Progesterone Blood Testing
Progesterone is a steroid hormone produced by both males and females and necessary for sexual health and reproduction. Although it is often referred to as a “female hormone” because of its predominant role in ovulation and pregnancy, men require it too, (albeit in smaller amounts).
In women, progesterone is produced mainly in the ovaries, and the placenta (if pregnant). Small amounts are also produced in the adrenal glands. In men, progesterone is produced in the adrenal glands and in the testes. Progesterone blood testing, also referred to as “progesterone, serum” testing may be ordered for either sex, to help monitor hormone levels for pregnancy, or to diagnose a medical condition or concern. Certain medications such as, oral contraceptives, or progesterone, ampicillin and clomiphene may affect test results. Radioactive tracer used in thyroid and bone scan tests within 7 days of blood draw may also skew results. Some progesterone testing must be done on specific days within a woman’s menstrual cycle.
Why Test Is Used
A progesterone test may be used to detect or monitor a number of medical conditions including:
- Progesterone treatment during pregnancy
- High-risk pregnancy
(High progesterone levels)
- Ovarian cysts
- Molar pregnancies
- Ovarian cancer
- Adrenal cancer
- Congenital adrenal hyperplasia (CAH)
(Low progesterone levels)
- Toxemia (in later stages of pregnancy)
- Decrease in ovarian function
- Absence of menstruation (amenorrhea)
- Ectopic pregnancy
- Abnormal uterine bleeding (non-pregnant women)
Progesterone testing may be used to detect low levels of the hormone in
males who may experience:
- Decreased libido
- Loss of hair
- Weight gain
- Gynecomastia (male breasts)
- Erectile dysfunction
Low levels of progesterone are associated with a higher risk of arthritis, osteoporosis, prostatism (difficulties with urination as a result of obstruction), and prostate cancer.
How does it work?
A progesterone test, or progesterone, serum test measures progesterone levels in the blood. In men, progesterone is a necessary precursor to testosterone and “preserver of masculinity.” Produced mainly in the testes, progesterone levels decline with age, along with testosterone. In addition to progesterone testing, men may have estrogen, cortisol, DHEA and thyroid hormone tests performed as well. In reproduction, progesterone signals the female uterus to prepare for implantation of a fertilized egg. As the fetus grows, the placenta also provides high levels of the hormone to support the pregnancy.
During pregnancy progesterone prevents the production of milk. The sharp decline at labor then triggers the body to start producing. Progesterone levels rise and fall with a woman’s menstrual cycle so timing is very important for monitoring some medical conditions or situations. An FSH (follicle-stimulating hormone), LH (luteinizing hormone), hCG (human chorionic gonadotropin), estrogen or thyroid test may be performed along with the progesterone, serum test for women.
Results for progesterone testing are reported in nanograms per milliliter and may vary by laboratory.
Normal ranges are as follows:
- Women before ovulation, postmenopausal women, and men: less than 1 ng/mL
- Women mid-cycle: 5 to 20 ng/mL
- Pregnant Women
1st trimester: 11.2 to 90 ng/mL
2nd trimester: 25.6 to 89.4 ng/mL
3rd trimester: 48.4 to 42.5 ng/mL
Ranges above or below normal could indicate one of the medical conditions listed above.