Question:
can you get a false posotive pregnancy test?
2007-07-30 04:39:16 UTC
i did a test and it came up positive but the next day i did one with mu boyfriend and it came up negative i dont no what to think should i leave it a few weeks and see what the next one says i have not long jus misscarried so i dont know what to think please can you give me some advice thank :)
28 answers:
2007-08-06 09:03:06 UTC
You might have got a positive result from just recently having a miscarriage, or it could be that the negative test was wrong. So your best bet is to get a blood test by your doctor and find out for sure.
Cortney R
2007-08-04 19:09:34 UTC
There could be various reasons for a false positive test.



Chemical Pregnancy

A chemical pregnancy is basically an early miscarriage. Research has shown that half of all first pregnancies end in miscarriage. Due to the high sensitivity of home pregnancy tests, many women catch early pregnancies but end up going on to have their periods due to a chemical pregnancy.



Missed Reaction Time

For accuracy in home pregnancy tests it is essential that you read the test results in the stipulated reaction time. If you let the test sit for too long (after the instructions on the box tell you), the test is invalid. This may cause it to show false positive results.



Chemical Interference

Drugs that have the pregnancy hormone Human Chorionic Gonadotropin (hCG) in them can cause incorrect results in home pregnancy tests. The Human Chorionic Gonadotropin (hCG) in them may be responsible for the false positive pregnancy test. If you have had an HCG shot due to infertilty treatments, you need to be sure the shot is out of your system before you attempt to use early pregnancy tests.



Evaporation Lines

While technically not a true pregnancy, some pregnancy tests leave a faint evaporation line as the urine crosses the test. This faint very light grey evaporation line in the test area is often interpretted as a positive result.



AimStick pregnancy test strips have a very good reputation of NOT leaving evaporation lines and are much less expensive than brands you can buy in your local supermarket or drug store.
not2posh
2007-07-30 04:47:08 UTC
False positive pregnancy tests are rare - though there are instances and conditions where they can occur.



Chemical Pregnancy

A chemical pregnancy is basically an early miscarriage. Research has shown that half of all first pregnancies end in miscarriage. Due to the high sensitivity of home pregnancy tests, many women catch early pregnancies but end up going on to have their periods due to a chemical pregnancy.

Missed Reaction Time

For accuracy in home pregnancy tests it is essential that you read the test results in the stipulated reaction time. If you let the test sit for too long (after the instructions on the box tell you), the test is invalid. This may cause it to show false positive results.



Chemical Interference

Drugs that have the pregnancy hormone Human Chorionic Gonadotropin (hCG) in them can cause incorrect results in home pregnancy tests. The Human Chorionic Gonadotropin (hCG) in them may be responsible for the false positive pregnancy test. If you have had an HCG shot due to infertilty treatments, you need to be sure the shot is out of your system before you attempt to use early pregnancy tests.



Evaporation Lines

While technically not a true pregnancy, some pregnancy tests leave a faint evaporation line as the urine crosses the test. This faint very light grey evaporation line in the test area is often interpretted as a positive result.

AimStick pregnancy test strips have a very good reputation of NOT leaving evaporation lines and are much less expensive than brands you can buy in your local supermarket or drug store.



If you are not sure about your home pregnancy results it is recommended that you try again after a couple of days. If doubts regarding the results still persist, you must see a doctor for a pregnancy blood test. A blood test administered by your doctor is more sensitive than the early home tests and can be taken between seven and twelve days after you conceive.
Cindy; mum to 3 monkeys!
2007-07-30 04:50:35 UTC
False positive isn't very common as a certain hormone is detected that otherwise wouldn't normally be there. False negative is more common. If it says positive it usually is. However if you have recently miscarried than you may be showing different results. I would wait another couple of days and then test again. If you still haven't got a period and the test is still negative than see your doc for a blood test and exam. This is the most accurate test.



Good luck and fingers crossed. You may just be too early for a test to accurately detect it.
2007-08-06 12:20:55 UTC
Did you have a different brand of tests that you used?



and also did you test before your period?



If yes, you may have tested to early. Each brand normally measures different amount of hormone.



I read on the internet that you can't false positives. Which makes sense.



Make sure that you do another test, with the same brand you got a positive with and then see the results that you get, in the mean time make an appointment with your GP (you have to when pregnant anyway). Do the test in the morning, because you'll have a longer hormone build up.



Good luck, and let us know how you get on x
2007-07-30 04:54:50 UTC
hello pregnancy tests rarely give a false pos as a hormone called hcg (pregnancy hormone) must be detected in your urine thus proving the pos result. however false neg are common due to being early pregnant and depending on what time u test first morning sample is genuinely the best. the reason is because the hcg hormone in early pregnancy is low and not all tests can pick it up. my guess is u are in fact pregnant congratrs girl. go to ur doc they can give u a blood test and let you no for sure take care lol. its not uncommon for a woman to concieve soon after miscaridge or birth of a child as this is a time when ur most fertile. however if this is a false alarm i would advise waiting three mths b4 trying again just to let your body recover as its a big amount of stress your body has to go through and u want to allow it time to recover.. but good luck girl, xxxxxx
2007-08-06 12:36:29 UTC
When i was pregnant, i did the test on my own and it was positive. Then I told my boyfriend who got excited so I took another to make sure..and it was negative, so were the next three I took. So I went to the doctor the next day and he told me i was pregnant. The other tests had came up negative because I had drank lots of water, diluting my urine. The best thing to do is go to the doctor, they'll be more accurate...and i would be too excited to wait for a week!!
charli
2007-07-30 04:51:25 UTC
it is highly unlikely for you to get a false positive pregnancy test result...ony in circumstances where you would have lost a baby...but you would know if you had. Sorry, just read the bit at the end, sorry for your loss.

Maybe you just had pregnancy hormones in your body still? But false negatives are more common so yes i would do another test in a couple of weeks, or go and speak to your gp. Good luck hun, and I hope everything works out for you.
mumontherun
2007-08-05 04:40:38 UTC
It would be best to go and get the doctor to do a blood test. If you miscarried then the test the day after would still say you are pregnant because it takes a few weeks for your bodies hormones to return to normal - so your pregnancy test would've still been positive if you miscarried. There is room for error in the preg tests, but the doctors one is fairly reliable.
2007-07-30 04:46:46 UTC
take another and se first morning urine! How late are you? IF you are not late it may show only in the morning! Also, dont let the test set longer then the instrctions say too, as this can lead to an evaporation line! (a false positive) Test are not normally false positive... So I would say that you are pg good luck and congrats!
Panda
2007-07-30 04:44:36 UTC
You can get false negative pregnancy tests, but not usually false positive ones. It is possible that you miscarried, as one in three pregnancies is, especially very early on in the pregnancy, when most people haven't realised they're pregnant. The best thing to do is to get a test from your GP/clinic. You'll have to give a urine sample, but their tests are very accurate, and free.



Good luck x
2007-08-05 17:38:50 UTC
What time of the day did you take both tests? Because the first urine of the day (first thing in the morning) is more accurate as the concentration of the urine is higher, ergo the concentration of hCG is also higher and easier to detect. Certain medication such as Pregnyl, Profasi, Pergonal and ALP contain hCG and can therefore give false positives. I hope you get the outcome you desire
hectichold
2007-07-30 04:49:28 UTC
You absolutely CAN have a false positive pregnancy test!!! It happened to me. My false response came from the dr. office, NOT the home test!!! I'd either go to the doc or take another at home test. No need to wait weeks- you're either pregnant or your not.
sdc_99
2007-08-06 18:28:38 UTC
OK, if you were pregnant and miscarried, chances are the test would still have been positive - it takes a little while for your hormones to level out.



For your peace of mind, you might want to see a doctor for a blood test.
skyebby
2007-08-05 06:56:39 UTC
if the test says it it positive then i most likely is. your body will produce a hormone that ONLY present when expecting, if the test is negative its because the test hasn't picked up the hormone yet or its too early to tell.
2007-08-06 00:17:58 UTC
Nope.. Not likely to get a false positive... still having doubts... take several tests!
weeeelilbit
2007-08-06 11:25:52 UTC
IF YOU WANT TO KNOW FOR SURE YOU SHOULD GO TO THE DOCTORS. THAT'S WHAT I DID. I TOOK A HOME PREGNANCY TEST THAT SHOWED UP POSITIVE, BUT I WAN'T TO BE SURE. IT'S GOOD TO BE SURE THAT WAY YOU DON'T PUT THE BABY AT RISK LIKE IF YOU DRINK, DO DRUGS, HEAVY LIFTING, OR ARE VERY ACTIVE. REMEMBER THE BABY COMES FIRST.
2007-08-06 03:38:49 UTC
it'd be more common for the negative result to be false.. wait a week or so and try again, you don't usually get a false positive.. good luck, hope you get the result you want!!.x
CharlieWarlie
2007-07-30 09:30:14 UTC
no, the hormone that is tested for in a pregnancy test is only present when you're pregnant, although you can have a negative one and still be pregnant
redshoes805
2007-08-06 03:08:51 UTC
Go to your doctor and get one done there. They can also give you a blood test as well. They can tell from this as well.
2007-08-06 08:33:50 UTC
i tested myself 4 years ago two times it showed negative & i found out i was pegnant 3 months later.
2007-07-30 04:46:54 UTC
If you've recently miscarried, then you can get a false positive; otherwise, a positive is extremely accurate.
treaqq_love_1999
2007-08-04 19:36:16 UTC
wait a couple of weeks and test again and then if you have prego. symptoms still go to the doc. and get blood work done.
2007-07-30 04:49:55 UTC
after i have a misscarrige al test i done for six weeks come up postive becasue the hormone is still in your boby
mommy2408
2007-07-30 04:49:08 UTC
on the first one you may have read the results after the time limit and got the evporation line
2007-07-30 09:24:02 UTC
i would test at drs but yes u can have false poss i have few times
2007-08-03 19:40:01 UTC
yes i actually have had a false positive before they are rare but it can happen
Nicole E
2007-07-30 04:49:49 UTC
possbile but Unlikely


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