Hormone replacement therapy (HRT) is typically prescribed for menopausal related symptoms. The most common complaints are vasomotor symptoms such as hot flashes and night sweats but many women also experience mood swings, sleep disturbance, urogenital atrophy, anxiety, depression and fatigue. Even though there are many therapeutic options for addressing these individual symptoms, HRT tends to be the single option that will address all of the symptoms, assuming there aren’t any contraindications to its use.
There are numerous HRT formulations and delivery options. This article will attempt to provide clarity on this issue and will focus on the estrogen and progestin components. Progestin is typically used to prevent endometrial hyperplasia. Most of the menopausal related symptoms are relieved by the estrogen component. The most commonly used estrogens are oral micronized estradiol, conjugated equine estrogen, esterified estrogen, ethinyl estradiol and estrone sulfate. There is also a transdermal preparation, which is also an estradiol. There tends to be an even wider variety of progestins. The oldest one is medroxyprogesterone acetate, which was used in many of the initial combination HRT preparations. Others include the oral micronized progesterone known as prometrium as well as norethindrone acetate, levonorgestrel and drosperinone.
HRT is typically prescribed as cyclic or continuous. Cyclic regimens tend to have 21-28 days of estrogen and then 14 days of progestin. Consequently many women will experience a withdrawal bleed similar to a normal menses. Continuous HRT has a daily low dose of progestin, designed to prevent the growth of the endometrium thus eliminating the cyclic withdrawal bleeding that is mostly unwelcomed. HRT has a number of delivery routes. Formulations are designed to be used orally, transdermally and via internal routes. The preparations have evolved overtime but tend to include pills, patches, mists, sprays, gels, lotions, implants, strings and rings.
Alternate routes of HRT administration developed in response to the notorious 1st pass effect of oral estrogen. When taken by mouth, the estrogen concentrations in the liver are high leading to an increased hepatic production of substances such as lipids, clotting factors and binding globulins. This increased production leads to an increased risk of thromboembolic events and increased circulating lipid levels, which contributes to increased risk of cardiovascular disease. Delivery via other routes eliminates this 1st pass effect resulting in a lower risk of these problems.
The term “bioidentical hormones” has been introduced into the discussion of HRT and for many it translates into a safer or better product. However the term tends to be used interchangeably with “natural” hormones or compounded hormones. For many, natural means it is derived from plants. Equine estrogen is in a sense, natural since it is derived from animals and not synthesized in a manufacturing plant. Many women however object to the use of horse-derived estrogens. Compounded simply means that the batch of medication is made on demand rather than having a pre-made formulation. The advantage to compounding is that the dosage can be tailored to individual demand. Bio-identical means the medication is structurally identical to endogenous hormones. Many of the pre-made synthetic formulations such as estradiol and prometrium are bio-identical. So in fact conjugated equine estrogen is a natural product but not bio-identical.
The prescribing of HRT is not a simple endeavor. If you think you may need hormone replacement therapy it is important that you consult with an experienced clinician. The first step is assessing your need and your risks and the second is selecting the combination and type of therapy that best suits you.
I hope this article has provided you with information that will help you make wise choices, so you may:
Live healthy, live well and live long!