Progesterone
Progesterone stays under about 1 ng/mL before ovulation and rises after it. A committee opinion takes a level above 3 ng/mL about a week before a period as evidence of ovulation, and one study used 5. Luteal levels swing several fold within hours. In early pregnancy with pain or bleeding, very low levels went with pregnancies that did not continue.
- Status
- A blood test ordered by a clinician and also sold direct to consumers by some US laboratories. FDA classifies progesterone test systems as class I devices, exempt from premarket notification [1].
- Measures
- The amount of progesterone in blood, a hormone that starts to rise midway through the menstrual cycle and keeps rising in early pregnancy [2].
- Also called
- progesterone, serum progesterone, progesterone blood test, progesterone serum, P4, day 21 progesterone, mid-luteal progesterone, luteal progesterone
- Tested for
- confirming ovulation, fertility testing, irregular or absent periods, bleeding in early pregnancy, miscarriage risk, luteal phase, IVF monitoring, menopause
Strong several reviews agree · Moderate one review or consistent trials · Limited one or a few small studies · Untested no study in people, listed with what it rests on
Linked in research3
- ModerateLinked to non-viable pregnancy at low levels: with pain or bleeding and an inconclusive scan, progesterone under 3.2 to 6 ng/mL predicted it with 98.4% specificity.
- ModerateLinked to fewer pregnancies in IVF at both ends: raised progesterone before egg collection in fresh cycles, and luteal levels under 10 ng/mL in frozen transfers.
- LimitedOne study found a single progesterone of 5 ng/mL or above confirmed ovulation with 98.4% specificity and 89.6% sensitivity against ultrasound.
Reported risks0
No risks sourced yet.
Reference ranges
Each range is the one its source published, in ng/mL. Also reported in nmol/L. Where sources differ, each is shown.
US National Library of Medicine, MedlinePlus, women before ovulation
Females before ovulation in the menstrual cycle · [2]
| Range | What the source calls it |
|---|---|
| below 1 ng/mL | "normal" |
| 1 or above ng/mL | No name given |
Printed as less than 1 ng/mL or 3.18 nmol/L, so the range has no lower band. MedlinePlus states that ranges may vary slightly among laboratories and with the testing method, and names no assay [2].
US National Library of Medicine, MedlinePlus, women at mid-cycle
Females at mid-cycle, as the source labels it · [2]
| Range | What the source calls it |
|---|---|
| below 5 ng/mL | No name given |
| 5 to 20 ng/mL | "normal" |
| above 20 ng/mL | No name given |
Printed as 5 to 20 ng/mL or 15.90 to 63.60 nmol/L. The page does not say which days of the cycle the label mid-cycle covers. On the same page it states that progesterone starts to rise midway through the cycle, continues to rise for about 6 to 10 days, and then falls if the egg is not fertilized [2].
US National Library of Medicine, MedlinePlus, postmenopausal women
Postmenopausal females · [2]
| Range | What the source calls it |
|---|---|
| below 1 ng/mL | "normal" |
| 1 or above ng/mL | No name given |
Printed as less than 1 ng/mL or 3.18 nmol/L, so the range has no lower band. It names no assay [2].
Anckaert and colleagues, 2021, Roche Elecsys Progesterone III immunoassay, follicular phase
Women aged 18 to 37 with natural menstrual cycles, follicular phase · [3]
| Range | What the source calls it |
|---|---|
| below 0.05 ng/mL | No name given |
| 0.05 to 0.19 ng/mL | "reference interval" |
| above 0.19 ng/mL | No name given |
Printed as 0.159 to 0.616 nmol/L and converted here to ng/mL by dividing by 3.18. These are the 5th and 95th percentiles, so a tenth of the reference women fall outside them by construction. The 5th percentile and both ends of its confidence interval were 0.159 nmol/L, so the lower limit sits at the lowest value the study reported. The median was 0.212 nmol/L. From 85 women in the United States and Europe sampled about three times a week through one cycle, with cycle length standardized to 29 days and the luteinizing hormone peak placed at day 15. Two authors were employees of the assay's maker, which also funded medical writing [3].
Anckaert and colleagues, 2021, Roche Elecsys Progesterone III immunoassay, ovulation
Women aged 18 to 37 with natural menstrual cycles, ovulation phase · [3]
| Range | What the source calls it |
|---|---|
| below 0.055 ng/mL | No name given |
| 0.055 to 4.15 ng/mL | "reference interval" |
| above 4.15 ng/mL | No name given |
Printed as 0.175 to 13.2 nmol/L, the 5th and 95th percentiles in 81 women, and converted here to ng/mL by dividing by 3.18. The median was 1.81 nmol/L. See the follicular phase block for how the study was done [3].
Anckaert and colleagues, 2021, Roche Elecsys Progesterone III immunoassay, luteal phase
Women aged 18 to 37 with natural menstrual cycles, luteal phase · [3]
| Range | What the source calls it |
|---|---|
| below 4.12 ng/mL | No name given |
| 4.12 to 14.56 ng/mL | "reference interval" |
| above 14.56 ng/mL | No name given |
Printed as 13.1 to 46.3 nmol/L, the 5th and 95th percentiles in 85 women, and converted here to ng/mL by dividing by 3.18. The median was 28.8 nmol/L. The interval covers the whole luteal phase. Within it the median ran from 22.6 nmol/L early to 39.2 in the middle and 18.2 late. See the follicular phase block for how the study was done [3].
Schüring and colleagues, 2016, Siemens Advia Centaur immunoassay, follicular phase
Women aged 25 to 44 with regular cycles, follicular phase, days 3 to 5 after the start of a period · [4]
| Range | What the source calls it |
|---|---|
| below 1.03 ng/mL | "reference interval" |
| 1.03 or above ng/mL | No name given |
The 97.5th percentile in 139 women seen at one German university hospital, who had cycles of 25 to 35 days and had used no hormonal contraceptives for at least three months. The study reported no lower limit where the 2.5th percentile fell below the assay's limit of detection. The median was 0.47 ng/mL. Of everyone in the study, 96% were of European descent. The study was supported by the hospital's laboratory and by the assay's maker [4].
Schüring and colleagues, 2016, Siemens Advia Centaur immunoassay, luteal phase
Women aged 25 to 44 with regular cycles, luteal phase, days 21 to 23 after the start of a period · [4]
| Range | What the source calls it |
|---|---|
| below 1.14 ng/mL | No name given |
| 1.14 to 20.6 ng/mL | "reference interval" |
| above 20.6 ng/mL | No name given |
The 2.5th and 97.5th percentiles in 87 women. The median was 9.26 ng/mL. Samples were taken on fixed cycle days, not timed to each woman's ovulation. See the follicular phase block for how the study was done [4].
Schüring and colleagues, 2016, Siemens Advia Centaur immunoassay, postmenopausal women
Postmenopausal women aged 49 to 66 · [4]
| Range | What the source calls it |
|---|---|
| below 0.6 ng/mL | "reference interval" |
| 0.6 or above ng/mL | No name given |
The 97.5th percentile in 103 blood donors with no periods for at least 12 months, with no lower limit reported. The median was 0.17 ng/mL [4].
Schüring and colleagues, 2016, Siemens Immulite 2000XP immunoassay, follicular phase
Women aged 25 to 44 with regular cycles, follicular phase, days 3 to 5 after the start of a period · [4]
| Range | What the source calls it |
|---|---|
| below 0.97 ng/mL | "reference interval" |
| 0.97 or above ng/mL | No name given |
The same 139 women's samples measured on a second platform in the same run, with no lower limit reported. The median was 0.46 ng/mL. See the Advia Centaur follicular phase block for how the study was done [4].
Schüring and colleagues, 2016, Siemens Immulite 2000XP immunoassay, luteal phase
Women aged 25 to 44 with regular cycles, luteal phase, days 21 to 23 after the start of a period · [4]
| Range | What the source calls it |
|---|---|
| below 0.55 ng/mL | No name given |
| 0.55 to 17.5 ng/mL | "reference interval" |
| above 17.5 ng/mL | No name given |
The same 87 women's samples measured on a second platform. The median was 8.01 ng/mL. The lower limit is about half the 1.14 found for the same women on the Advia Centaur platform [4].
Schüring and colleagues, 2016, Siemens Immulite 2000XP immunoassay, postmenopausal women
Postmenopausal women aged 49 to 66 · [4]
| Range | What the source calls it |
|---|---|
| below 0.41 ng/mL | "reference interval" |
| 0.41 or above ng/mL | No name given |
The same 103 women's samples measured on a second platform, with no lower limit reported. The median was 0.1 ng/mL [4].
American Society for Reproductive Medicine committee opinion, 2026, evidence of ovulation
Women, on a sample taken about 1 week before the expected start of the next period · [5]
| Range | What the source calls it |
|---|---|
| 3 or below ng/mL | No name given |
| above 3 ng/mL | No name given |
The committee states that a progesterone concentration above 3 ng/mL provides presumptive and sufficient evidence of recent ovulation. It asks for the sample about 1 week before the expected period and not on a fixed cycle day such as day 21. It states that luteal progesterone can fluctuate sevenfold over a few hours, so a single value may be used to confirm ovulation but not to assess the quality of the luteal phase. The opinion does not name a term for a result of 3 or below [5].
Leiva and colleagues, 2015, threshold to confirm ovulation
Women with menstrual cycles, on a single sample taken on any day · [6]
| Range | What the source calls it |
|---|---|
| below 5 ng/mL | No name given |
| 5 or above ng/mL | No name given |
A single progesterone of 5 ng/mL or above identified cycles in which ovulation had been confirmed by ultrasound with a specificity of 98.4% (95% CI 96.0 to 99.5) and a sensitivity of 89.6% (85.2 to 92.9). From 102 women over 260 cycles in a European study, with one or two progesterone results per cycle. With a sensitivity of 89.6%, a result below 5 does not rule out ovulation [6].
US National Library of Medicine, MedlinePlus, pregnancy, first trimester
Pregnancy, first trimester · [2]
| Range | What the source calls it |
|---|---|
| below 11.2 ng/mL | No name given |
| 11.2 to 90 ng/mL | "normal" |
| above 90 ng/mL | No name given |
Printed as 11.2 to 90.0 ng/mL or 35.62 to 286.20 nmol/L. It names no assay or week of pregnancy [2].
US National Library of Medicine, MedlinePlus, pregnancy, second trimester
Pregnancy, second trimester · [2]
| Range | What the source calls it |
|---|---|
| below 25.6 ng/mL | No name given |
| 25.6 to 89.4 ng/mL | "normal" |
| above 89.4 ng/mL | No name given |
Printed as 25.6 to 89.4 ng/mL or 81.41 to 284.29 nmol/L. It names no assay [2].
US National Library of Medicine, MedlinePlus, pregnancy, third trimester
Pregnancy, third trimester · [2]
| Range | What the source calls it |
|---|---|
| below 48 ng/mL | No name given |
| 48 or above ng/mL | "normal" |
Printed as 48 to 150 to 300 or more ng/mL, or 152.64 to 477 to 954 or more nmol/L. The page gives no single upper limit, so only the lower limit is shown here. It names no assay [2].
US National Library of Medicine, MedlinePlus, men
Males · [2]
| Range | What the source calls it |
|---|---|
| below 1 ng/mL | "normal" |
| 1 or above ng/mL | No name given |
Printed as less than 1 ng/mL or 3.18 nmol/L, so the range has no lower band. It names no assay or age group [2].
Schüring and colleagues, 2016, Siemens Advia Centaur immunoassay, men
Men aged 20 to 68 · [4]
| Range | What the source calls it |
|---|---|
| below 0.86 ng/mL | "reference interval" |
| 0.86 or above ng/mL | No name given |
The 97.5th percentile in 220 blood donors who took no regular medication, with no lower limit reported. The median was 0.42 ng/mL. The maker's own interval, reprinted in the paper, was 0.28 to 1.22 [4].
Schüring and colleagues, 2016, Siemens Immulite 2000XP immunoassay, men
Men aged 20 to 68 · [4]
| Range | What the source calls it |
|---|---|
| below 0.82 ng/mL | "reference interval" |
| 0.82 or above ng/mL | No name given |
The same 220 men's samples measured on a second platform, with no lower limit reported. The median was 0.44 ng/mL [4].
What has been shown to move it
Shown to raise it1
Polycystic ovary syndrome
Shown to raise progesterone and endometrial thickness in women with PCOS. These are hormone and ultrasound measures, not pregnancy rates.
The numbers and sources
- Effect
- Across 22 studies (2,515 women), NAC was associated with higher progesterone (SMD 0.95, 95% CI 0.13 to 1.77) and thicker endometrium (SMD 0.58, 95% CI 0.10 to 1.06) than placebo and other drugs. Estradiol, SHBG and FSH did not differ [7].
- Population
- Women with PCOS, compared with placebo, metformin or clomiphene [7].
- Sources
- [7]
- Caveats
- Hormone and ultrasound measures, not pregnancy or live birth rates. Comparators were mixed.
How it compares with the reference method
Mixed results1
Between immunoassays, and against mass spectrometry
Small studies found two immunoassays read 5% and 19% above mass spectrometry, and agreement between assays ran from poor to excellent below 1.5 ng/mL.
The numbers and sources
- Compared with
- Liquid chromatography tandem mass spectrometry, and other immunoassays on the same samples
- Effect
- In samples from women having IVF, one immunoassay overestimated progesterone by 19% and another by 5% against mass spectrometry [12]. Across 413 samples measured with several assays, agreement was excellent overall, but in the ranges under 0.8, 0.8 to under 1.0 and 1.0 to under 1.5 ng/mL it varied between poor and excellent depending on the pair of assays [13]. In one reference interval study the same women's luteal samples gave a lower limit of 1.14 ng/mL on one platform and 0.55 on another [4].
- Population
- 28 serum samples from women in IVF cycles [12]. 413 blood samples taken during ovarian stimulation [13]. 87 women [4].
- Sources
- [12], [13], [4]
- Caveats
- Small studies from single centers. Differences are largest at the low levels found before ovulation, in men and after menopause.
Did not match the reference method2
Swings within a day in the luteal phase
One study found mid and late luteal progesterone swung between 2.3 and 40.1 ng/mL within 24 hours, often within minutes.
The numbers and sources
- Compared with
- Blood samples drawn every 10 minutes for 24 hours from the same women
- Effect
- In the early luteal phase progesterone was stable over 24 hours. In the mid and late luteal phase it fluctuated rapidly, from levels as low as 2.3 ng/mL to peaks of 40.1, often within minutes, following pulses of luteinizing hormone by 25 to 55 minutes [11]. The American Society for Reproductive Medicine states that luteal progesterone can fluctuate sevenfold over a few hours [5].
- Population
- 6 women with normal cycles, two each in the early, mid and late luteal phase [11].
- Sources
- [11], [5]
- Caveats
- One study of 6 women from 1984. It means a single luteal result can land on a peak or a trough.
Part of the luteal phase
One study found median progesterone peaked at 39.2 nmol/L, about 12.3 ng/mL, in the middle of the luteal phase and was less than half that late in it.
The numbers and sources
- Compared with
- The same women's samples from other parts of the cycle
- Effect
- Median progesterone was 0.380 nmol/L in the early follicular phase, 0.210 intermediate follicular, 0.188 late follicular, 1.59 at ovulation, 22.6 early luteal, 39.2 intermediate luteal and 18.2 late luteal. In ng/mL the three luteal medians are about 7.1, 12.3 and 5.7 [3].
- Population
- 85 women aged 18 to 37 sampled about three times a week through one natural cycle [3].
- Sources
- [3]
- Caveats
- One immunoassay study with authors employed by the assay's maker. A luteal result cannot be placed against a range without knowing how many days have passed since ovulation.
What studies tie it to
Linked in research3
Ovulation
One study found a single progesterone of 5 ng/mL or above confirmed ovulation with 98.4% specificity and 89.6% sensitivity against ultrasound.
The numbers and sources
- Effect
- In a study that tracked ovulation by ultrasound, a single serum progesterone of 5 ng/mL or above had a specificity of 98.4% (95% CI 96.0 to 99.5) and a sensitivity of 89.6% (85.2 to 92.9) for ovulation having occurred [6]. The American Society for Reproductive Medicine uses a lower figure, above 3 ng/mL about a week before the expected period, as presumptive and sufficient evidence of recent ovulation [5].
- Population
- 102 women over 260 menstrual cycles in a European multicenter study [6].
- Sources
- [6], [5]
- Caveats
- One study, a secondary analysis. The two sources use different cut points and neither is a reference interval. The committee opinion states that a single value does not assess the quality of the luteal phase [5].
Early pregnancy that does not continue, in women with pain or bleeding
Linked to non-viable pregnancy at low levels: with pain or bleeding and an inconclusive scan, progesterone under 3.2 to 6 ng/mL predicted it with 98.4% specificity.
The numbers and sources
- Effect
- In women with symptoms and an inconclusive ultrasound, a single progesterone below cut-offs of 3.2 to 6 ng/mL predicted a non-viable pregnancy with a pooled sensitivity of 74.6% (95% CI 50.6% to 89.4%) and specificity of 98.4% (90.9% to 99.7%). A low result raised the probability of a non-viable pregnancy from a median of 73.2% to 99.2%. In women with symptoms alone, a threshold of 10 ng/mL gave a sensitivity of 66.5% (53.6% to 77.4%) and a specificity of 96.3% (91.1% to 98.5%), raising the probability from 62.9% to 96.8% [7].
- Population
- 26 cohort studies with 9,436 women in the first 14 weeks of a spontaneous pregnancy, all with pain or bleeding [7].
- Sources
- [7], [2]
- Caveats
- Observational studies of test accuracy in women who already had symptoms, most of whose pregnancies were non-viable, so the figures do not describe pregnancy in general. A low level may mark a failing pregnancy and not cause it. MedlinePlus describes this use of the test as largely superseded by other tests [2].
Pregnancy in IVF cycles
Linked to fewer pregnancies in IVF at both ends: raised progesterone before egg collection in fresh cycles, and luteal levels under 10 ng/mL in frozen transfers.
The numbers and sources
- Effect
- In fresh IVF cycles, progesterone at or above 0.8 ng/mL on the day of the trigger injection went with a lower probability of pregnancy: odds ratios of 0.79 at 0.8 to 1.1 ng/mL, 0.67 at 1.2 to 1.4, 0.64 at 1.5 to 1.75 and 0.68 at 1.9 to 3.0. No such effect was seen in frozen-thawed or donor cycles [9]. Around frozen embryo transfer, among studies that used thresholds under 10 ng/mL, a level above the threshold went with more ongoing pregnancies or live births (relative risk 1.47, 95% CI 1.28 to 1.70) and fewer miscarriages (0.62, 0.50 to 0.77) in cycles using only vaginal progesterone and blastocysts [10].
- Population
- 63 studies of 55,199 fresh cycles, 9 studies of 7,229 frozen-thawed cycles and 8 studies of 1,330 donor cycles [9]. Cohort studies of women having frozen embryo transfer, searched to March 2021 [10].
- Sources
- [9], [10]
- Caveats
- Observational. These findings are for women in IVF treatment, most of them given hormones, and do not carry over to natural cycles. The second review found it uncertain whether thresholds of 10 ng/mL or above mattered, and calls for trials of whether raising a low level changes outcomes [10]. Assays disagree most at the low levels the first finding rests on (see Accuracy).
Checked, no link found1
Live birth in a trial of progesterone for bleeding in early pregnancy
One trial found vaginal progesterone for bleeding in early pregnancy did not significantly raise live births: 75% against 72% on placebo.
The numbers and sources
- Effect
- Women with vaginal bleeding in early pregnancy were given vaginal progesterone 400 mg twice daily or placebo until 16 weeks. A live birth after at least 34 weeks occurred in 75% (1,513 of 2,025) on progesterone and 72% (1,459 of 2,013) on placebo, a relative rate of 1.03 (95% CI 1.00 to 1.07, P = 0.08). Adverse events did not differ significantly [8].
- Population
- 4,153 women at 48 hospitals in the United Kingdom [8].
- Sources
- [8]
- Caveats
- A marker that tracks an outcome is not always one whose correction changes it. The trial enrolled women by bleeding and did not select them by blood progesterone or treat to a blood level, so it does not test raising a low result [8].
- Why limited
- This rests on one trial, of 4,153 people. Strength counts independent studies that agree, so one trial is limited at any size.
Sources
- US Food and Drug Administration. 21 CFR 862.1620, Progesterone test system. Electronic Code of Federal Regulations. https://www.ecfr.gov/current/title-21/section-862.1620
- US National Library of Medicine. Serum progesterone. MedlinePlus Medical Encyclopedia. Reviewed May 22, 2025. https://medlineplus.gov/ency/article/003714.htm
- Anckaert E, Jank A, Petzold J, et al. Extensive monitoring of the natural menstrual cycle using the serum biomarkers estradiol, luteinizing hormone and progesterone. Practical Laboratory Medicine. 2021. https://doi.org/10.1016/j.plabm.2021.e00211
- Schüring AN, Kelsch R, Pierściński G, Nofer JR. Establishing Reference Intervals for Sex Hormones on the Analytical Platforms Advia Centaur and Immulite 2000XP. Annals of Laboratory Medicine. 2016. https://doi.org/10.3343/alm.2016.36.1.55
- Practice Committee of the American Society for Reproductive Medicine. Fertility evaluation of infertile women: a committee opinion. Fertility and Sterility. 2026. https://doi.org/10.1016/j.fertnstert.2026.08.686
- Leiva R, Bouchard T, Boehringer H, et al. Random serum progesterone threshold to confirm ovulation. Steroids. 2015. https://doi.org/10.1016/j.steroids.2015.06.013
- Verhaegen J, Gallos ID, van Mello NM, et al. Accuracy of single progesterone test to predict early pregnancy outcome in women with pain or bleeding: meta-analysis of cohort studies. BMJ. 2012. https://doi.org/10.1136/bmj.e6077
- Coomarasamy A, Devall AJ, Cheed V, et al. A Randomized Trial of Progesterone in Women with Bleeding in Early Pregnancy. New England Journal of Medicine. 2019. https://doi.org/10.1056/nejmoa1813730
- Venetis CA, Kolibianakis EM, Bosdou JK, Tarlatzis BC. Progesterone elevation and probability of pregnancy after IVF: a systematic review and meta-analysis of over 60 000 cycles. Human Reproduction Update. 2013. https://doi.org/10.1093/humupd/dmt014
- Melo P, Chung Y, Pickering O, et al. Serum luteal phase progesterone in women undergoing frozen embryo transfer in assisted conception: a systematic review and meta-analysis. Fertility and Sterility. 2021. https://doi.org/10.1016/j.fertnstert.2021.07.002
- Filicori M, Butler JP, Crowley WF. Neuroendocrine regulation of the corpus luteum in the human. Evidence for pulsatile progesterone secretion. Journal of Clinical Investigation. 1984. https://doi.org/10.1172/jci111370
- Roper SM, Rubin JR, Ali M, et al. Accuracy of Two Progesterone Immunoassays for Monitoring In Vitro Fertilization. The Journal of Applied Laboratory Medicine. 2018. https://doi.org/10.1373/jalm.2017.024489
- Lawrenz B, Sibal J, Garrido N, et al. Inter-assay variation and reproducibility of progesterone measurements during ovarian stimulation for IVF. PLOS ONE. 2018. https://doi.org/10.1371/journal.pone.0206098