Description
Progesterone is a steroid hormone that helps prepare a woman’s body for pregnancy.
Progesterone stops endometrial growth and readies the uterus for the possible implantation of a fertilized egg.
If fertilization does not occur, progesterone levels drop, and menstrual bleeding begins. If a fertilized egg is implanted in the uterus, the corpus luteum continues to produce progesterone. After several weeks, the placenta replaces the corpus luteum as the main source of progesterone, creating relatively large amounts of the hormone throughout the rest of a normal pregnancy.
This test is used to help recognize and manage some causes of infertility. Progesterone can be measured to determine whether or not a woman has ovulated, to determine when ovulation occurred, and to monitor the success of induced ovulation.
Also, progesterone measurements may be used, along with human chorionic gonadotropin (hCG) testing, to help diagnose an ectopic or failing pregnancy. Progesterone levels also may be measured to monitor placenta and fetal health.
These progesterone levels may be monitored in women who have trouble maintaining a pregnancy, as low levels of the hormone can lead to miscarriage. If a woman is receiving progesterone injections to help support her early pregnancy, her progesterone levels may be monitored on a regular basis to help determine the effectiveness of that treatment.
Progesterone levels may be used, along with other tests, to help determine the cause of abnormal uterine bleeding.
Its concentration is measured by means of analysis of a blood sample drawn from the vein in the arm.
Purpose of the test
Progeterone levels in the blood help determine the cause of infertility, track ovulation, help diagnose an ectopic or failing pregnancy, monitor the health of a pregnancy, and help diagnose the cause of abnormal uterine bleeding.
It can be presecribed at specific times during a woman’s menstrual cycle to determine whether/when the woman is ovulating; during early pregnancy if symptoms suggest an ectopic or failing pregnancy; throughout pregnancy to help determine placenta and fetal health; and in cases of abnormal uterine bleeding.
Reference range values
ng/mL (SI: nmol/L = 3.18 x ng/mL)
Males >=16Y 0.27 – 0.9
Females:
Follicular 0.33 – 1.20
Luteal 0.72 – 17.8
Postmenopausal <0.2 – 1
Oral Contraceptives 0.34 – 0.92
Males & Females:
Cord 350 – 750
1D-3M 0.25 – 17
4M-12M <0.2 – 2
1Y-9Y <0.2 – 1.3
Abnormal findings
Low leves during an early pregnancy can mean ectopic pregnancy.
High levels of progesterone can mean more than one fetus (twins, triplets, etc.).
High progesterone levels also are seen occasionally with luteal ovarian cysts, molar pregnancies, and with a rare form of ovarian cancer.