Quick answer: Progesterone is made mainly after ovulation and helps balance estrogen, supports a healthy luteal phase and early pregnancy, and has calming effects on sleep and mood. Low progesterone can show up as PMS, short or irregular cycles, spotting or trouble conceiving, and it falls in perimenopause. It is usually tested about seven days after ovulation.
Key takeaways
Progesterone is made mainly after ovulation and balances estrogen, supports the luteal phase and has calming effects on sleep and mood.
Low levels can show up as PMS, short or irregular cycles, spotting or trouble conceiving, and they fall during perimenopause.
Timing matters, so the test is usually drawn about seven days after ovulation.
What is Progesterone?
Progesterone is a steroid hormone made by the ovaries after ovulation (by the corpus luteum), and by the placenta during pregnancy. Smaller amounts come from the adrenal glands.
Why Progesterone matters
Progesterone prepares the uterine lining and supports early pregnancy, and it balances the effects of estrogen. It has a calming effect on the brain and sleep, and it supports bone and breast health.
Understanding your result
Reference ranges vary by lab, age and sex. Your provider interprets your result against the lab’s range and your overall picture, rather than chasing a single number. Functional labs are optional. They can be helpful in more complex cases.
What low Progesterone can mean
Low progesterone can reflect no ovulation (anovulatory cycles), including in PCOS, or perimenopause. High stress, under-eating or over-exercise, and thyroid problems or high prolactin can also lower it.
What high Progesterone can mean
High progesterone is normal after ovulation and in pregnancy, and it can also come from progesterone medications or creams.
What affects Progesterone
Progesterone is affected by cycle day and ovulation, stress and energy availability, thyroid and prolactin, and age.
Ways to support healthy levels
Eat enough and manage stress to support ovulation, and support thyroid health (see TSH). Track your cycles to time testing (see ), and discuss progesterone therapy with your provider if appropriate.
What does the research show about progesterone?
The BioCycle Study followed 250 healthy, regularly menstruating women aged 18 to 44 with up to 16 timed blood draws over two cycles, defining a cycle without ovulation as peak progesterone of 5 ng/mL or less. Even in their ovulatory cycle, women who had one cycle without ovulation had 22% lower progesterone and 25% lower estradiol than women who ovulated in both cycles. The study covered only two cycles and did not use ultrasound to confirm ovulation. (Hambridge et al., 2013)
The PROMISE trial randomly assigned 836 women with unexplained recurrent miscarriage to 400 mg of vaginal progesterone twice daily or placebo from early pregnancy through 12 weeks. Live birth rates were 65.8% with progesterone and 63.3% with placebo, a difference that was not statistically significant. The trial did not select women based on low progesterone levels, so it does not answer whether specific groups benefit. (Coomarasamy et al., 2015)
Overall, progesterone is most useful when timed to the second half of the cycle, and the research is clear that a single level has limits.
Progesterone and healthy aging
Progesterone supports sleep and bone renewal. Its decline in perimenopause is often among the first hormonal changes women notice.
When to see a naturopathic doctor
It may be time to see a naturopathic doctor if you have PMS, short cycles or spotting before periods, or trouble conceiving or pregnancy loss. The same is true if you have poor sleep or anxiety before periods, or perimenopause symptoms.
See a medical provider promptly for heavy bleeding, bleeding in pregnancy, or severe pelvic pain.
Progesterone at a glance
| Topic | What the article explains |
|---|---|
| Why it matters | Prepares the uterine lining and supports early pregnancy; balances the effects of estrogen; calming effect on the brain and sleep; and supports bone and breast health |
| What can affect it | Cycle day and ovulation; stress and energy availability; thyroid and prolactin; and age |
| Supportive habits discussed | Eat enough and manage stress to support ovulation; support thyroid health; track cycles to time testing; and discuss progesterone therapy with your provider if appropriate |
Questions to bring to your clinician
These questions can help you get the most out of your next visit.
When in my cycle should I have progesterone drawn so the result is meaningful?
How should I read my progesterone alongside the rest of my labs and my symptoms?
How often would it make sense to recheck my progesterone in my situation?
Which daily habits or medications could be influencing my progesterone before we retest?
Frequently asked questions
When should progesterone be tested?
About seven days after ovulation, often around day 21 of a 28-day cycle.
What does low progesterone mean?
It may mean ovulation did not occur or the luteal phase is short.
Can stress lower progesterone?
Chronic stress and under-eating can disrupt ovulation and lower progesterone.
Is progesterone cream effective?
Absorption varies. Discuss options with your provider.
Sources
- Coomarasamy A, et al. A Randomized Trial of Progesterone in Women with Recurrent Miscarriages. N Engl J Med 2015. PMID: 26605928. https://pubmed.ncbi.nlm.nih.gov/26605928/
- Hambridge HL, et al. The influence of sporadic anovulation on hormone levels in ovulatory cycles. Hum Reprod 2013. PMID: 23589536. https://pubmed.ncbi.nlm.nih.gov/23589536/
- Practice Committees of the American Society for Reproductive Medicine and the Society for Reproductive Endocrinology and Infertility. Diagnosis and treatment of luteal phase deficiency: a committee opinion. Fertil Steril 2021. PMID: 33827766. https://pubmed.ncbi.nlm.nih.gov/33827766/
- Santoro N. Perimenopause: From Research to Practice. J Womens Health (Larchmt) 2016. PMID: 26653408. https://pubmed.ncbi.nlm.nih.gov/26653408/
- Teede HJ, et al. Recommendations From the 2023 International Evidence-based Guideline for the Assessment and Management of Polycystic Ovary Syndrome. J Clin Endocrinol Metab 2023. PMID: 37580314. https://pubmed.ncbi.nlm.nih.gov/37580314/
- MedlinePlus: Progesterone Test
- NICHD: Infertility
This article is for educational purposes only and is not medical advice. It does not replace an individual evaluation. Talk with your healthcare provider before starting supplements or changing medications, especially if you are pregnant, nursing, or managing a health condition.
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