You’re awake at 3 a.m. for no obvious reason. Your patience is gone by 9 a.m. You walk into a room and forget why. You reread the same email three times and still don’t get it.

So you blame stress. Work. Kids. Life.

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And sure, life is doing a lot right now. But for many women in their late 30s through early 50s, there may be another explanation hiding in plain sight: perimenopause. It’s the transition leading up to menopause, when hormone levels begin to shift.

The tricky part is that perimenopause doesn’t always start with the symptoms people expect. Before hot flashes or noticeable period changes, women may experience sleep problems, fatigue, mood changes, trouble focusing or a general sense that something feels off. Night sweats, anxiety, headaches, joint aches and vaginal dryness can also be part of the picture.

Why women don’t always connect the dots

Perimenopause can be easy to miss because, for some women, it looks a lot like modern life.…