Hello and hope you are doing well.
Ovulation kits are used to detect the exact day of ovulation or release of egg in a woman for infertility treatment .This test measures level of the leutinising hormone and Follicle Stimulating Hormone. LH levels are highest on ovulation day. The sperms remain alive in female body for 72 hours and so intercourse a day before or after too could help woman conceive. This test too like any other test has its own limitations and advantages. It is best to consult a doctor before using it and sonography is the most reliable tool to pick up the ovulation day. This is merely an advice. For more queries and assistance you are suggested to contact your gynecologist. I sincerely hope it helps.
Best wishes and regards!