Hair loss early 40’s

Hello @jennyb77 and welcome to Mayo Clinic Connect. Hair loss can be a difficult problem to deal with. I found some information about hair loss on Mayo Clinic's website. Here is the link,
https://www.mayoclinic.org/diseases-conditions/hair-loss/diagnosis-treatment/drc-20372932, Especially look at the list about Preparing for Your Appointment." This gives you some good ideas as you approach doctors in the future.

I do encourage you to read this information about the different causes, as well as possible treatments. I'm just wondering if hair loss might run in your family. Have any of your relatives experienced this as well?

You do not mention your general health, however, that can be a factor as well. As you can see, from the article on Mayo's website there are different physical reasons (other than just the thyroid) for hair loss. I recently saw a dermatologist as I've had hair loss as well. She mentioned that people who have had serious health problems like COVID, surgeries, etc. often experience hair loss several months after they recover. Some medications can also affect hair loss. Have you considered seeing a dermatologist?

If you get no answers there and you still feel concerned, consulting an endocrinologist could also offer you some answers.

As I'm another hair loss patient, I would enjoy hearing from you again. Will you post updates as you learn more?

Had the typical female hair loss pattern with my hair thinning out in the center on top of my head. My dermatologist tested me, and found that i had rather high testosterone. They prescribed finasteride, and had a compound paste made, consisting of dutasteride and Minoxidil. I had to apply this paste every night, and leave it in as long as possible the next day. It took about 3 r 4 month, and all my hair grew back, and I have my full head of hair again.