained exposure.

Why the Route of Administration Changes the Biology

Estrogen is the same molecule whether it arrives as a tablet, patch, gel, or spray — but the path it takes through your body changes what it does along the way. Oral estradiol is swallowed, absorbed through the gut, and delivered directly to the liver via the portal vein before reaching the general circulation. This is called first-pass metabolism.

In the liver, that concentrated estrogen exposure triggers several changes. The organ increases production of clotting factors — including fibrinogen and factors VII and VIII — which raises the theoretical risk of venous thromboembolism. Oral estrogen also raises triglycerides and stimulates production of sex hormone-binding globulin (SHBG), a protein that mops up free estradiol, potentially blunting its activity in tissues. It can also increase C-reactive protein, a marker of inflammation, something we covered in detail in our article on the estrogen-inflammation link.

Transdermal delivery sidesteps all of this. Estradiol absorbed through the skin enters the bloodstream directly, spreading through the body before reaching the liver at much lower, diluted concentrations. Observational data consistently show lower venous thrombosis rates with transdermal compared with oral estrogen, which is a major reason guidelines increasingly favor patches and gels for women with elevated clot risk, obesity, migraine with aura, or smokers — though individual risk assessment is always needed.

What This Means for Women Considering Therapy

The Danish data reflect a growing international preference. The 2024 uptick in incidence — from 4.3 to 8.5 new users per 1,000 person-years nationwide, and from 9.3 to 20.2 in women aged 51–60 — suggests menopause is being discussed more openly, and that women who previously went untreated are now seeking care. This parallels the arrival of non-hormonal options such as elinzanetant for hot flashes, which we examined in a recent review.

Honest caveats apply. Denmark’s national formulary and reimbursement policies shape prescribing patterns, so transdermal dominance there may partly reflect cost and availability rather than pure patient choice. The study also measured prescriptions redeemed, not symptoms, satisfaction, or clinical outcomes — so it cannot tell us whether the shift produced better results, only that it happened. And for women whose ovaries are removed surgically, the risk-benefit calculus differs, as does the urgency of starting estrogen, a topic we explored in our piece on surgical menopause and cardiovascular outcomes.

Practical Considerations When Choosing a Route

If you are weighing options, the evidence points to a few practical questions worth raising with your clinician:

• Clot and cardiovascular risk factors: Obesity, prior blood clots, smoking, migraine with aura, or elevated triglycerides generally tilt the decision toward transdermal estradiol.
• Consistency of dosing: Patches deliver steady hormone levels for three to seven days; gels and sprays require daily application and care to avoid transferring hormone to others through skin contact.
• Uterine protection: Women with an intact uterus need progestogen alongside estrogen — via patch, pill, or an intrauterine system — regardless of the estrogen route, to protect the uterine lining.
• Dose flexibility: Gels and sprays allow fine dose adjustments, which helps when titrating to symptom relief at the lowest effective dose.

Notably, a related 2026 review in Current Cardiology Reports on androgens and cardiovascular disease reminds us that estrogen does not act in isolation — other hormones circulating after menopause, including testosterone and DHEA, follow J-shaped curves with mortality, and exogenous hormone risks depend heavily on dose. Route and dose are two levers that clinicians can adjust together.

Conclusion

Denmark’s registry data show a decisive turn: three-quarters of women starting hormone therapy in 2024 chose transdermal estrogen. The biological logic — avoiding the liver’s first-pass effects on clotting proteins and lipids — supports that shift, especially for women with clot-related risk factors. Whether you take estrogen through skin or by mouth, the Danish experience suggests one thing clearly: therapy works best when it is sustained, appropriately dosed, and matched to your individual risk profile.

Frequently Asked Questions

Is transdermal estrogen safer than oral estrogen?

Observational studies consistently show lower rates of blood clots with transdermal forms, largely because transdermal estradiol avoids concentrated exposure to the liver that boosts clotting-factor production. Absolute risk with either route remains low for most healthy women, so the choice should reflect your personal risk factors.

Does a patch deliver the same amount of estrogen as a pill?

Yes, roughly — but the blood levels differ in shape. Transdermal delivery produces a steadier, more physiologic estradiol profile, while oral doses must be higher to compensate for the fraction the liver metabolizes away before reaching circulation.

Why did so many women in the study stop therapy within a year?

The data show 37% of women starting before 2015 used hormone therapy for less than one year cumulatively. Reasons likely include symptom relief, side effects, and fear of reported risks — often without individualized counseling about duration or route.

Can I switch from oral to transdermal estrogen if I have risk factors?

Yes, switching routes is common and usually straightforward, though dose equivalents need adjustment and any transition should be supervised by your clinician. If you develop a clot-related risk factor like new obesity or migraine with aura, raising the question of switching is worthwhile.

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