Would a pregnancy test be accurate after one week of possible conception?

Usually not: An embryo usually will not implant into the uterine lining until after 7 to 9 days from fertilization. Only after implantation will the beta HCG hormone be produced. The pregnancy over-the-counter test detects the beta HCG hormone.

Unlikely: Conception occurs within day or so of the sex. It takes about 3 weeks for the embryo to make enough HCG for a positive pregnancy test. Blood test may be done a day after a missed period. Home pregnancy tests should be done 4-5 days after the missed period. If the result is negative repeat the test in 4-5 days. Use first morning urine and follow instructions for the test carefully.