Does a pregnancy test come +ve results at 8 days post-ovulation (8 DPO) happen often? A positive pregnancy test at 8 days post-ovulation is possible if the fertilized egg implants as early as 6 days post-ovulation. This condition is extremely rare, affecting less than 0.5% of women. Early pregnancy test takers are more likely to have miscalculated their ovulation date.
https://www.mybump2baby.com/8-dpo-pregnancy-symptoms/