A woman using ovulation predictor kits consistently gets positive results well into her luteal phase. Which mechanism most likely explains this outcome?

💡 Explanation

The kits detect luteinizing hormone (LH), and LH levels rise during the luteal phase due to corpus luteum support. Cross-reactivity occurs if other hormones mimic LH’s structure, triggering a false positive result, because the antibodies in the test are not fully specific; therefore, the kit inaccurately reports ovulation rather than other hormonal fluctuations.

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