Ovulation tests or Ovulation predictor kits (sometimes called “OPK’s” for short) are a relatively accurate tool when it comes to detecting ovulation. By measuring the levels of Luteinizing Hormone (LH) in a woman’s system, an ovulation test can help her to know when she is having her LH surge. The LH surge occurs between 12 and 48 hours prior to the time that she ovulates, with it typically occurring right around 36 hours prior to ovulation.
There are some things, however, that can cause a problem with the levels of luteinizing hormone in a woman’s body, and therefore interfere with the accuracy of an ovulation test. For example, a woman with Polycystic Ovarian Syndrome, or PCOS, can sometimes have an unusually high level of luteinizing hormone. Most of the time, these increased levels of luteinizing hormone are not enough to trigger a positive result on an ovulation test, but it has been known to happen in some cases.
The fertility medication Clomid can also cause higher levels of LH. This is because Clomid works to help with fertility by reacting with all of the tissues in the body that have estrogen receptors, such as the hypothalamus, pituitary, ovary, endometrium, vagina, and cervix. Clomid influences the way that the four hormones required for ovulation, GnRH, FSH, LH and estradiol, relate and interrelate. While we do not completely understand the mechanisms by which this drug works, in essence it appears that Clomid fools the body into believing that the estrogen level is low. This altered feedback information causes the hypothalamus (an area of the brain) to make and release more gonadotropin releasing hormone (GnRH) which in turn causes the pituitary to make and release more FSH and LH. Thus, in some cases, a woman that is taking Clomid may have higher levels of LH that could cause a false positive result on an ovulation test. Having said that, this is relatively uncommon, as well.
With these rare exceptions, ovulation tests typically do an extremely accurate job at detecting ovulation.
This entry was posted
in Getting Pregnant.