Turnaround times
The quoted turnaround time is from sample receipt in the laboratory, to results authorisation in the Laboratory Information Management system. The times do not include transport of specimen to the laboratory or the administrative process to print and post/email reports. Service users must allow for transport and reporting time when ordering tests.
Clinical background:
Progesterone is a steroid hormone synthesized from pregnenolone. It is a key intermediate for the synthesis of the other adrenal corticosteroids and sex hormones. Progesterone is secreted by the ovaries and placenta, with the adrenal cortex and testes being minor sources. The major function of progesterone is the regulation of the menstrual cycle in women. During the follicular phase, low concentrations of progesterone are found in serum. After ovulation, during the luteal phase, the progesterone concentration rises sharply for 5 to 10 days due to secretion by the corpus luteum. If implantation of a fertilized ovum does not occur, a steep decline of progesterone to baseline levels is seen at about 4 days prior to menses.
Progesterone is also responsible for the maintenance of pregnancy. It induces the glandular morphology of the uterine endometrium to allow implantation of the fertilized ovum. Progesterone is secreted by the corpus luteum during the first trimester and by the placenta during later stages of pregnancy to support development of the foetus. Decreased progesterone levels, during the luteal phase or the first trimester of pregnancy, often reflects luteal insufficiency which may result in a low success rate of implantation or spontaneous abortion. During the later phase of pregnancy, progesterone is believed to suppress uterine muscular contractions until just prior to parturition. It also prepares the breasts for lactation by stimulating growth of the mammary glands.
Determination of progesterone concentration in serum is routinely used in assessment of sexual development, aetiology of amenorrhea and causes of infertility. It is used clinically to confirm ovulation and normal function of the corpus luteum in non-pregnant woman.
Specimen container paediatric:
Serum (SST or plain tube)
Specimen container adult:
Serum (SST or plain tube)
Minimum volume paediatric:
0.5 mL blood
Minimum volume adult:
1 mL blood
Sample stability:
Unseparated sample:
7 days at 15-25C
Separated:
1 day at 15-25C
7 days at 4-8°C
1 year at -20°C
Transport requirements:
Ambient
Reference ranges:
Adults female:
< 5 nmol/L suggests anovulation
>25 nmol/L suggests ovulation
Results between 5 and 25 do not exclude ovulation
Other info:
Lithium heparin plasma samples also acceptable