HRT for perimenopause: can you start before periods stop?

My friend said HRT causes cancer. My aunt said it saved her life. My doctor said, let's look at the numbers.

Good doctor. Let's do exactly that: what hormone therapy is, what it helps, what the big study really found, the risks in plain numbers, and how to choose. One topic a week, every number sourced. Subscribe, and the next one finds you.

Hormone therapy replaces the estrogen your ovaries are making less of. If you still have a uterus, you also take a progestogen, because estrogen on its own can thicken the uterine lining. Estrogen comes as a patch, a gel, a spray or a tablet. The progestogen can be a tablet, such as micronized progesterone, or a hormonal IUD. Separate from all of this is low-dose vaginal estrogen, a cream, tablet or ring for dryness and bladder symptoms, which works mostly where it's applied.

For hot flashes and night sweats, it's the most effective option: estrogen cuts how often they happen by about seventy-five percent. Guidelines also list sleep problems, and low mood and anxiety that start with menopause, among the symptoms it can relieve. For vaginal dryness, low-dose vaginal estrogen improves symptom severity by sixty to eighty percent. And it protects bone. In SWAN, women lost more than seven percent of their spine bone density in just the three years around the final period. While you take hormone therapy, your risk of fractures is lower.

So why are so many women afraid of it? In 2002, the Women's Health Initiative trial stopped early, headlines linked hormone therapy with breast cancer and heart attacks, and use dropped sharply around the world. But that trial gave an older type of estrogen tablet, with a synthetic progestin, to women whose average age was sixty-three, older than most women who start it for symptoms. Eighteen years of follow-up later, the picture is calmer. Deaths from any cause: 27.1 percent with hormones, 27.6 percent with placebo. No difference in deaths from heart disease or cancer. And women who started in their fifties did better than women who started in their seventies.

Here are the risks that remain, in real numbers. Breast cancer. With combined hormone therapy, the UK health service estimates around five extra cases for every thousand women who take it for five years. With estrogen alone, for women without a uterus, there's little or no increase. Blood clots. Estrogen tablets raise the risk, by about one and a half times in a study of more than eighty thousand women with clots. Patches, gels and sprays didn't raise it at all. Put together, in the big US trial, combined hormones in women aged fifty to fifty-nine meant twelve extra serious health events per ten thousand women a year, about one in eight hundred. With estrogen alone in that age group, there were nineteen fewer. For healthy women under sixty, or within ten years of their last period, the Menopause Society finds the benefits generally outweigh the risks.

How it's given matters. If you have risks for clots, such as a past clot or a higher weight, patches, gels and sprays are usually preferred. Start with the lowest dose that controls your symptoms. If you have a uterus, the progestogen matters too: micronized progesterone or a hormonal IUD are common choices. You'll also hear about bioidentical hormones. Regulated bioidentical estradiol and progesterone already exist on prescription. Custom-compounded creams and pellets are different: they aren't FDA-approved, and their doses aren't standardized. In a US survey, eighty-six percent of women didn't know that.

Hot flashes often start to ease within days to weeks, and it can take up to three months to feel the full effect. Breast tenderness, headaches and spotting are common at first and usually settle within about three months. Irregular spotting can last three to six months on a new regimen. If side effects don't settle, the dose, the type or the route can be changed. Give each change three months, and keep a short symptom diary for your review.

Talk it through carefully with your doctor if you've had breast cancer, a blood clot, a stroke or liver disease. And on hormone therapy, a few things need checking promptly: pain or swelling in one leg, a new breast lump, or bleeding that continues after six months. Chest pain or sudden breathlessness: call 911.

Hormone therapy isn't right for everyone, and it isn't the danger the old headlines made it. It's a decision you can make with real numbers. Find your stage in two minutes at perimenostage.com, and bring your questions to your doctor.

My friend, my aunt, my doctor. The numbers were the tiebreaker.

Next week: lifting weights in perimenopause, and what one trial found for hot flashes. Subscribe so it finds you.