The Sex Surge Smoking Gun
…or one of them, at least.
You ever read something that changed your life? Maybe it was a book or a paragraph or some bit of information that just changed your whole world? It changed your heart or opened your eyes? That happened to me this past week.
For the last two weeks I have been cleaning up the last, tiniest details of the Sex Surge® book manuscript. Making sure I haven’t missed any commas, or spelled it “form” instead of “from,” looking for missing parenthesis marks, etc. But I’ve also been double-checking my research and seeing if there was anything new on the subject of women’s hormones, testosterone, and behavioral changes associated with those things.
As you know, I have long suspected that the Sex Surge is brought on by some kind of shift in testosterone. Not enough to masculinize a woman (giving her large muscles, facial hair, and more chiseled features), but just a little shift that would produce the sexual and sensual outcomes we see in the Surge. I’ve been asked if it isn’t some shift in estrogen or progesterone that causes the symptoms. And while those two hormones do sometimes fit some of the profile of thoughts and behaviors we see in the Sex Surge, they don’t answer all of them. Testosterone does, though. So, it’s always been my top suspect.
Well, I started reading a journal article that I had seen mentioned in several places, but never thought to read for itself. Admittedly, the title is “The Impact of Aging on Sexual Function in Women and Their Partners.” I thought it was going to be about all the difficult stuff that happens as women age. And it sort of was depressing, but forgive me for pre-judging a thing before I actually read further. Because further in there is this paragraph:
“Testosterone is bound to albumin and sex hormones-binding globulin (SHBG). During the time of the peri-menopausal transition, as estrogen levels are declining, women also experience a decrease in SHBG, which binds both estrogen and testosterone and, in fact, tends to bind testosterone more than it does estrogen. Some peri-menopausal women will notice an increase in sexual desire and activity, perhaps because the declining levels of SBHG frees up more testosterone.” [emphasis mine]
[[Kingsberg, S.A. (2002). The Impact of Aging on Sexual Function in Women and Their Partners. Archives of Sexual Behavior. 31(5), 431-437.]]
What does this mean? Well, let’s say the sex hormones-binding globulin (SHBG) is like a trolley or shopping cart. And, in women, it goes around collecting cheese (estrogen) and crackers (testosterone) so no one else can buy them. But it’s a little better at catching the crackers inside the cart; the testosterone sticks better or is easier to catch somehow. When peri-menopause comes around, the cart gets smaller- the amount of SHBG in a woman’s blood goes down. And because the cart is smaller, it can’t catch as much cheese and crackers. And because the cart is better at catching and holding the crackers, when it gets smaller, there are even less crackers in the cart, and therefore even more crackers hanging out in the grocery store. So, now there are more crackers available than there have been before. Which is to say, because the SHBG goes down, there is more estrogen, but potentially way more testosterone, than in the past. And the author of the paper is clear: that can lead to more sexual desire and activity on the part of the peri-menopausal woman.
I did a big-eyed, jaw drop when I read that, honestly. I was thinking, “Holy shit. There it is. There it fucking is. The sex surge fucking exists bio-chemically.”
Now. This doesn’t explain everything about the Surge. It doesn’t explain why some women in their thirties get it. There is usually some hormonal shift that the younger women I’ve talked to can name- finishing breastfeeding is the most common change mentioned. But the Sex Surge in younger women may not necessarily have to do with the sex hormones-binding globulin. There are also plenty of women who experience the Surge well after they have finished menopause. The data from this article doesn’t exactly explain those cases, either. And it doesn’t adequately explain why many women (but not all) I talk to notice the onset of symptoms as initially happening around their time of ovulation. So, it’s not the entire answer or explanation for the Sex Surge. But it’s a big one.
So, these are the words that changed my life this past week. I felt validated when I read them. I felt like we had something to search for- or another baseline hormone we need to check at age 25 so we have data for when things change later in life. But it felt really damn good to find this- and now to be able to share it with you. I hope it feels cool to you, too.
And big thanks to the non-Surge readers who are still here. I deeply appreciate your willingness to stick with this and be supportive of your Surge (and fellow peri-menopause) sisters.
Big love from hormone central and the book design desk-
Joanna :: xoxo