Your Menstrual Cycle & Hormone Testing

When our Naturopathic Doctors recommend hormone testing we know the process can come with questions and some confusion so we want to make sure that you feel confident and empowered in the journey to getting to the root cause of your concerns. Below is a summary of how to best track your cycle to time sample collection optimally and how to ensure we get the most accurate information so that you don’t waste time or money.

Overview of Menstrual Cycle for Hormone Testing

Day 1 — this is the first day you see bright red blood.

Day 14 — this is when women are typically told they ovulate, but that’s not true for everyone or every cycle. But we use this as a baseline when discussing lab tests and timing.

Day 28(ish) — not everyone has a 28-day cycle. However, you’ll often hear the menstrual cycle talked about in terms of 28 days. This is where your hormones drop if you don’t get pregnant. If you’re tracking your period and you know that you have a shorter or longer cycle we can adjust testing timing appropriately.

Back to Day 1 – this is when you’ll once again see blood.

What is cycle length?

Cycle length is the time from the first day of your period to the first day of your next one.

When to collect samples:

If you are doing the DUTCH test you will be instructed to collect samples between day 19 and 21 of your cycle.

If we are testing hormones using other methods (ie. serum/blood, saliva) you may be instructed to collect your samples on different days depending on what we are assessing.

When using these methods we often test on varying days depending on the hormone:

• Estradiol, Follicle Stimulating Hormone (FSH) & Luteinizing Hormone (LH) – tested on cycle day 3
• Progesterone – tested 5-7 days following ovulation
• Testosterone – accurately tested any day of the cycle but is best done as early in the morning as possible when levels are highest

If you haven’t been tracking your cycle we often recommend tracking it using a simple app like Clue, Flo or P Tracker Lite for 3 cycles to ensure that we are timing testing appropriately.

Why we don’t recommend testing sex hormones while on hormonal birth control

While on hormonal birth control you should not ovulate and you don’t have a period. Instead, you have a medication-induced withdrawal bleed that isn’t actually a period. While using hormonal birth control the values that would be measured would not accurately reflect your natural hormone balance or production.

What about other hormones?

Your sex hormones aren’t the only ones you may need to look at to understand the cause of your hormone symptoms.

Insulin – fast before testing and collect sample in the morning. Note that any biotin supplements should be avoided at least 72 hours prior to testing. You may also find testing post-prandial insulin 2 hours after eating valuable.

Cortisol - Cortisol blood tests are best performed in the morning but we also find assessing cortisol values throughout the day valuable as well (cortisol curve). For the most comprehensive assessment of adrenal function, salivary or urinary cortisol is preferred over serum values.

DHEA – can be tested any time of month and is typically measured alongside cortisol.

Thyroid hormones – thyroid testing is best done in the morning and can be done at any point of your cycle. Like with insulin testing, you will want to stop taking any supplements containing biotin at least 72 hours in advance of sample collection. We also recommend testing the following for a thorough assessment of thyroid health and function:

• Thyroid-stimulating hormone (TSH)
• Free T4 and T3
• Thyroid binding globulin (TBG)
• Thyroid antibodies – thyroid peroxidase (TPO) and thyroglobulin (TgAb)
• Thyroid receptor antibodies
• Reverse T3

*The goal here is to measure at minimum TSH, Free T4, and T3 so you get a picture of what the brain says, how the thyroid responds, and the body’s ability to activate the thyroid hormone you actually use.⁠