Progesterone

Clinical Significance:
Progesterone is a Progestin produced primarily from enzymatic metabolism of Pregnenolone.  It is enzymatically converted to 17-Hydroxy Progestrone and 11-Deoxycorticosterone.  It is secreted by both the gonads and the adrenal glands.  It is bound to Cortisol Binding Globulin and Albumin, but a small percentage is present in the “Free” bioactive form.  It is excreted into the urine as its conjugated and unconjugated forms and as Pregnanediol (conjugated and unconjugated).  Progesterone is responsible for cellular changes in the cervix, vagina, and uterus.  Levels are lowest in the follicular phase and increase rapidly following the luteal surge.  Increased Progesterone inhibits ovulation.  Progesterone increases greatly during pregnancy.  Measurement of Progesterone can be useful to monitor fertility, corpus luteum function, endometrial development, and be helpful in in-vitro fertilization patients.

Reference Interval:
Male:                                 10 – 100 ng/dl
Female:
  Follicular:                       10 – 100 ng/dl
  Luteal:                          200 – 1800 ng/dl

Procedure:
Progesterone is measured by radioimmunoassay.

Patient Preparation:
Patient should not be on any Corticosteroid, ACTH, Estrogen, or Gonadotropin medication, if possible, for at least 48 hours prior to collection of specimen.

Specimen Collection:
3 ml serum or EDTA plasma should be collected and separated as soon as possible.  Minimum specimen size is 1 ml.

Special Specimens:
For tumor/tissue and various fluids (i.e. CSF, peritoneal, synovial, etc.) contact the Institute for requirements and special handling.

Shipping Instructions:
Ship specimens frozen in dry ice.

References:
1. MS Gelder, LR Boots,and JB Younger.  Use of a Single Random Progesterone Value as a Diagnostic Aid for Ectopic Pregnancy.  Fertility and Sterility 55: 497-500, 1991.

2. CJ Munro, GH Stabenfeldt, JR Cragun, LA Addiego, JW Overstreet, and BL Lasley.  Relationship of Serum Estradiol and Progesterone Concentrations to the Excretion Profiles of Their Major Urinary Metabolites as Measured by Enzyme Immunoassay and Radioimmunoassay.  Clinical Chemistry 37: 38-44, 1991.