Ovulation Predictor Kits: What are they?


As promised, each Thursday, we will now offer you a piece of educational, science, or research related information.  The purpose of our #ThursdayThoughts post is to share with you fact-based content that can enlighten and assist you on your fertility journey.  Enjoy our post! Helping to Create New Beginnings….

Ovulation Predictor Kits: What are they?

In a normal menstrual cycle, estrogen levels in the blood reach a specific threshold, stimulating the hypothalamus and anterior pituitary gland and causing a surge of luteinizing hormone (LH). The start of this LH surge occurs 35-44 hours before ovulation. Peak LH occurs approximately 10-12 hours before ovulation.  1

Ovulation predictor kits (OPKs) are readily accessible kits you can purchase at the local pharmacy. These test strips work by detecting luteinizing hormone in the urine. Within the kit, there are several test strips that you would use just like a home pregnancy test. Using OPKs usually starts on days 10-11 of the menstrual cycle. Once you have a positive result, timed-intercourse is advised. To increase the chances of pregnancy, intercourse should occur 2 days prior to ovulation. If you are planning an intra-uterine insemination (IUI), then once you get a positive OPK result the IUI should be planned to occur within the following 24-48 hours. The U.S. National Academy of Clinical Biochemistry Laboratory Medicine practical guidelines reinforces that a positive result predicts ovulation within 48 hours. 1

Use of OPKs is relatively easy, non-invasive, and help predict when ovulation is going to occur. Sometimes OPKs can be difficult to read and costs can add up if you are buying kits for multiple months. This method typically does not work well for women with polycystic ovarian syndrome (PCOS). These women tend to have prolonged elevated LH level and may not reach a peak ovulation time. If you have questions or concerns, please discuss them with your provider during your next appointment. To inquire about fertility evaluation and treatment options, please contact Fertility Institute of Hawaii at 808-545-2800 and/or check out our web page https://www.ivfcenterhawaii.com/

Ovulation Predictor Kits


Su HW, Yi YC, Wei TY, Chang TC, Cheng CM. Detection of ovulation, a review of currently available methods. Bioeng Transl Med. 2017;2(3):238-246.

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