What Serum Progesterone Blood Can Do For You

Women who have trouble getting pregnant often have plenty of questions about their condition, especially if they feel normal, or if they have no symptoms to report. They may schedule an appointment with their physician, who would perform a complete medical history and physical exam, only to discover unremarkable or otherwise normal findings. The next step is to run a few blood tests, which may be more suggestive of an underlying condition.

Despite many advances in assistive reproductive technology in the Philippines, there are fundamental diagnostic exams that must be performed prior to embarking on a course of action. One of these examinations is the serum progesterone test. As the name implies, this test measures the amount of progesterone in the serum, or blood. This is a test to measure general ovarian function.

Progesterone is a hormone that plays an important role for promoting and sustaining pregnancy. During a woman’s normal menstrual cycle, the ovaries release progesterone shortly after ovulation. The role of this hormone is to prepare the uterus for the implantation of an embryo, which in turn has developed from a fertilized egg. Additionally, progesterone functions to prepare the breasts for the production of milk.

Since the serum progesterone test requires a blood sample, the patient is instructed to discontinue the taking of any birth control pills or any progesterone supplements on the days leading up to the test. This is to ensure that the results of the test are not confounded by any variables. Blood is collected via venipuncture, which includes sterilization of the skin in preparation for the exam, as well as aseptic technique for blood extraction. Patients may feel a momentary prick or stinging sensation.

The assisted reproductive therapy physician may order the test for the following reasons:

  • To ascertain whether a woman is ovulating.
  • To evaluate the risk for miscarriage or ectopic pregnancy early in the pregnancy term.
  • To determine underlying causes for miscarriages in women with a low OB score.

The following is a table for women’s normal ranges of progesterone levels during different phases of the menstrual cycle, as well as during pregnancy:


< 1 ng/ml


5 to 20 ng/ml

1st Trimester Pregnancy

11.2-90.0 ng/ml

2nd Trimester Pregnancy

25.6-89.4 ng/ml

3rd Trimester Pregnancy

42.5-48.4 ng/ml


The reference values above may vary between different laboratories, or may use different units of measurement.

Results outside the normal range may be due to a variety of reasons. Abnormally high results may be due to pregnancy, adrenal carcinoma, ovarian cancer, or congenital adrenal hyperplasia. Results that are lower than normal may indicate amenorrhea, ectopic pregnancy, failure to ovulate, fetal death in utero, and miscarriage.

The serum progesterone test is a valuable tool that can be used to answer several questions about infertility, especially when used in conjunction with other diagnostic examinations, such as clinical findings and imaging techniques. Assisted reproductive therapy is highly dependent on such important diagnostic modalities available in the local setting.