What is an Ovulation Predictor?

An ovulation predictor is a tool that hopeful couples use to predict when a woman will ovulate and when she should try to become pregnant. The ovulation predictor looks very much like a home pregnancy test. It is a plastic stick with a urine collector at one end and a result window on the other. Its function is to detect a surge in luteinizing hormone (LH), which signals the ovary to release an egg, resulting in ovulation. It is at this time in a woman’s cycle that she is able to conceive.

Before the advent of user-friendly, over-the-counter ovulation predictors, women had to chart their temperature and cervical mucous texture on a basal body temperature (BBT) and cervical mucous chart daily. This can be a tedious, involved process that must be done for several months in a row in order to accurately chart a woman’s cycle. An ovulation predictor gives a woman advance warning of ovulation the first time it is used. It can predict ovulation as early as six hours in advance.

Begin using the ovulation predictor kit from the middle of your cycle. The day that you begin testing is dependent upon the length of your cycle. If your cycle varies within a week or so, you may have to use up to ten tests per cycle. Since an ovulation predictor kit includes five to nine tests, at a price ranging from 15 to 70 US dollars (USD), it can become pricey quickly. The odds are good, however, and a woman using ten tests per cycle has about a 90% chance of detecting ovulation that cycle.

Once you select an ovulation predictor kit from the drugstore or online, use the instructions to determine which day to start testing. Unlike a pregnancy test, the first urine of the morning is not recommended for use with an ovulation predictor. Mid-day is the best time to test, but be sure to test at the same time every day.

One of the biggest complaints about ovulation predictors is that the results are often difficult to interpret. The result window usually has one dark pink line, which is the control line. The result line should be as dark or darker than the control line when signaling a surge in LH. Many women have a hard time determining which line is darker.

Others complain that there is always a faint pink result line, or that the result line darkens over time. All women have a small amount of LH in their system throughout their entire cycle, so it may register on the result line. A darkening result line may be an early signal of an LH surge.

A newer test by Clearblue has a digital readout, which indicates ovulation with a happy face. This takes the guesswork out of comparing lines on other ovulation predictors. The company claims that their ovulation predictor is 99% accurate.

Once an ovulation predictor gives a positive result, ovulation usually occurs within 12 to 48 hours. Intercourse is recommended for the day of the surge and for two to three days after. The rest is up to the egg and the sperm.

Although ovulation predictors are very useful tools in the quest for pregnancy, there are a few drawbacks. They are much more expensive than the lower tech BBT charts, and they don’t monitor the cervical mucous texture, which is a very important factor in conception. You must follow the directions exactly, and if you have irregular cycles, it may be difficult to know the best day to start testing. Fertility drugs can interfere with the test results as well. After all the testing, it is not guaranteed that you will ovulate, even if the ovulation predictor detects a surge in LH level.