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DrRussMD
DrRussMD, Board Certified Physician
Category: OB GYN
Satisfied Customers: 65296
Experience:  Internal Medicine--practice all of internal medicine, all ages, family, health, prevention, complementary medicine, etc.
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Can you get a false negative home pregnancy test 30 days

Customer Question

Can you get a false negative home pregnancy test 30 days after sex?
Submitted: 2 months ago.
Category: OB GYN
Expert:  DrRussMD replied 2 months ago.

Hi.
Welcome to just answer. I am here to answer questions for education and information. I will respond shortly with an answer, or a question for you

Expert:  DrRussMD replied 2 months ago.

Is it s new pregnancy test

When is your period due?

Customer: replied 2 months ago.
it is a new pregnancy test from walmart. I took plan b immediately after sex and got my period 3 days later.
Expert:  DrRussMD replied 2 months ago.

OK

Those tests are accurate.

It is likely that plan B threw off your cycle, which can happen.

Talk to your doctor, and if you are very concerned, a blood test for pregnancy is full proof, but I doubt you are pregnant.

You can also repeat the home test if you are due. No way you are going to get two false negatives if you are doing it correctly.

Let me know if you have more questions.

Also, please click a positive rating on the rating scale. In fact, a 5 rating squares me with just answer and allows me to provide prompt and accurate service to you, but does not increase your cost. And, I will be here for any follow up needed.

Customer: replied 2 months ago.
Would you say that I am 100% not pregnant? I also tested at day 14 and 22 after sex
Expert:  DrRussMD replied 2 months ago.

99.99%.

Nothing is EVER 100%

A blood test is as close as you get.

But the new tests are accurate at 30 days.

I did not run the test however, so there is always human error, but I doubt that is the case here.

However, if you miss a period, you still need to see your doctor, as plan B can through hormones off a lot in some women, and you need your doctor to be telling you that all is OK, we do not replace your doctor visit.

But I would bet it is fine.

good luck.

Please do this manually at the top of the page: a 5 rating squares me with just answer and allows me to provide prompt and accurate service to you, but does not increase your cost. And, I will be here for any follow up needed.

Customer: replied 2 months ago.
Ok thanks. What is the possible human error? I dipped it in a cup
Expert:  DrRussMD replied 2 months ago.

On this test, not really any.

Please click a 5 rating.

You have to do it, I can't.

I think it will be fine.

Good luck.

Find me by request as needed.