October 2022
In this month's Did You Know? series, Chief Science Officer Beth DuPriest, PhD discusses how menopausal changes are interestingly similar to lactational changes. Learn how these two periods of a woman's life cycle are similar, and supportive ways to treat symptoms, including non-pharmacological options. Have a question about vaginal biome science? Submit yours here and your answer may be featured in an upcoming newsletter.
Q: How are menopausal changes similar to lactational changes?
A: Menopause is a stage of life that modern women can expect to go through…but that doesn’t mean it’s always been that way. In evolutionary history – and in nearly all members of the animal kingdom – life literally ends when the reproductive age is complete. Somewhere along the line, human women began to outlive our reproductive years. The loss of estrogens and other hormones that occurs during menopause is therefore not exactly what nature intended, though it is definitely a natural process.
So what causes the symptoms of menopause, including vaginal dryness, thinned tissues, low libido, hot flashes, and sleeplessness? James Simon, Past President of the North American Menopause Society (NAMS), posits that everything that occurs in menopause is essentially the same as a woman would experience during lactation1 – just more intense and permanent. Lactation is a low-estrogen period of life, as is menopause. During lactation, vaginal tissues become drier and thinner (constituting genitourinary syndrome of menopause, GSM) as a way for the body to reduce energy expenditure. Similarly, libido is low during lactation…after all, from an evolutionary perspective, it is counter-productive to become pregnant again when you are nursing a baby, so why maintain vaginal tissue and sex drive if the body “shouldn’t” become pregnant?
What about hot flashes, sleeplessness, and anxiety? Hot flashes (vasomotor symptoms, VMS) occur when the cutaneous plexus opens up wide, delivering blood to the body surfaces. This creates sensations of heat and even sweating, but also actual heat exchange out of the body. If a woman with hot flashes is holding a baby, some of that maternal body heat will be transferred to the baby, increasing its chances of surviving cold nights. Sleeplessness and anxiety can be considered ways to increase vigilance to protect a baby and increase its survival as well. A mother who is super attentive, day and night, is more likely to keep predators away, and also less likely to smother her baby during the night.
Menopause symptoms are not easy to live with. But for most women, they are treatable with hormone-replacement therapy, and for most women, they last only a few years. Maybe it helps to understand why these symptoms exist…and if not, at least you have an interesting point of conversation for your next dinner party.
The recent (2022) position paper from NAMS2 states that hormone therapy is the most effective treatment for VMS and GSM. For women without contraindications (history of breast cancer, venous thromboembolism, etc.), hormone therapy seems to be favorable for women under age 60 who have experienced symptoms for less than 10 years; after this point, the risks increase and no longer outweigh benefits. Low-dose vaginal estrogen, vaginal DHEA, or oral ospemifene are recommended for GSM symptoms not relieved by non-hormonal therapies.
Not mentioned in the position paper are the non-pharmacological options for women, including vaginal moisturizers. Women who choose to use over-the-counter vaginal products should be guided to select iso-isomotic gels with an appropriate pH (between 3.5 and 4.5) to avoid further damage to vaginal tissues.
References
1. Pollycove R, Naftolin F, Simon JA. The evolutionary origin and significance of menopause. Menopause. 2011;18(3):336-342. doi:10.1097/gme.0b013e3181ed957a
2. The 2022 hormone therapy position statement of The North American Menopause Society. Menopause. 2022;29(7):767-794. doi:10.1097/GME.0000000000002028