From the Research
Yes, a transdermal estrogen (estradiol) patch can be used in women with an intact uterus, but it must be combined with a progestogen medication to protect the uterine lining. Women with an intact uterus who use estrogen-only therapy face an increased risk of endometrial hyperplasia and cancer due to unopposed estrogen stimulation of the endometrial tissue 1. The standard approach is to use the estradiol patch (available in various doses from 0.025 to 0.1 mg/day) alongside either oral progesterone (typically 100-200 mg daily for 12-14 days per month in cyclic regimens, or 100 mg daily in continuous regimens) or another progestogen such as medroxyprogesterone acetate.
The most recent and highest quality study on this topic is from 2024, which found that most progestogens were able to prevent or treat hyperplasia, atypical hyperplasia, and even well-differentiated endometrial cancer 2. However, the study also noted that the choice of progestogen and dosing regimen can be difficult due to the variety of progestogens available and differences in their clinical effects.
The estradiol patch offers advantages over oral estrogen, including avoidance of first-pass liver metabolism, more stable hormone levels, and potentially lower risks of blood clots and stroke. However, some women may experience skin irritation at the application site or adhesion problems with the patch. The patch is typically applied to clean, dry skin on the lower abdomen or buttocks and changed according to the specific product instructions, usually once or twice weekly.
It's also important to note that the addition of progestogens, either in continuous combined or sequential regimens, helps to reduce the risk of endometrial hyperplasia and improve adherence to therapy 1, 3. The choice of progestogen and dosing regimen should be individualized based on the woman's medical history, symptoms, and preferences.
In terms of specific progestogen regimens, a study from 2018 found that the choice of progestogen for endometrial protection in combination with transdermal estradiol in menopausal women depends on various factors, including the type and dose of progestogen, as well as the individual woman's needs and preferences 4.
Overall, the use of a transdermal estrogen patch in women with an intact uterus requires careful consideration of the risks and benefits, as well as individualized counseling and monitoring to minimize the risk of endometrial hyperplasia and cancer. The key takeaway is that a progestogen medication must be used in combination with the estradiol patch to protect the uterine lining.