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Ovulation prediction test kits (OPK) are available at leading over the counter. These kits detect LH, which is produced in large quantities shortly before ovulation and can be found in the urine. Once the LH surge has occurred, ovulation usually takes place within 12 to 44 hours. Urine testing is started about two days prior to the expected day of ovulation and continues until the test becomes positive. The urine should be collected at the same time every day - and testing the first morning urine sample is a good idea.
If your menstrual cycles are irregular, testing should be timed according to the earliest and latest possible dates of ovulation. For example, if your cycle ranges between 27 and 34 days, you could possibly ovulate between days 13 and 20. Therefore, testing should begin on day 11 and continue until ovulation is indicated or through day 20. There is an 80 percent chance of detecting ovulation with five days of testing and a 95% chance with ten days of testing. Occasionally, ovulation may not occur in a particular cycle. If the ovulation prediction test has been timed and performed accurately and has not turned positive, you should discontinue testing and begin again with your next menstrual cycle. Persistent failure of the test to turn positive may indicate a problem with regard to ovulation.
Once a test has registered positive, indicating that ovulation is about to take place, it is no longer necessary to continue testing. Remaining tests in a kit may be saved and used in the following menstrual cycle if pregnancy does not occur.
Ovulation prediction kits offer the advantage that they allow you to predict when ovulation will occur - thus maximizing the chances that intercourse will be timed at your most fertile period. They can also be done in the privacy of your own home. However, they are expensive; and some of the kits have very tedious and involved testing procedures, so that errors are not uncommon.
A newer device, The ClearPlan EasyTM Fertility Monitor is a palm-sized, electronic system, that provides information about fertility status by interpreting the levels of two hormones, estrogen and luteinizing hormone, in the urine. You need to test your urine for the presence of these, using dipsticks, and the information is then input into the system, which uses it to calculate your fertile days.
Another way of monitoring ovulation is by using a pocket microscope to check for the phenomenon of "saliva ferning." You need to let your salivary dry on a glass slide, and then examine it under the device, to check for ferning. Prior to ovulation, the saliva shows the presence of crystallization or ferning when it dries, and this suggests that ovulation will occur soon. Though these devices are now commercially available, their reliability is still unclear.
The maturing follicle secretes the hormone estradiol in increasing amounts and its blood level rises rapidly several days prior to ovulation. If ovulation is being induced through fertility drugs, estradiol blood tests may be done on a daily basis in order to determine if the developing follicles are growing properly. Normally, the estradiol blood levels should increase rapidly (as a rule of thumb, they double every 24 hours). Each mature follicle produces about 200-300 pglml of estradiol.
Since the luteinizing hormone (LH) blood level rises rapidly just before ovulation (this is called the LH surge), frequent blood samples for measuring the LH level can also be taken a few days prior to the anticipated time of ovulation in an attempt to predict when the follicle is mature and ready for ovulation.
© Dr. Aniruddha Malpani and Dr. Anjali Malpani www.drmalpani.com
Credits: How to Have a Baby: Overcoming Infertility
