Baby Nolan arrived Apr 18, 2009! asked:
My doctor wants to put me on a certain medication that has an unknown effect on a fetus. Since there is a good chance that I could be pregnant this month, she did a blood pregnancy test first to rule out a pregnancy- the results will be available tomorrow morning.
My period isn’t due until July 30th, which is an entire week away. Would a positive result show up this soon even in a blood test? How early was a positive blood test detectable for you?
I ovulated a week ago.


A blood test can detect pregnancy a week after conception. For most women, that would still be at least 1 week before they expected to start their period, so yes, your test results should be accurate. Good luck.
Blood tests can tell if you are pregnant about 7-12days after conception
6 weeks….after a missed period..HUGS!!
I did fertility treatment for two of my pregnancies. One week after insemination they would do a blood test to see if I ovulated and two weeks after that a blood test to see if I was pregnant. So yes, plenty of time should have elapsed in order to determine if your pregnant via a blood test. Your doctor wouldn’t have suggested it if she wasn’t sure about the timing (based on your recollection of your LMP), otherwise she would have suggested you wait another week to take the test.
Once fertilization has occurred and implantation has been achieved, the hormone hCG is released into the blood. The time limit for this can vary due to sensitivity of the test and the amount of this particular hormone that’s released. If memory serves me correctly, (been a while since I worked in OBGYN or L&D) the blood test could be accurate within 5 to 7 days after conception.
I’m sure your physician is testing for the levels of hCG in your blood as a means to r/o pregnancy. The blood test is used to detect the qualitive as well as the quantitive levels; this is an indicator to determine a pregnancy.