Using Ovulation Tests (aka OPKs) for IUI

One of the easiest and most effective ways to track ovulation from home is by using an ovulation test or ovulation predictor kit (OPK). [1] Because fertility treatments are not often covered by insurance, OPKs are a low-cost option to help you and your physician determine the optimal timing for an IUI procedure. [1] 

By Dr. Liz Kane

IUI (intrauterine insemination) is a procedure in which concentrated sperm is placed into the uterine cavity at the time of ovulation. [2] It is usually a quick, safe, and painless procedure that involves placing a speculum to visualize the cervix, and then inserting a small catheter through the cervical canal into the upper uterus, where the sperm can swim into the fallopian tube and find the ovulated egg. [2] This procedure can be performed by a physician (fertility specialist or OBGYN) or a mid-level provider (ie. nurse practitioner or physician assistant). Learn more in The Scoop on IUI. 

IUI Timing Is Critical

Once a mature egg is released from the ovary, the egg must be fertilized within about 24 hours for pregnancy to occur. [3] To pinpoint this timing, your physician will either use ultrasound monitoring at the clinic or will have you use Ovulation Predictor Kits at home. [1-2] Monitoring at home through Ovulation Predictor Kits can save time and money and one study of 719 patients showed both methods had similar pregnancy rates. [4] 

You might be wondering—what time of day are you most likely to get your positive result? There isn’t an overall consensus yet, although one study found that people most often got their positive test results at lunchtime, between 11 am and 3 pm. [5] 

IUI Trigger Shot Timing

Your doctor can also precisely control when an egg is matured by using what is informally called a “trigger shot” that induces an egg to mature and ovulate within 24-36 hours. [6] The trigger shot is usually composed of human chorionic gonadotropin (hCG), which is structurally similar enough to luteinizing hormone (LH), the hormone that induces eggs to mature and ovulate, that your body reacts the same way hCG as it would to LH. [2,6] This option usually involves blood work and ultrasounds and can be more financially burdensome for those who are self-paying for fertility treatments. 

When To Do IUI After Positive Ovulation Test

If the procedure is using frozen sperm (say, from a donor), it is especially important to time the introduction of sperm as close as possible to ovulation. That is because sperm that has been frozen is estimated to live in a woman's body for at most 24 hours. [7] Because of this, some physicians recommend doing an insemination the day your OPK is first positive and again the following day to maximize the chances of sperm arriving in the vicinity of the egg when it is released. [2,3,7] 

How To Use Ovulation Predictor Kits

After you follow the test instructions, pee into the cup, place the cup on a flat surface, dip the test into the cup of urine for 20 seconds, and wait five minutes for results. Then take a look at the test window. To determine your result, you must compare the color intensity of the test line to the control line.

As your cycle progresses and you test daily (or twice daily), the darkness of the test line will increase; this indicates that your LH levels are increasing, and you are approaching your LH surge. When it is as dark or darker than the control line, you are experiencing your LH surge, and you will likely ovulate within 24-48 hours. Use the included cycle tracker to monitor LH progression.

You’ll want to be sure your test is 100% positive before you inseminate. If your test line is almost as dark as the reference line, but not quite, it is not yet a positive result. 

Check out The Ovulation Test Cheat Sheet. 

Natalist Ovulation Test Kit for IUI

When undergoing IUI and other fertility treatments, it’s important to have products you can trust. The Natalist Ovulation Test Kit is easy to use and reliable (over 99% accurate). Natalist also offers high-quality, plastic-neutral products like prenatal vitamins for women, women’s fertility test, and more. Have more questions about ovulation tests or fertility treatments? Learn more on the Natalist blog, or shop the Guide to IVF for a comprehensive overview of in vitro fertilization. 

References:

1. Yeh PT, Kennedy CE, Van der Poel S, Matsaseng T, Bernard L, Narasimhan M. Should home-based ovulation predictor kits be offered as an additional approach for fertility management for women and couples desiring pregnancy? A systematic review and meta-analysis. BMJ Glob Health. 2019;4(2):e001403. Published 2019 Apr 25. doi:10.1136/bmjgh-2019-001403
2. Allahbadia GN. Intrauterine Insemination: Fundamentals Revisited. J Obstet Gynaecol India. 2017;67(6):385-392. doi:10.1007/s13224-017-1060-x
3. Oliver R, Basit H. Embryology, Fertilization. [Updated 2023 Apr 17]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-
4. Storer, B. & Peck, J.D. & Craig, L. & Miller, T.. (2015). Are Intrauterine Insemination Pregnancy Rates Comparable between Ultrasound Monitoring and Home Ovulation Predictor Kits?. Fertility and Sterility. 103. e36. 10.1016/j.fertnstert.2014.12.069. 
5. Khattab AF, Mustafa FA, Taylor PJ. The use of urine LH detection kits to time intrauterine insemination with donor sperm. Hum Reprod. 2005;20(9):2542-2545. doi:10.1093/humrep/dei098
6. OVULATION INDUCTION. Northwestern Medicine. Accessed January 2024. https://fertility.nm.org/ovulation-induction.html
7. Fertility and Ovulation. Sperm Bank of California. Accessed January 2024. https://www.thespermbankofca.org/insemination-pregnancy/fertility-and-ovulation/

Originally published Feb 13, 2020. Updated for accuracy and relevancy on Jan 11, 2024. 

Dr. Elizabeth Kane is an entrepreneur, scientist, and board member with expertise in neuroscience, biology, and chemistry. Dr. Liz earned her Ph.D. in Biological and Biomedical Sciences from Harvard University and her BA in Biology from New York University. She currently serves on the Member Board of Trustees for the Cooper School and the Faculty Governing Board for the Museum of Comparative Zoology at Harvard University.