Progesterone
Code:9021|CPT:84144|LOINC:2839-9
| Includes | Progesterone |
|---|
Analysis details
Methodology
- Electrochemiluminescence immunoassay (ECLIA)
Expected Turnaround Time
1 day
Special Instructions
- Do not eat for 2–3 hours before specimen collection; drinking water is allowed.
- If clinically appropriate and authorized by the treating clinician, stop steroid and thyroid hormone medications 48 hours before testing.
- Avoid vigorous exercise and significant emotional stress for 24 hours prior to collection.
- Refrain from smoking for 3 hours before the blood draw.
- Screen for biotin use (vitamin B7/B8, vitamin H, coenzyme R) and discontinue it at least 72 hours before collection.
How to use
The Progesterone (P4) test, also known as pregn-4-ene-3,20-dione measurement, is used to verify corpus luteum activity, confirm the occurrence and timing of ovulation, and judge luteal phase adequacy during infertility assessment. It serves as a general indicator of ovarian function and is applied to track progesterone therapy in early gestation. In pregnancy, serum progesterone helps evaluate placental function and, when paired with quantitative hCG, contributes to the evaluation of suspected ectopic or nonviable pregnancy.
Limitations
Progesterone prepares the reproductive tract for possible conception. Estrogen drives cyclic endometrial proliferation, while the midcycle surge of luteinizing hormone initiates ovulation and corpus luteum formation; the corpus luteum then secretes progesterone. In concert with adrenal steroids, progesterone limits additional endometrial proliferation and conditions the uterus for implantation. If fertilization does not occur, the corpus luteum involutes, serum progesterone falls, and menstruation follows. If implantation occurs, corpus luteum secretion continues until placental steroidogenesis develops, after which the placenta becomes the primary source of progesterone during pregnancy.
| Unit | ng/mL | ||||
|---|---|---|---|---|---|
| Reference interval |
| ||||
| Indications | Assessment of ovulation, including cycle‑timed sampling within a menstrual cycle, Follow-up during pharmacologic ovulation induction, Workup of suspected ectopic pregnancy or threatened abortion, Surveillance of progesterone replacement or support during pregnancy, Evaluation of fetal–placental status in high‑risk pregnancy, Investigation of abnormal uterine bleeding in a nonpregnant individual |
Possible Causes of Abnormal Results
Increased levels
- biotin
Specimen Requirements
| Specimen | Serum |
|---|---|
| Container | Gold/Tiger Top (SST, Gel Separator) |
| Volume | 1 mL (min 0.7 mL) |
| Storage Instructions | Room temperature, Refrigerated, Frozen |
References
Hilborn S, Krahn J. Effect of time of exposure of serum to gel-barrier tubes on results for progesterone and some other endocrine tests. Clin Chem. 1987 Jan;33(1):203-204. PubMed 3802491
Nippoldt TB, Reame NE, Kelch RP, Marshall JC. The roles of estradiol and progesterone in decreasing luteinizing hormone pulse frequency in the luteal phase of the menstrual cycle. J Clin Endocrinol Metab. 1989 Jul;69(1):67-76. PubMed 2499593
Rebar RW. The ovaries. In: Wyngaarden JB, Smith LH Jr, eds. Cecil Textbook of Medicine. 18th ed. Vol 2. Philadelphia, PA: WB Saunders Co; 1988:1425-1446.
Romero R, Scoccia B, Mazor M, Wu YK, Benveniste R. Evidence for a local change in the progesterone/estrogen ratio in human parturition at term. Am J Obstet Gynecol. 1988 Sep;159(3):657-660. PubMed 2971319
Stewart MO, Whittaker PG, Persson B, Hanson U, Lind T. A longitudinal study of circulating progesterone, oestradiol, hCG and hPL during pregnancy in type 1 diabetic mothers. Br J Obstet Gynaecol. 1989 Apr;96(4):415-423. PubMed 2751954