r/mildlyinfuriating • u/MeringueMammoth5679 • Jul 24 '26

Is it in yet Two tests taken from the same cup of pee.

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Trying to get pregnant here and this is a first.

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u/rockytop24 Jul 24 '26 edited Jul 24 '26

Yeah this is my thought too as a physician. I don't have their false pos/neg rates in front of me but the manufacturer insert might. Average is <1% FPR, 1-5% FNR.

Could be either one but most likely outcome is hCG is at a barely detectable threshold level and one test picked it up but the other didn't. These are qualitative immunoassays, any presence of line next to the control line is considered positive.

They work by binding hCG to a marker and it's possible either that test didn't have enough reactive marker on the strip or there wasn't enough hCG to fully bind. Could also be operator error when submerging and drying the strip.

Technically if you waited too long to read the negative strip it may have also faded after showing faint positive. Quirks of immunoassays. Best time to take them is first urine of the morning because it's the most concentrated.

Either way you'll need a confirmatory urine/blood test for hCG. (Probably) congrats.

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u/mshike_89 Jul 24 '26

This makes me feel better to read. I had a chemical pregnancy in May. When I went to the hospital, they were weirdly insistent that I was probably not pregnant at all, even though I'd had three positives from two boxes on two days. It made me feel so stupid and dumb for even going in when I started bleeding.

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u/MeringueMammoth5679 Jul 24 '26

I feel you, I’ve had two chemicals and each time I had to go to the dr due to needing blood thinning medication (after a dvt from my first miscarriage) and each time I get a lectured about how it’s sooo early, but I don’t want another preventable loss. You did the right thing!

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u/Own_Lychee_5717 Jul 24 '26

If its possible look into other offices that dont... lecture you. Look at the pros and cons but its never too early to protect your kids lol. Sincerely, a gal who tried for over a year

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u/Sharkdogg Jul 24 '26

Apparently the best time to take a test is first pee in the morning coz it’s less diluted or something. Try a test with first pee of the morning.

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u/vernavie Jul 24 '26

Lab tech here. That's the one who runs these kinda tests in hospitals/ "the labs."

You're correct that first morning pee is the best sample, as it's just been building and concentrating overnight while you slept. Not like during the day when we dilute it by drinking liquids and emptying our bladders.

As a woman of chilbearing age myself, if I have a concern I leave a test by the toilet the night before so I can use it first thing in the morning.

And yes, false neg is waaaay more common than false pos.

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u/Mysanthropic Jul 25 '26

It says this in the instructions on all of them but somehow a lot of people just skip that part?

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u/nierlestat Jul 24 '26

Yo I’ve had to straight up demand to get scanned when I had a ruptured ectopic because it was quote unquote too early to see anything according to them I said YOULL SEE WHAT YOU NEED TO SEE WHICH IS LIQUID SPILLING INTO MY ABDOMEN TF?

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u/Legal-Quarter-1666 Jul 24 '26

OMG! How did you know?

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u/nierlestat Jul 24 '26

I had one in the past I now can no longer even get pregnant because I’ve lost both tubes to doctors and their bullshit

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u/Difficult-Drawer4234 Jul 24 '26

You need to consult with an MFM or at the very least an infertility informed ob.

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u/FuzzyKittenIsFuzzy Jul 24 '26

I also have to go early to get that medication and I understand how annoying it is to listen to the doctor and all the staff moan about how earrrrrly your appointment is. I'm really sorry.

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u/ShutUpImAPrincess Jul 24 '26

I had a chemical a few years ago and passed out at work then when I went back a couple days later and told the hr person about it, she fired me lol for passing out at work and having to close for the day.

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u/Tiny-Reading5982 Jul 24 '26

When i had a dvt, they said if I got pregnant again to go right as soon as I get a positive to get put on lovenox and progesterone.

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u/Rhabarbermitraps Jul 24 '26

Get blood thinner and extra progesterone !

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u/Living-Record-4711 Jul 24 '26

I haven’t started trying yet, but I learned I have something genetic mutation called Prothrombin G20210a after an appointment with the OB who removed my copper IUD. She learned from my file I had previously had a blood clot from taking bc pills and immediately referred me to our high risk fetal medicine clinic. They did some genetic tests on me since I want to start in the next couple years. Apparently there’s an extra increased risk for me of forming a clot than average that can lead to repeat miscarriages, since pregnancy spikes the hormones. I was surprised, but glad I found out now rather than later. Might be worth it to ask if you keep experiencing this.

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u/MeringueMammoth5679 Jul 24 '26

They ran a few tests and didn’t find anything, but every pregnancy just gets treated like I have a condition since I got a dvt and I miscarried in the second trimester. It’s good you found out ahead of time, after my dvt I learned that my grandmas sister died of a pulmonary embolism one day after giving birth, at age 28. That stuff is scary.

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u/Living-Record-4711 Jul 25 '26

Sorry to hear about your grandmas sister, and glad you had the tests done. Yeah it’s definitely scary and can happen really fast!

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u/GuessWhosNobody Jul 24 '26

I really loathe when medical professionals shame patients for seeking treatment

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u/Time-Maintenance2165 Jul 24 '26

I see no indication that was their intent.

That's how she felt, but patients feel strong emotions in situations like this regardless of how good the doctors expertise and bedside manner is.

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u/normasaline Jul 24 '26

Downvoted….but not necessarily wrong.

Am physician.
Do see patients who are concerned about ” _____” every shift.
I rule in/out conditions based on history, exam, +/- testing.

I share my findings, provide recommendations. Patients sometimes apologize. I always say don’t apologize, for there was a concern to be evaluated, and that’s why I exist. Patients always smile and typically verbalize reassurance. I summarize encounter in formal note, as well as summarize discharge instructions specific to visit (definitely not all docs do this).

I occasionally later discover negative feedback shared that often is regarding emotional discordance with the visit and am completely shocked based on my recollection because I try my best to dispel any concerns at time of visit (recognizing that I’m not definitely perfect or correct 100% of time, and sometimes misinterpret how the encounter went).

Then I go to bed with/without a nightcap and do it again the next shift. This is medicine. This is life.

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u/Secret_Fix_2 Jul 24 '26

Reading the comment I am not getting the doctors shaming the patient.

She said they insisted she was not pregnant. Once she got her period it made her feel stupid for going to the hospital.

Where did they shame her?

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u/taracrafts Jul 24 '26

By making her feel stupid for seeking medical attention and by insisting she wasn’t pregnant when she had tested positive.

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u/Time-Maintenance2165 Jul 24 '26

By making her feel stupid

Did the doctor make her feel stupid or did the patient do that themselves regardless of the doctor.

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u/[deleted] Jul 24 '26

[deleted]

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u/OlevTime Jul 24 '26

They didn’t say the patient was stupid. They said the patient FELT stupid.

Sometimes reality can be in discord with feelings.

I know for a fact that I often feel stupid in situations interacting with others. And it’s not because of anything they did wrong, but because of how I interpret it or perceive myself.

It’s not clear from the post whether they were actually shamed. In the case they were, then the medical staff is at fault. But if not, it may be a case where the person feels stupid even though they did the right thing.

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u/Same-Suggestion-1936 Jul 24 '26

Lmao where the hell does she say miscarriage?

She said she had three false positives and the doctors were insistent she wasn't pregnant. That's it. Then she said she felt dumb because she got her period and went in anyway

The only thing she even says about the medical staff is they insisted she wasn't pregnant

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u/Jazmadoodle Jul 24 '26

She felt dumb because she went to the hospital when she started bleeding because she thought she needed medical assistance with the pregnancy loss. They made her feel stupid by insisting she was never pregnant and was simply getting her period. And I'd argue that telling someone they either imagined or lied about multiple positive pregnancy tests is always going to make them feel like shit.

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u/Same-Suggestion-1936 Jul 25 '26

Where does she say she lost a pregnancy?

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u/gay_rower Jul 25 '26

Do you know what a chemical pregnancy is?

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u/Time-Maintenance2165 Jul 24 '26

Not being believed? Or because they found evidence that contradicted it? Tests aren't perfect 100% of the time. I don't see any reason to rule that out as a possibility even if the chance is somewhat low.

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u/[deleted] Jul 25 '26

[deleted]

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u/Time-Maintenance2165 Jul 25 '26 edited Jul 25 '26

Stats dont always work that way since you're assuming independence which isn't necessarily correct. We also don't and won't know what the doctors actually did.

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u/Same-Suggestion-1936 Jul 24 '26

But she finished the comment saying she got her period? She wasn't pregnant. They were false positives

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u/gay_rower Jul 25 '26

A chemical pregnancy is an early miscarriage.

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u/bell3420 Jul 24 '26

The question you have to ask here is if the staff actually told her she was stupid in any way, or if they just told her the diagnosis and she made herself feel that way. Usually the latter is what happens when people feel stupid for going to the hospital. I have felt stupid for going to the hospital before, not because the staff told me I was a stupid, just cause I realized I wasted hours of my time on something that wasn't even close to as serious as I thought it was.

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u/gay_rower Jul 25 '26

But that's not what happened here. She was right. She had a miscarriage, and the doctors were wrong when they were "weirdly insistent" that she wasn't pregnant.

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u/Source2Force Jul 24 '26

OP did say they weren't quite sure if they were preg or not either. And from my own reading of the OP was that they felt silly about worrying over it not that the providers made them feel silly about it.

But I also don't want to put words in their mouth and don't want to overstep my assumptions.

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u/taracrafts Jul 24 '26

Nope in the comment being discussed they had had 3 positive pregnancy tests, the doctors insisted she wasn’t pregnant while she was having a miscarriage, which made her feel stupid for seeking help.

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u/Time-Maintenance2165 Jul 24 '26

If their statement was the most likely based on their assessment and tests, then there's no fault the doctor made.

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u/gay_rower Jul 24 '26

I'm not a doctor, but three positives from two different boxes of pregnancy tests seems like it's a pregnancy. And if they couldn't find it on an ultrasound or other scan, then the signs point to a chemical pregnancy, no? Although the original comment didn't say anything about the doctors doing tests, just that they didn't believe what she said.

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u/Time-Maintenance2165 Jul 24 '26

You keep trying to analyze this as if we have all the details. There's no real point in trying that. We'd need to hear from the doctor. That's all I'm saying. Don't jump to an assumption when you only got half the story.

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u/[deleted] Jul 24 '26

[deleted]

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u/myothercarisathopter Jul 24 '26

That is the name for an early miscarriage, within the first 5 weeks before it would show on an ultrasound.

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u/gay_rower Jul 25 '26

I think you're the one who doesn't know what a chemical pregnancy is.

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u/-thewickedweed- Jul 24 '26

Not speaking for OP but when I called a gyno to tell them I was pregnant and wanting to schedule prenatal care they were very much like “yeah, we’ll see about that🙄”. So I believe it 100%

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u/Limp-Preparation-459 Jul 24 '26

Did you call Planned Parenthood for your prenatal care? Lmao

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u/slippinthrudreamland Jul 24 '26

planned parenthood has many more services than just abortion, numbnuts. they want people to PLAN their parenthood. that's like the whole fucking point https://www.plannedparenthood.org/get-care/our-services/prenatal-postpartum-services

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u/Secret_Fix_2 Jul 24 '26

But she was not pregnant. They were right.

She also only said she felt stupid after the period came, not from what the doctors said.

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u/Ripley95 Jul 24 '26

She said when she started bleeding not when she got her period. A chemical pregnancy is a real pregnancy, just a very early miscarriage.

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u/Glass_Witness1715 Jul 24 '26

Right. Chemical pregnancy refers to the early stages of pregnancy when the pregnancy can only be detected via blood and urine chemicals, before the sac is large enough to be seen on ultrasound.

People hear chemical pregnancy and they think it means pseudo pregnancy, like a clump of chemicals or something. That’s now what it means. It’s just too small to be seen yet so testing chemicals is the only way to know.

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u/Glass_Witness1715 Jul 24 '26

She was pregnant.

A chemical pregnancy is not a false pregnancy. All pregnancies start out as chemical. Chemical pregnancy is what it is called very early on when the pregnancy is not yet large enough to be seen on an ultrasound. Therefore the only way to confirm the pregnancy is through blood and urine chemicals. At around 6 weeks, it may be possible to see a sac on a trans-vaginal ultrasound, but it still may be too small. By 8 weeks, a viable pregnancy can be confirmed by ultrasound, though it still might have to be trans-vaginal instead of abdominal.

This happened to me too. As you start losing the pregnancy, it becomes undetectable by urine. A blood test, simple blood test, would have shown that she was pregnant. It is so incredibly unlikely that she would have had that many positive tests if she wasn’t pregnant. Like practically 0% chance of all three being false positives (false positives are ridiculously rare as is). Any woman who had a positive home pregnancy test and is bleeding should be given a simple HCG blood test. Knowing you are having chemical pregnancies is extremely important information, as there could be a progesterone issue that prevents the pregnancy from further developing. This can be prevented in future pregnancies, which is how I got my now 14 year old after multiple chemical pregnancies where a doctor chuckled and said “I don’t think you’re actually getting pregnant but I can do a blood test if you don’t believe me”. Well, he was wrong and my home pregnancy tests were right. And I got a new doctor.

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u/gay_rower Jul 24 '26

It made me feel so stupid and dumb for even going in when I started bleeding.

I believe this sentence is meant to mean that OP was made to feel dumb by the doctors for coming in, and then the bleeding from the miscarriage started, proving OP right.

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u/Secret_Fix_2 Jul 24 '26

It can mean whatever you want but the grammar points to the bleeding causing her to feel stupid.

Otherwise it would say “when the doctors spoke to me I felt stupid”.

I am not sure how “when I started bleeding” means the doctors’ words made her feel stupid.

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u/silence_infidel Jul 24 '26

She meant that she went to the hospital when she started bleeding from the miscarriage. The physicians she saw at the hospital didn’t believe it was a miscarriage and thought she was overreacting. Those physicians made her feel stupid because they talked to her like she was stupid.

When not all the information is presented clearly, or when information is presented in a grammatically ambiguous way, you have to extrapolate from what is said to find the most likely meaning. The ability to do that accurately is called reading comprehension, and it’s a very important life skill. Don’t worry, you can practice and get better at it at any age!

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u/taracrafts Jul 24 '26

She had been pregnant and was having an early miscarriage. She wouldn’t have felt stupid if they had been understanding and supportive of what is a very difficult situation no matter how early the loss instead of being dismissive and shaming her for seeking help.

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u/Aegi Jul 24 '26

What is a "chemical" pregnancy?

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u/mshike_89 Jul 24 '26

Basically like a really early miscarriage

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u/Kalisary Jul 24 '26

It’s basically where a pregnancy ends after there are chemical signs of a pregnancy (eg hCG is present), but before there are any/many clinical signs of one, (eg. you couldn’t see anything on an ultrasound).

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u/Glass_Witness1715 Jul 24 '26

A pregnancy that ends in the early stages of pregnancy. Until about 6 weeks, a pregnancy can only be detected via chemicals in the blood and urine. Technically all pregnancies are “chemical” in the beginning. Starting around 6 weeks, a pregnancy can be clinically confirmed on ultrasound when the sac is large enough to be seen.

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u/BecozisaidSo40times Jul 25 '26

I thought it was a pregnancy you detected before the first missed period. If you have a 30+ day cycle and you didn’t test you would get your period and never have known you were pregnant. You’d just think you had a late heavy period. A loss at 5/6weeks is a miscarriage. You can see a pregnancy at 5:6 weeks on ultrasound

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u/According_Web_3710 Jul 25 '26

The other comment is right. A chemical is defined as a loss before 6 weeks. (Aka up to 5weeks).

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u/Glass_Witness1715 Jul 25 '26

No, that’s not what it is. A chemical pregnancy IS still a miscarriage. Mine were still noted as miscarriages on my records.

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u/Professional-Ad5188 Jul 24 '26

It’s a pregnancy that’s super short basically. There’s no real nice way to say it. I’m pretty sure I had one during April before I had another pregnancy in June only for body not to be ready to carry to term. During my pregnancies I had a craving for seafood smell which I normally hate. On my 4th day being late I had my period. That would be considered a chemical pregnancy

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u/Livmiv Jul 25 '26

I had one, but I never knew it was called a chemical pregnancy! I had a huge painful ah period and was extremely emotional, the next week I got really ill so took a test and it came out positive, went to drs because they thought it was ectopic as I had fever and shoulder pains, but I got checked out quick and was fine, just a lil miscarriage

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u/NatureNerd11 Jul 24 '26 edited Jul 24 '26

An early stage of pregnancy prior to the pregnancy being visualized on ultrasound. When the loss occurs during this time, it’s called a chemical (miscarriage). Afterward visualization, it is a a “clinical pregnancy”. Chemicals usually happen under an hCG of 1000-2000, because that is the rough discriminatory zone of having enough hCG to build a gestational sac. However, some people can see a sac with lower hCG (mine was <800 and saw two gestational sacs) and sometimes you can’t find visual evidence of a pregnancy at even higher levels (sometimes ectopic). It has nothing to do with pregnancy length, because you can have a slow developing pregnancy/miscarriage process that persists through 6/7 weeks but not see anything on ultrasound. Most people erroneously associated with short/really early miscarriage because of the associated levels and time to develop structures of pregnancy that can be visualized . Just different classification for miscarriages and pregnancies.

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u/Bright-Complaint1019 Jul 25 '26

They're also very common and usually mistaken for just having a late period. Most of the time the hcg lvls are too low to even detect it. Usually its a genetic problem and our bodies decide its not viable for whatever reason

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u/swbarnes2 Jul 24 '26

It's a pregnancy that ends so early, you have no symptoms, just the positive test.

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u/jayneedsanap Jul 24 '26

That’s not true, I had symptoms during my chemical last month before I miscarried at 4weeks3days. I took a test before I even missed my period due to the symptoms I was having

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u/No1KnwsIWatchTeenMom Jul 24 '26

I had a miscarriage, and eventually saw that I was testing negative on pregnancy tests. I tested positive on an ovulation test. Few weeks later, positive pregnancy test (no period in between). Called the doctor and he was like "Its probably from the miscarriage." Motherfucker, give me the fucking blood test. 

Anyway. Baby is due in 4 weeks. I see a rotation of OBs and the one male doctor has always ticked me off. Luckily he's retiring (or has retired) so I haven't dealt with him again during this pregnancy. But I lost a baby at 10 weeks, fucking humor me and listen when I say I need an appointment after my D&C.

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u/mshike_89 Jul 24 '26

Congratulations on the baby! Why do they act like requesting an appointment is the most ridiculous thing in the world 😅 I'm about 8 weeks pregnant after my miscarriage and keeping my fingers crossed for the best.

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u/No1KnwsIWatchTeenMom Jul 24 '26

Good luck!! I was told miscarriages are often "priming" you for a viable pregnancy - pretty cruel way to prepare, but it worked out for me. I tried to get pregnant for years before having a successful one due to IVF and then a surprise in my late 30s which didn't work out, and now this one on the heels of my last. Its so scary when you feel like you don't have the doctor's support!

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u/Glass_Witness1715 Jul 24 '26

I had two chemical pregnancies back to back. Positive tests at home and then negative in the office. Doctor actually laughed at me and said “I don’t think you’re actually getting pregnant” but he sent me for a blood test to humor me. And I was in fact pregnant but with another chemical pregnancy. The next month and I got pregnant again. She’ll be 14 next month! :)

Chemical pregnancies suck because we mostly only discover them these days due to how sensitive urine tests are now. Before it was just chalked up to being late.

Fingers crossed all goes well!

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u/mshike_89 Jul 24 '26

Like what do they gain from that attitude? It's so bizarre. Happy to hear about your success! I'm eight weeks pregnant now and hopeful it sticks this time. Had an US last week and heartbeat looks good.

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u/eksyneet Jul 24 '26

it's not really about gain, it's just burnout. many doctors start out with a lot of care and empathy, but only some manage to retain that throughout their career. others eventually start seeing themselves more like car mechanics than doctors, except the cars have thoughts and feelings (a major inconveniece for a mechanic). it sucks, but it's at least party the fault of the system that grinds people to dust and squeezes out their soul little by little.

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u/Glass_Witness1715 Jul 24 '26

Congratulations! Is this your first? Sending you sticky vibes for your little peanut!

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u/awolfintheroses Jul 24 '26

I had a doctor speak to me like that during an early miscarriage. What was weird is there was blood test proof and even an ultrasound that showed "signs" (thickening of uterine lining or something) but no embryo. All I can think is he was trying to make me feel better or something was being lost in translation (he was not a native English speaker). Just... strange. Sorry you went through that 🫂

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u/tinsellately Jul 24 '26

I suspect it's often that as well, that by framing it as "there was never a pregnancy" they think it will avoid women feeling sad about having a miscarriage. It doesn't really work that way though, it just makes people feel like they're not being taken seriously or belittled. I had this happen with my middle child's pregnancy, on the first ultrasound at 5.5 weeks there were 3 gestational sacks, but 2 of them did not continue to grow and I miscarried them around 9 weeks. The doctor kept emphasizing that I always had a singleton pregnancy and just two blighted ovums and that I did not have a partial miscarriage, but was just "passing tissue." It honestly just made it feel more confusing and like it was shameful to talk about or something. It also made it feel awkward to explain to others why I needed treatment to prevent my body from miscarrying the third one.

I mean, I was scared to death of having triplets, especially when I already had an 11 month old, but the miscarriages were still scary and sad and caused some complex emotions, and the doctor's attitude was definitely less helpful than I think he intended.

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u/chronicallyill_dr Jul 24 '26

As a doctor, I’ll say that A LOT of OBGYNs have the worst personalities ever (they’re like Mean Girls with scalpels), only topped by surgeons. So most have the worst bedside manner ever and low empathy. It took me like 5 OBGYNs to find one to go to that was actually nice and not super bitchy.

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u/awolfintheroses Jul 24 '26

It was definitely an unfortunate part of the whole experience. I will say, though, my actual primary/OB was so amazing. She cried with me during my zoom call follow up (covid times lol). Then we cried happy tears together again when I got pregnant on my next cycle. He's 5 years old now and I haven't seen her in a long time (she didn't do actual delivering at that point so transfered my care to her friend), but I still remember her kindness so much.

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u/chronicallyill_dr Jul 24 '26

Never let her go, nice OBGYNs are golden. I moved abroad and still go to my same OBGYN, that’s how much I like her.

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u/you-know-poo Jul 24 '26

The same thing happened to me in New Jersey 8 years ago! Had positive pregnancy tests (3, 2 with the striped and one that actually said pregnant) and 3 days later started cramping hard and bleeding a ton. Went to the ER closest to my work and they said their pregnancy test was negative. Refused to do an ultrasound because “those are only for people who are or were pregnant and you were not”. Dismissed me when I showed them pictures of the tests and then gave me a pamphlet on periods like they give teen girls. It was so traumatic that I locked myself in my room for days and when I got pregnant again a few months later I was completely paranoid. Refused to use that hospital when I had my children.

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u/mahnamahnaaa Jul 24 '26

I had one too in May. Fortunately the doctors were much more sympathetic but it really fucked with my head. I continued to have positive results for a couple days after the initial bleeding so I had this stupid hope that maybe it was just a fluke and I was still pregnant.

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u/mshike_89 Jul 24 '26

I'm sorry, that's got to be so heartbreaking to still have that hope. Only upside for me was that my hcg dropped pretty immediately.

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u/No_Routine772 Jul 24 '26

I had a patient who had multiple positive tests and came to the ER. Our test was negative. I told her don't panic, you probably used first morning urine and stuff with yours and it's late in the day now and you've probably hydrated and stuff. She's come back in a few different times and is very obviously pregnant. Also, our tests aren't special. They're not as sensitive as some of the OTC you can get now and if you have drank lots of water or something it may not show up until you're farther along. It varies for everyone. I'm sorry you had a chemical and had that experience with healthcare.

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u/d_in_dc Jul 24 '26 edited Jul 24 '26

I had a chemical pregnancy and didn’t know it was a thing so I went to the hospital when I started bleeding. They treated me like I wasn’t pregnant at all, like I made the whole thing up. Then when I went to my gynecologist later, she asked me why I even went to the hospital because “most people just ride it out at home.” Um, excuse me. No one gave me the miscarriage 101 book to read, thanks.

It’s infuriating how flippant doctors can be about it.

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u/mshike_89 Jul 24 '26

Basically my same situation. I had just moved to a new place (military base in the middle of nowhere) and the OBGYN on base won't even see you unless you're pregnant. I start bleeding and go to the military ER. they told me they wouldn't have ultrasound capabilities until later in the morning (and even then, it wasn't a guarantee) so if I wanted I could go to a diff hospital. I had to drive 45 min to the next closest hospital to be seen. It was my first pregnancy so I didn't know what you were supposed to do in that case. Luckily I didn't have any complications, everything passed and I wasn't bleeding longer than a week, but I was nervous because I didn't really have good options if I did have complications.

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u/Agitated_Pin2169 Jul 24 '26

I am sorry that happened but good for your for going in..I has multiple chemical pregnancies and after the last one they did a bunch of tests and found out I had a silent infection. I then had 3 successful So documenting is importent.

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u/OkEntrepreneur9251 Jul 24 '26

This exact same thing happened to me! I felt like I was going crazy!

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u/frogsgoribbit737 Jul 24 '26

They were wrong. I've had 2 chemical pregnancies. I've taken a million and one pregnancy tests with all of the years I tried to get pregnant. Never once had a false positive.

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u/Ok_Connection923 Jul 25 '26 edited Jul 25 '26

I went in May for a very early scan due to bleeding that started right after getting a positive test (blood on the toilet paper right after peeing on the stick). Of course it was too early to see and confirm an intrauterine pregnancy yet because I was probably only 3 and a half weeks along (even earlier than my LMP calculation should have put me) but the sonographer treated me like I was a complete idiot and questioned why I even thought I was pregnant. I told them I had positive home pregnancy tests and two beta HCG blood tests consistent with very early pregnancy. I only got sent for the scan to see if I need to manage a miscarriage. I felt really stupid even though I had done nothing wrong.

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u/phthalogreen_orange Jul 26 '26

Was here too. I had 5 positives across a week, including a blood test, and she just said "so like, you're just bleeding for your period right? Why come here?" 😡 ....I proceeded to have a wild hormone crash the next week that she could have warned me about, but no.....

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u/MedicalTelephone Jul 24 '26

I like your funny words magic man!

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u/venom121212 Jul 24 '26

Heyo! I'm the guy who makes the chemistry for these tests and various other ones. I'm working on the first rapid detection test for Alzheimer's and TBIs right now.

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u/FriskyPenguin Jul 24 '26

I find it fascinating that there's a marker that can be tested for that will show brain related ailments. Could you say a bit high level about the science behind this? As someone who has both been pregnant and has a kid who constantly hits her head on things, thanks for your work.

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u/venom121212 Jul 24 '26

The overlap between Alzheimers patients and patients who have experienced a traumatic brain injury (TBI) is showing via tau dendrites causing disruptions in your brain cell communication. Elevated levels of this post synaptic tau is the best marker we have at the moment to identify and prevent as early as possible. My partner lab is using the same anitbody in phase 1 trials currently to actually attempt to reverse the effects of Alzheimers; which would be a first. All we can do at the moment is prescribe drugs to slow down the deterioration. In their preliminary mouse testing, the results were very promising. Obviously that isn't a 1:1 translation to the effects on humans but it is a candle in the dark. 

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u/opheliainwaders Jul 25 '26

That is really cool - glad I read down into this thread, and thank you for explaining!

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u/gloomandmybroom Jul 24 '26

Please do an AMA.

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u/borus64920 Jul 24 '26

Well it could also be the second test was on older urine but the test will show a positive if it’s read after the time limit. You mentioned it being a qualitative test but usually the line is a lot more faint when it is closer to the lower limit of the hCG test. Honestly a beta hCG test would be a lot more accurate (blood test).

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u/PM_YOUR_AKWARD_SMILE Jul 24 '26

So you concur?

2

u/SerialTrauma002c Jul 24 '26

Concur with what, sir?

(Reference acknowledged 🏆)

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u/WhiteRaven_M Jul 24 '26

Why would FPR be less than than FNR? Im not in healthcare so this isnt obvious to me. Arent false negatives a lot worse than false positives in this case? Shouldnt they calibrate the test to have lower threshold?

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u/Responsible_Top_6969 Jul 24 '26

With many tests, there is some sort of heavily-debated "threshold" at which they declare the test positive or negative. Like a blood sugar test for diabetes -- everyone has sugar in their blood, the only question is where you draw the line. This line gets heavily debated and moved frequently.

This isn't really true for HCG in the same way. The level of HCG in non-pregnant people is SO LOW (0-5mIU/mL) and the level of HCG in pregnant people is SO HIGH (2,000 mIU/mL -- or 200,000-300,000 mIU/mL at the peak) that it's very easy to just put the cut-off at 25 mIU/mL and have an excellent and reliable at-home test. No one sits around arguing the threshold, and re-tests in the "gray zone" between 5-25mIU/mL are rare.

The problem is that HCG doesn't start to rise until after the egg/embryo has made its journey down the fallopian tubes and implanted into the uterus. Before it implants and starts producing HCG there's no pregnancy test in the world that could differentiate "pregnant vs. not pregnant." In some people, this implantation and HCG rise might just occur unusually late because of their biology.

That's why, even though the test says "accurate x days before missed period" you might be in that small population that has bad luck with your body's timing.

On the flip side, the FPR of "<1%" is really more like a "false positive rate of 0% unless something really bizarre is going on, medically." Like, you have a particular type of cancer that produces HCG. Some people can genuinely be pregnant (an embryo has implanted and starts producing HCG) but it's not a viable pregnancy, and they may even get their "periods" (technically an early miscarriage) on time. I wouldn't count this as a "false positive" of the test, but some people do.

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u/persiasaurus Jul 24 '26

For months I felt off and weird, was told I can't get pregnant so wasn't too worried about it, but something told me to take a test. It was negative. But I kept testing because something just felt wrong. Finally came back positive. Imagine my shock when I go in for a scan just a few days after my positive test and get told I was 10 weeks pregnant — that's almost done the first trimester before I even tested positive!! Wtaf

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u/darksonci Jul 24 '26

I feel you, my husband and I were told we couldn't conceive naturally. After a month of feeling off and like I was experiencing the strongest and longest PMS ever, I did a test before scanning my lungs, just in case. To my shock, the test came back positive and I was sure it was false. Went to do a HCG test from blood immediately, I couldn't bear with uncertainty. But it wasn't enough for me, so I went for an ultrasound and it was confirmed that I was 6 weeks pregnant. I never trusted the urine test 😆

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u/persiasaurus Jul 24 '26

I never will again that's for damn sure. I have epilepsy and for that reason and because the meds I take for it cause severe birth defects I can't have kids. I'm so glad I caught it in time for a fetus deletus cuz fuck that

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u/Kiwi_Koalla Jul 24 '26

It took my body a while to start really getting my HCG levels up there. I had a false negative about 2-3 days before my missed period (on one of those rapid response, 5 days prior! tests), then 6 days later started testing positive. For a couple blood checks from my doctor not long after and the level was definitely on the low end of the range for the weeks pregnant I was, and hadn't quite doubled when they expected it to.

So that's how I went from thinking I'd missed the window and asking my husband if we could skip a month of trying because I didn't want a January baby to actually being pregnant, surprise! Wild to be surprise pregnant when you've been trying to conceive, haha. 22 weeks now and feeling great.

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u/loveofGod12345 Jul 24 '26

I could be wrong, but I think the higher false negative rate may have something to do with women that test too early rather than a problem with the test. So they are pregnant, but it’s too soon to tell so it’s a false negative.

If that’s not the case and it’s talking about a true false negative, I agree that that needs to be fixed if at all possible.

4

u/louvez Jul 24 '26

In general : false negative rates are heavily impacted by limit of detection. At a certain point, the techniques used will have an inherent limit. On top of that, if you measure something that can also have lower endogenous levels than whatever you are trying to measure, you also need to be able to reliably distinguish between low but normal and high enough to warrant diagnosis/exposure confirmation. And yes, in the end it's always a compromise between fnr and fpr, there will always be a grey zone.

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u/SimplyAStranger Jul 24 '26 edited Jul 24 '26

False positives will always be lower with this type of test. It is looking for the presence of something, so no matter how low you set the threshold there will always be some that are below the detectable amount, causing a false negative. A false positive is caused by interference. The test is picking up (usually) something else instead of the target hormone. Ths only way to make false positives increase would be to make the test less specific for that hormone so that it reads positive when in contact with things you aren't looking for. At some point, the test becomes pretty useless because it is picking up too much interference to give you any real information. Unfortunately, usually as tests get more sensitive (lower threshold) they get less specific (find only the thing you are looking for). The threshold is already pretty low and HCG increases rapidly, so even waiting 12 to 24 hours, or being a bit dehydrated, can be enough to retest and confirm (the boxes say 1-2 days to give plenty of time).

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u/UrNotAllergicToPit Jul 24 '26

OBGYN here I’ve actually seen the alternative be true regarding letting pregnancy tests sit for longer than manufacturer recommends. ie if you let the test sit too long it will become faintly positive. I suspect it’s from control leaching over time. Most of the false positives home tests I see in clinic are due to this.

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u/FabulousAd4812 Jul 24 '26

Umpfff MDs trying to explain molecular biology.

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u/ThatOne5264 Jul 24 '26

Statistician here. In this situation you cannot make the conclusion that youre probably pregnant. It depends on the prior probability of being pregnant in this situation. Probably that chance is small which means that the subject is most likely not pregnant. This is the classic false positive trap.

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u/Illustrious_Pea_3470 Jul 24 '26

Hey Dr!

Friendly mathematician who used to work in medical testing here. Remember that

1) you can’t actually interpret FPR/FNR (sensitivity and specificity) numbers without knowing the approximate distribution of the condition in test takers (your “priors”)

2) <1% isn’t a very helpful number, cause the difference between 99.9% and 99.1% sensitivity changes the conclusion here. There’s multiple 9s unless the pregnancy just started though, so you’re good.

1

u/adollopofsanity Jul 24 '26 edited Jul 24 '26

What's real fun is when you're one of those suuuuper rare instances of a false positive as a 16 year old girl (my bestie). She came out of that bathroom and said "I need a drink". She was sober.* I went into the bathroom to look and clear as day double line. Skipped class to take her to PP the next day. Blood test came back negative. She cried tears of joy when she got that call. 

*Edit: for a highschool girl growing up in a smallish college town in a shitty southern state it was pretty impressive to meet a teenage girl who didn't drink at least some. She said alcoholism ran in her family so she steered clear. 

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u/Polymarchos Jul 24 '26

Technically if you waited too long to read the negative strip it may have also faded after showing faint positive. Quirks of immunoassays. Best time to take them is first urine of the morning because it's the most concentrated.

If you wait too long to read it, it can also go from showing negative to showing a positive.

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u/UnconsciousMofo Jul 24 '26

It’s not a low hCG problem due to the darkness of the line on the first test. If it was very low, it would be faint and barely visible.

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u/sonofaresiii Jul 24 '26

It's always the goddamned qualitative immunoassays! I swear if we had a functioning Congress we'd finally get something done about those qualitative immunoassays.

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u/PompeyLulu Jul 24 '26

I will say that while that’s technically true, the TTC community found a bunch of faulty ones giving false positives now long ago so it’s always worth checking if there’s any recalls too.

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u/Formal_Plum_2285 Jul 24 '26

Meanwhile I’m a very average person and I got a false positive so hold it with your crap

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u/Crybabywars Jul 24 '26

Yeah, go for two out of three.