Fertility Blog

Home Monitoring of Ovulation

The marketplace offers a dizzying selection of devices to help women predict ovulation to increase their odds of conceiving. Collectively, these products are called ovulation predictor kits (OPKs) or fertility monitoring devices. They are broadly grouped into two main types: those that gauge a woman's Luteinizing hormone (LH) surge and those that monitor one's estrogen level. The LH surge is tracked with urine testing strips, which are then discarded. Estrogen can be tracked with longer-use fertility monitoring devices that check saliva or other bodily fluids. When under-going artificial insemination (AI) and intrauterine insemination (IUI), women need a very precise measurement of ovulation. Single-use OPKs that require urine testing first thing in the morning or after 2-4 hours of "holding it" are ideal for this. They react when a woman's pituitary gland sends out an LH surge, directing the egg to leave the ovary in 24-36 hours, like clockwork. The egg then spends the next 6-12 hours sliding down the fallopian tube where it must be fertilized before implanting into the uterus. This critical window requires sperm to be on the spot, ready to fertilize. For LH testing, PFC recommends ClearPlan/ClearBlue Easy and Ovu-Kit One-Step because, in our experience, they tend to give the most unambiguous results. The kits that are not as highly recommended are Answer, First Response and generics; they appear to be more prone to false negative results. For couples timing pregnancy to the LH surge, natural intercourse is recommended both on the day that the kit changes, and the next day. If a couple is going through IUI with fresh sperm, the insemination will be timed the day after the kit shows ovulation. If frozen sperm is being used, many times two inseminations take place: one on the day of change and another the following day. The longer-use ovulation monitors that use saliva to measure estrogen levels typically identify a 72 hour peak "zone" of fertility. Tracking estrogen levels can be a fascinating process, although patients may need additional time to train their eye to spot the critical pattern that appears in saliva with elevated estrogen. Curiously, the salt content in body fluids increases with a rise in estrogen. Once dried in a magnified setting, the saliva reveals a distinct crystallization, or "ferning" from the salt level (see illustration on left), similar to ice patterns on a frosty window. Some name brands include Fertile Focus, the Donna and Lady-Q. These devices are useful if couples can have frequent intercourse during their 3-6 day zone of fertility. A brand new product that also tracks ovulation via estrogen levels uses a wrist watch-like calculator that must be worn every night. This device makes direct contact with one's skin, and uses a sensor that contains a non-allergenic gel released to detect one's estrogen from the moisture released off the wrist. Since PFC has not reviewed the estrogen-monitoring products and their efficacy, patients are strongly advised to do their own research. *Reproduced with permission: www.maybeit.com