A 30-year-old male asked:
my nurse said opk can detect hcg in the system after the trigger. does this also mean opk can detect pregnancy on the day period is due.
1 doctor answer • 5 doctors weighed in
Fertility Medicine 20 years experience
Cross reaction: An OPK is meant to detect the hormone lh which surges at the time of ovulation. A urine pregnancy test is meant to detect hcg, the hormone of pregnancy. However, both HCG and lh are very close relatives chemically and that's why the OPK can pick up a pregnancy and the urine pregnancy test can pick up an ovulation surge. You should still use each test for its specific purpose.
5k viewsReviewed >2 years ago
Last updated Feb 13, 2015
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