When trying to conceive, many women use ovulation predictor kits, or OPKs, to determine when ovulation is likely to occur. But do they work?
OPKs predict ovulation by detecting the surge of Luteinizing Hormone, or LH, that typically occurs just before ovulation. This means that in order to detect ovulation, a woman must test for LH for several days before she expects to ovulate. Depending on her typical cycle length will determine just what cycle day she should begin testing.
A typical, store bought, OPK contains five test strips and can be quite pricey, in the $15 range. Because price is a concern, it’s important for the woman to have a pretty good idea when to begin testing. The instructions that come with the ovulation predictor kit generally offer suggestions based on cycle length. For example, a woman with a 30 day menstrual cycle would begin using OPKs on cycle day 13 while a woman with a 36 day cycle would start using her OPK test strips on cycle day 19.
Using the ovulation predictor kits is as simple as peeing on a stick. In fact, many woman trying to conceive soon become obsessed with peeing on sticks or in cups as any trying to conceive message board can attest to. It’s recommended to test around 2:00 PM as most women experience the surge in the morning and it takes several hours for the LH to increase in the urine.
Once the woman begins using the OPK, she must interpret the results. Women always have LH in their systems so faint lines do not necessarily mean a positive result. What OPKs are designed to detect is the surge of LH. A positive result of an OPK is when the test line is as dark or darker than the reference line.
After several days of testing, a surge of LH may be detected. The OPK will show a line that’s as dark as the reference line or even darker. This is the moment of truth. Now the woman can expect to ovulate within 12-48 hours. Now she knows she should hit the sheets.
The problem with OPKs lies in their vagueness. The sticks are difficult to interpret with their varying degrees of faint lines making it difficult to detect a true positive result. And once a positive result is made, 12-48 hours is a long window of time. In addition, buying Ovulation Predictor Kits each month is a costly proposition.
To overcome some of these problems, chart basal body temperature as well as use OPKs on a few cycles. Instead of running down to the corner drugstore for an ovulation predictor kit, try the internet where OPKs can be found for around a dollar or less each versus up to $15 at the store.