What could Cause a False Positive on a Pregnancy Test?
A pregnancy test taken at home can yield false positive results for several reasons. Even a pregnancy test performed on blood can show a false positive under certain circumstances. False positive are rare, but they do occur. Seeing a doctor soon after getting a positive pregnancy test result is always a good idea.
A home pregnancy test works by measuring Human Chorionic Gonadotropin (HCG). When a woman is pregnant, placenta produced to nourish the baby produces HCG in great volume. Normally most variants of the home pregnancy test cannot be considered accurate until taken on the date or a few days after a missed period.
One common corrupting agent to the pregnancy test is exposure to soaps or detergents. These can cause a false positive result. Thus urine collection should be done carefully to avoid such exposure. Many tests simply have one urinate directly on the stick used to give results. If one must urinate into a cup, the cup should be very clean and presumably free of any leftover soap or detergent deposits.
Another frequently common reason for a false positive pregnancy test is when women are using HCG injections in order to assist in getting pregnant. This means that HCG levels may register even when a pregnancy does not exist. Normally a blood test or obstetric examination helps to determine a true pregnancy from a false one. Theoretically, a man being injected with HCG could have a positive pregnancy test, even though one would know the man was not pregnant.
Other medications may also cause a false positive on a pregnancy test. These include anti-convulsants, medications to treat Parkinson’s disease, certain tranquilizers, and certain diuretics. Many of these medications could be dangerous to a growing unborn child, so it is very important to confirm results with an obstetrician if you are taking any of these medications.
Trophoblastic tumors, which grown in a woman’s reproductive system, may also yield a false positive on a pregnancy test. These tumors can also make someone feel pregnant, causing morning sickness and swelling in the abdomen. This is because they also produce HCG. When caught early, these tumors generally can be removed and cause no further problems.
In some cases, hysterical or false pregnancy can also produce HCG that will be detectable on a home pregnancy test. As with trophoblastic tumors, a woman may manifest pregnancy symptoms that make the pregnancy seem more plausible.
In all cases, a positive pregnancy test means seeing a doctor soon to discuss obstetric care and set up a plan for medically addressing the pregnancy. If you have any of the conditions or take any medications above that might corrupt the test, this should be brought to a doctor’s attention so the pregnancy can be verified.
Okay, so I have been on birth control for about a month now. Sometimes i would forget to take it so I would take a double dose or whatever the next time.
So, i had unprotected sex about two weeks ago and i missed my period when i was scheduled to have it. I am now showing signs of pregnancy and decided to take a pregnancy test. i took one and it showed up negative.
even fifteen minutes later, it stayed negative. i decided to take another one about two hours later and it showed up positive 10 minutes later. am i pregnant?
- anon64219
51
I had my tubes tied last april. I have had stomach pains since late January. I went to the emergency room and they said I had kidney stones. they did no xray and I missed my period for January. not sure so I went to ob/gyn and she ordered hcg testing to see if I am pregnant. this is just crazy.
- anon63370
50
I had a tubal ligation done 15 years ago. I went to the ER two days ago for severe stomach and lower back pain and was told by urine I was pregnant.
I made them test the blood and my Beta Hcg was 94 which is considered pregnant. Was told to repeat my Beta Hcg in 48 hours so I went today to get the test but my doctor left early so now i have to wait until Monday to find out if I am pregnant or not.
I did some research and found that after being fixed for 10-plus years your tubes can fuse/grow back together so pregnancy is possible.
- anon63011
49
i had a home pregnancy test three times and it came out positive but i don't have any symptoms at all. I am really scared.
- anon60820
48
I had a mishap and had to take plan b one morning. a week later I started what I thought was my period but i've been on it for two weeks now. it's not the shade that my period usually is, and two pregnancy tests are coming up positive.
I've been told I could have a cysts and also chemical pregnancy. Is it possible I'm not pregnant?
- anon60081
47
I have read everyone's comments and I'm still confused. i have had a kid myself and during that pregnancy i tested negative but i was for sure pregnant no doubt. Now my wife (yes lesbian couple) and i are trying again to have a baby, this time with her being pregnant.
she pulled a positive test one morning and a false all in the same day also. She went to the doctor the same day they said it was negative. we want to believe it's just too early to tell because they did all the tests to see why it might have been positive, such as infections, yeast infections, UTI etc. Any ideas?
- anon57216
46
About a year and a half ago, I passed out and just about had all pregnancy symptoms. Next day me and my hubby decided to take a test just to make sure and it came back positive! We were so unbelievably exited! So the next day came and we decided to take another and it was negative!
I was so confused then about a week later I started my period. It was devastating. The only thing I could think of was a chemical pregnancy. I've been trying for two and a half years with no success other than that positive test which ended up in me not even being pregnant.
- anon57215
45
If you have taken home tests and they came up positive, and the tests from your doctor came up negative and they said they couldn't find anything in your uterus, but the home tests are still coming up positive, it's possible you may have a tubal pregnancy. In that case, i would recommend bringing it up to your doctor immediately. It happened to my mom.
As for the comment about the dark blood coming out, a lot of times your body will just release old blood before your actual period, so unless you are experiencing a lot of pain i would assume your body is just releasing the old.
- anon57188
44
I was three weeks late, so I took a home test and it was negative. That same night I started bleeding. Two weeks later and I feel horrible nausea and vomiting, light headed, tired all the time. I took another home test and it was positive. Then I took another and it was negative. It is so confusing.
- anon56104
43
My x took a home pregnancy test that showed positive. I got back with her for the kid's sake because I believe every child should have a parent. Later took two more different tests that showed positive also.
We went to the doctor who also said she indeed was pregnant. Well after a hand injury, she went to the doctor and while doing an x-ray and ultra sound, they found a tumor. So she's not pregnant.
I'm worried for her health but don't know how our relationship will work. Plus, I'm actually afraid I could catch something but it could just be my ignorance.
- anon54882
42
i wasn't feeling too well one day and it was five days before my next period. my mom suggested that i take a pregnancy test and it came out positive. i then took two more digital pee tests and they said pregnant.
I had symptoms that go with pregnancy so i went to the doctor and got a blood test and it said i was pregnant.
Two days later i started spotting and then i started bleeding and i thought i was having a miscarriage. however, it was similar to my period. i was sent to the ER where they ran some hcg tests, just in case, at a different hospital only to find out that i was not pregnant. my hcg level was a ninw when a pregnant women in the first few weeks is anywhere from 45 to 300,000.
they said i was nowhere near to being pregnant.
why is it that i took different home pregnancy tests and they were all positive and a blood test at the doctor's office said positive and then a day later i get my period, it's not a miscarriage and it's declared that i never was pregnant?
the doctors were in shock and said i'm one in a million.
just thought people should know science isn't always right.
- anon53995
41
I started my period on Oct. 15. It was normal and it ended on the 18th. That night I had sex and then on saturday and sunday all was well. i think I was spotting -- it was this brownish discharge. It was really gross. well, happened again on wed and went to the doctor got a negative urine test. Then saturday and sunday, I spotted again with that brownish stuff and took another test which also came out negative. Haven't spotted since sunday and I am tired, really hungry, cramping and moody. What is going on?
- anon51500
40
I took five positive pregnancy tests all showing a faint positive. I had a blood test and today I was told it was only at 2mi HCG below 5 meaning not pregnant. You cannot believe home tests. It can be so heartbreaking. =(
- anon49039
39
i did a home pregnancy test two positives but don't have any symptoms. does that mean I am pregnant?
- anon47904
38
A year and a half ago i got my tubes tied. I was a few days late this month, and when i did get my period it lasted for only two days. It was moderate bleeding.I took a pregnancy test and i fainted when a plus sign showed up. Is there s chance i could be pregnant or is it just a false positive? Ive been experiencing tender breasts, headaches, nausea and light cramping.
- anon46040
37
My period was five days late, so I took two over the counter pregnancy tests, both which came out positive. The next morning, I started my period. I went to the doctor and took another pregnancy test which came out negative. Should I worry that something is wrong, or chalk it up to a faulty test?
- anon42345
36
i took the morning after pill about 3 weeks ago and my period turned out to be late. but i began spotting on the day i should have started my period. being a week late i took the home test and it came out positive. but i have all the signs of getting my period. could i really be pregnant?
- anon41557
35
I missed my period, so my boyfriend suggested I take a pregnancy test. The test I took surprisingly came out positive. I then panicked and took another test, which also came out positive. Then we did some research and found out that in the morning you get the best result of the pee test. So I took a third in the morning the next day. It also came out positive. I then made a doctor's appointment and went in for an observation as well as a pee and blood test. The pee test in the doctor's office came out negative, and the doctor told me she couldn't see anything in my uterus, so I gave blood and am now waiting on the result. However, I came home and have taken twomore tests since the doctor's which both came out positive. Basically I have now taken five at home tests which were different brands which came out positive, but the one test taken at the doctor's is negative. I am so frustrated, we really want a baby. Do you think I am pregnant? Or could there be a chance the blood will come back negative also?
- anon41012
34
I always get positive results in pregnancy tests. i can never trust them. i have to go get a blood test every time i have a scare. i'm *never* ever late on my period and i'm a week and a half late. i took a test and it came out positive. i went to the doctor and got a blood test and theirs came out negative. never trust over the counter stuff.
- anon40348
33
Dude, if a guy tests positive on a home pregnancy test then he needs to see his doctor. Testicular cancer can cause a positive pregnancy test reading!
- anon39487
32
false positives are more common than they think, i figure. i took 3 home pregnancy tests, EPT - and they all came up positive. i went to the doctor to have it confirmed, and they tested me 3 times, all negative. i came home and took another home test that came up negative. bottom line is, they can't be trusted. just go to the doctor.
- anon39456
31
yea a pregnant woman can test negative. i tried being male i tested positive. whats up other than screwy tests likely contaminated through shipping
- anon38025
30
i took a a couple of home tests after not geting my period for about 2 months and they read negative. now recently i have taken a another home test that read positive. after seeing my doctor i had an ultrasound and they could see nothing. i got nervous so i went home and took another home test and it came back negative. now does this mean i had a false positive or a miscarriage
- anon36781
29
Can you get a false positive five months after giving birth?
- anon35804
28
I took a test about 4:30 today & it came up saying that in not pregnant, but I just looked at it again at about 10 and now it says I am.
Could it be a false positive?
- wowwhattodo
27
I am tired of all the wrong results! I am a guy and I am even more worried for my girl than she is for herself!
She keeps having side effects which seem like pregnancy to me. The other day, she had a negative, 2 days later on a different test, she had positive. A day or 2 later, she came up with 2 negatives. This is so confusing!
She says she is fine and that it probably was a false positive but I am insisting on a docs appointment!
Do you think she is negative? and I don't think she has a period bc she is on the monthly pill or something like that.
- anon29452
26
Mizlopez90, it's possible that you may have had a miscarriage.
It's possible you took the test earlier than your late period. If you hadn't taken the test, you wouldn't have known anything was happening at all.
- anon28920
25
I have been off birth control for about 2 months now and I haven't had a period since January. I have taken 9 home pregnancy tests. Do you think I am pregnant or can stress or being on tetracycline make a difference?
- kalicia
24
my period was about a week and a half late this month and I took a pregnancy test. it showed up positive. you cant misread this test it shows up *pregnant or not pregnant*. two days later I started bleeding heavily. I went to the doctor. he did a blood test and he said i wasn't pregnant ...i'm sooo confused!!!!!!!
- mizlopez90
23
i did a home pregnancy test which came out positive. i also went to the doctor who confirmed same. about three months later i started spotting and the doctor sent me to do an ultrasound which confirmed that i have only an empty sac. is this possible and how can that be?
- anon26831
22
i had 2 positive urine home pregnancy tests. the 2nd line in both came up almost immediately, but were quite light. now it seems as if i have started my period. i'm not to sure if i can still be pregnant or not.
- anon26041
21
Thanks for the article. It does help answer the question I posted 3 weeks ago, about false positive results. My case, however, ended up being a pregnancy. I found out at almost 6.5 weeks, but ended up losing it a week a half later.
- cookie38
20
i took a pregnancy test and it read negative. then yesterday (a week later) i took one and it read positive. we've been trying to get pregnant for a while and i'm worried about going to the doctor and having them tell me that i'm not preg. and that it was a false positive. i haven't had a period since september and it is now december but i was blaming that on the fact that i just recently stopped taking the birth control shot and that causes irregular periods. i have taken 3 or 4 tests since september and this is the first positive. i am not experiencing any symptoms other than cramping without bleeding which has been happening for almost 2 weeks. has anyone ever had a false positive or does anyone think i really am preg? i wont be able to go to the dr until friday and the suspense is killing me!! ur advice and comments would be greatly appreciated
- nell50
18
Help. I just took a test and came out positive. I had a heavy cycle 18 days ago, and 2 weeks later, thought I had a period but only lasted a day. I've had brown discharges for the last 3 days since. Have not been active since before cycle. Could this be that trophoblastic disease? I have kids, and have never had this happen. I don't think I'm pregnant, but can't figure out why this came out positive. Am waiting for the doc to call back.
- cookie38
17
Monday October 6th, I took a pregnancy test. It came out positive. I took three more to see if it was actually happening. So two days later I took another two and both came out negative. I'm completely confused. What could be going on?
- anon19259
16
ok ive had 5 home pregnancy test come up positive and they were 3 different brands. i been to birth right twice and both of their test came up negative. the home test that i had were the kind that you pee on the stick. the kinda at birth right was the ones that u got to pee in a cup and then they use drops of it. what is the deal???
- anon19026
15
I have a friend who is pregnant and just had a blood test confirmed on 9/29 today she calls me and tells me her doctor is ordering a second blood test because a medicine she was on may have caused a false positive. The name of the medicine is Geodon Ex! Does anyone know because what I have found out so far the doc is pulling her leg.
- anon18942
13
anon16137: i would go with the most recent positive result on your pregnancy test. you may have taken the previously negative test too early, and your body didn't have high enough levels of hcG in your urine. once your body produced enough of it, the home pregnancy test was able to detect it. i would suggest taking another test, although false positives are pretty rare. also, make an appointment with your ob/gyn for confirmation and to begin prenatal care if you are pregnant.
- sunrisesunset
12
i took a pregnancy test and at the time it turned negative i went back some time later and it said positive so what do i go with?
- anon16137
10
well i have irregular periods...skip a month here and there and the length of my period changes....so i wasn't really worried when my last period was in february...until i started to getting nausea around the end of march beginning of april...a took three pregnancy test and they all came out positive...is there a chance that they could be wrong...
- anon12176
9
I thought I was pregnant for an entire day due to a false positive on a test at my doctor's office. However, they also drew blood and did a test which came out with zero presence HCG. I am still having all the signs, throwing up, sore, swollen breasts/erect, enlarged nipples. I have 3 children. I know what pregnant is like.
I just can't figure it out. I did not want to be pregnant until I found out I was, only to have it ripped away from me. They can give me no answers. Anyone else ever had this happen and still had a baby? They said the blood test they performed is conclusive but I honestly wonder if they got my blood mixed around with someone elses?
This is just awful. If I am not pregnant then these symptoms need to disappear. I would be about 4 weeks. They did an ultrasound the first day on the suspicion of it being a tubal but saw nothing. At 4 weeks you can't see anything uterine anyway.
I am just dumbfounded. Feel like I am literally losing my mind.
- anon11424
8
My last period was Feb. 24th, 2008, Then I was off the pill for a month, waiting for my appt to get a refill, I saw the Dr. on March 18th and also got the first shot of the Gardisil Vaccine. Could the Vaccine cause a false positive? and if I am pregnant do you know the risks of this vaccine, I have read horrible stories of miscarrying. Thank you
- anon10409
7
my wife got urine test positive on 2-02-08. Same day doctor was consulted. pregnyl 10000 dose was given. Endometrial thickness was 19mm on 13-02 08 and beta hcg on 15-02-08 was 1280 units. Despite all this ultrasound didn't show any activity. We are puzzled. Help.
dharesh
- anon8993
6
slrosemead:
spotting in the first trimester of pregnancy is fairly common, and a lot of women go on to carry their babies to full term with no complications. with all three of my pregnancies, i had some light spotting around the time i should've had my period. you should be particularly concerned if the bleeding is heavy, bright red, and accompanied by cramping. call your doctor immediately to be checked out. good luck!
- olittlewood
5
Yesterday afternoon my gynecologist doctor said I was pregnant after a positive urine test. However, today I started my period, what could be the matter?
- slrosemead
4
I went to the gynecologist yesterday for a pap smear. After taking a urine sample the doctor informed me that I was pregnant. Since I have had trouble conceiving I asked her to perform a blood test. Although she allowed the blood test she advised me to just accept the fact that I was indeed pregnant. The problem is that today I started my period. Do you think it is just a false positive or can a person have regular menstrual bleeding while pregnant??
- anon7370
3
I suggest remaining calm and not causing any further distress by worrying. Yes, it is difficult to imagine, being anxious is a natural reaction to such indications. I simply suggest relaxing due to the fact that worrying about it isn't going to change anything.
- anon2512
2
Had some bleeding from somewhere not normal a year ago. Never got it checked out, it went away on its own. That was a year ago. Just this past january i had my period for 5 days- normal. Skipped 2 days then i started having severe pains and spotting for a week. I know i should have gone to a doctor then but i didn't have insurance so i didn't. Then it all stopped for a few days and about the 5th of february i got my period for 15 days in a row and haven't had it since then. 2 pregnancy tests show positive but i am afraid to tell anyone i know until my doc. appointment on the 29th because i think the abnormal bleeding i saw last year could mean a tumor like your article talked about. i do feel pregnancy symptoms but i am still doubtful. i have been trying for 6 years. if the doctor thinks i am 18 weeks along possibly , then why are they making me wait until june 29th to see a doctor?? advice?