Lesson 1: Suspecting and Diagnosing Infertility
Fertility Charting VS. OPKs

If you have been trying to get pregnant for more than 12 months, most likely you have heard of both charting and ovulation prediction kits, or OPKs for short. You may have even used OPKs before, or may be considering using them now. However, before you spend the money you should know how they work and what the difference is between OPKs and charting.

Let's look at OPKs first, as they are easier to explain and understand. First, an OPK measures the lutenizing hormone in a woman's urine. This hormone, LH for short, is released by the pituitary, and surges about 24 to 48 hours before ovulation takes place. Approximately 6 hours after the LH surge is released, it will show up in a woman's urine and is usually detectable by a home test.

This surge of LH will last anywhere from 10 to 30 hours, so the timing of the test is important. For an OPK to be as effective as possible, a woman needs to test twice a day, first between 6 am and 10 am and again in the evening between 5 pm and 8 pm. A woman must also know on which days of her cycle to test. The 'rule of thumb' as to when to start testing is this: the first day of testing should be 18 days before your next period is due.

For a woman that 'always' has a 28-day cycle, the first day of testing should be day 10, or the 10th day of her new cycle. Testing should be continued until a positive result is seen. A woman with a 28-day cycle should expect to use between 8 and 20 test strips per month. With the average cost of an OPK $28, and the average OPK containing only 8 to 9 tests, you can see the expense involved in using OPKs.

So, what is charting and how does it differ from OPKs? Charting is something that a woman does every day of her cycle and consists of her basal body temperature (BBT), her cervical mucus or fluid (CM or CF), and her cervical position (CP). Other things can be recorded on the chart including: bleeding, spotting, cramps, headaches, food cravings, ovulation pain, medications, and intercourse. All of these things, when looked at together, can tell a woman several different things about her body and her fertility.

If a woman does not know how to chart her fertility signs, she can easily learn with the book "Taking Charge Of Your Fertility" written by Toni Weschler. Besides the book, the only other items needed to chart are a basal body thermometer and copies of charts, which are available in the book. The total cost of learning to chart with the book, and actually charting for 6 months is about $35 to $40.

So, you can already see the price difference between OPKs and charting, but what are some of the other differences?

In my book, charting wins hands down over OPKs, however, for the new charter, the use of OPKs as a 'back-up' to confirm that ovulation is being predicted at the same time by both methods can be helpful.