Assessment of Ovulation

There are a variety of ways to determine whether a woman is ovulating. If a woman has regular menstrual cycles which are preceded by some premenstrual symptoms including breast tenderness or bloating, it is quite likely that she is ovulating. There are several means by which one can be certain that a woman is ovulating and these are tests that are frequently recommended in our program.

Basal Body Temperature Graph

A woman's basal temperature elevates by approximately 1 degree when comparing the early preovulatory phase with the postovulatory phase of the cycle. We recommend that you take your temperature the first thing each morning and record it on a graph which will be provided. When plotting this graph, if you are ovulating, you should see a rise in the temperature in the second half of the cycle compared to the first. The most fertile time for intercourse is just prior to the rise in the temperature seen in the second half of the cycle.

Basal Body Temperature Chart (pdf)

Serum Progesterone Levels

Progesterone is only secreted if a woman ovulates. We sometimes will recommend a serum progesterone level to document ovulation. This is best obtained around day 21 of the cycle when the progesterone level should be elevated. A progesterone level above 3 ng/ml indicates ovulation. We prefer to see the progesterone level around 10 ng/ml which would indicate that the amount of progesterone produced is adequate for implantation and pregnancy.

Ultrasound

By ultrasound, a developing follicle can be viewed and if followed over time the collapse of that follicle can be documented which indicates that ovulation has taken place. This is a rather expensive means of detecting ovulation and is seldom recommended. Under rare circumstance however, we do recommend this test.

Endometrial Biopsy

The endometrium undergoes characteristic changes following ovulation and those can be demonstrated by obtaining a biopsy of the endometrium and looking at the tissue under the microscope. This test is seldom performed in our unit as there are simpler and less expensive and less painful ways of documenting ovulation.