A very common question in my office surrounds the conversation about testing hormones. Now, anyone who has sat in my office knows the story I’m about to tell you.

Hormones are complicated things to test. They change every single hour, of every single day. We have a 28 (ish) day cycle, and we need to stop think that we’re supposed to be experiencing the same thing every day. So, in some cases they are indicated to test. If we need to understand if you’re ovulating, testing can be important. But sometimes, we don’t necessarily need to test your hormones to tell us what’s going on.

It’s important to test your hormones on specific days of your cycle because to get a really good understanding of levels and how they’re affecting your symptoms, you have to test and compare with where they should be based on the timing of your cycle. Otherwise when you simply test on the day you happen to be in the doctor’s office getting an exam, your levels may be just fine for that particular day.

So, here’s when you should be testing your hormones; and here’s what you maybe don’t need to test for. And, for clarity’s sake, you should consider day 1 to be the first full day of your bleed.

Fertility:

When it comes to ovulation, understanding your levels of FSH and LH are very important. These should be tested on day 3 of a 28 day cycle. If you have a longer or shorter cycle, talk to your medical practitioner about when you should be testing. FSH and LH can help us understand how the brain is talking to the ovaries and the hormones can help us know how the ovaries respond to that message.

Estrogen:

Estrogen, or estradiol, should be tested on day 3 of your cycle as well. As we transition into menopause, estrone or E1 becomes the most common circulating estrogen. This is important to understand because, depending on the phase of life you are in, your estrogen levels and the type of estrogen will vary. If you are in a phase of life where you should be having periods, you need to check estradiol.

In some cases, we also test estradiol about 5-7 days after your ovulation. Evaluating your estrogen levels, especially in relation to progesterone during the luteal phase can help you identify if your symptoms like weight gain, irritability, and heavy periods are related to a hormone imbalance.

It is important to note that, when you test estrogen, it should always be high relative to progesterone. The idea of estrogen dominance is something I have always struggled with understanding, because during a menstrual cycle, your estrogen should always be higher than your progesterone.

Speaking of progesterone…

Progesterone levels are highest 5-7 days following ovulation, which is within our luteal phase (the second half of your cycle). This is why testing is recommended days 19-22 of a 28 day cycle. Progesterone can not be tested until after you ovulate. If you test beforehand you’ll get a low number (which is what you’re supposed to see!)

Testosterone:

Testosterone is highest in the morning and best tested between 7 a.m. and 10 a.m. As women, we need testosterone. When testosterone levels are low, this is often when we see low libido, fatigue, and even depression. And when they’re high, as we often see in polycystic ovarian syndrome (PCOS), women experience acne, irregular periods, and hair growth on the chin, chest and abdomen. Elevated testosterone can also lead to hair loss on the scalp. You can test testosterone at any point in your cycle, but we want to make sure it’s done early in the morning.

Thyroid:

The thyroid testing is something that can be done at any point in your cycle, but it’s important to do it first thing in the morning. Your thyroid levels will fluctuate a bit throughout the day, so we want to get an accurate picture in the morning. It’s important to stop any biotin supplements 72 hours before your blood test because they will skew the test results.