There are several at-home blood based medical tests on the market, including one for HIV and another for cholesterol. Why hasn’t a blood-based HPT been marketed yet? Obstensibly they’d be more sensitive, and detect pregnancy earlier and more reliably than urine based ones, especially since blood has less of a dilution issue. This would relieve stress for couples, especially ones with fertility issues. Moreover, they’d permit earlier prenatal care or pregnancy termination, which would be a boon medically in either scenario. With fertility products being such a large market right now, why haven’t we seen the avent of blood-based HPTs?
I’m thinking that there is no real factual answer for this.
My opinion. It ain’t no fun poking yourself to get blood.
I know, I do it every day.
Urine works fine. Why risk infection?
Urine is subject to dilution problems, and a longer length of time to build up the needed level of HCG.
I don’t think infection is much of an issue for non-immno compromised individuals. Diabetics obviously are more at risk with the healing issues associated with the condition. But gen pop using a sterile lancet, I doubt there’d be much risk.
Urine tests are painless, cheaper and really quite accurate. Blood tests are more expensive, only marginally more accurate, and invite complications like infection, hematomas, bruising, etc. The advantage of blood testing in the hospital is that the pregancy can be dated to some degree with a “quantitative” BhcG – which most folks with a positive urine go on to get anyway.
Right. But I was thinking like, say, a finger-prick home blood draw- not a 16ga needle and tube draw. We already have many similar tests out there- blood sugar, cholesterol, HIV, etc, so I have trouble imagining this is really too much of a barrier, if one at all.
Plus, it’d let you know earlier, instead of waiting a bagillion weeks and having to pee in your husband’s little OJ glass on the sly.
Seriously, though, I think this is a way under-tapped market. Women, especially those I’ve seen who are desperately hoping for a baby, can get quite neurotic about these things.
When my wife first tested positive on her home pregnancy test, she called the OP/GYN and asked if she could come in and take a pregnancy test to be sure. The doctor called back and asked “Which home pregnancy test did you take?”. My wife replied and the OB/GYN said “Well, there you go. They are about as accurate as any one we can give you. Congratulations!. Let’s schedule your first appointment.”
I believe that you hit against the law of diminishing returns with other tests.
My impression was that at home HIV tests require you to collect the blood and send it elsewhere for analysis. The advantage being anonymity - but that they weren’t any faster, since it would be necessary to wait for it to be mailed.
The blood test is not dramatically more accurate than the urine test, and you would get the result at most one day later. Most people don’t like getting poked with needles. Cholesterol and blood sugar tests need to be quantitative (give you a number, not just a “yes” or “no”). If sugars and cholesterol could be done using urine, millions of diabetics would breathe a sigh of relief. And lots of people get pain and infection from needles even when not immunosuppressed.
People get neurotic about pregnancy, and you could spin it into a product. But your product would be worse, not better, than what exists (regardless of what you personally believe). You would likely get similar accuracy by using a sample of blood in the same test used for the urines!
IIRC the most sensitive blood tests can detect BHCG 7 days after conception, while the most sensitive urine tests detect BHCG 10-14 days after conception.
Studies that have been done using the most sensitive tests suggest that a fairly significant number of pregnancies (10-15%) diagnosed prior to, or at implantation aren’t actually viable and will miscarry at the time the woman would normally have had her period. That’s not counting the 20-30% of diagnosed pregnancies that will miscarry after 4 weeks.
So you’d find out a week earlier, but that extra few days confers no real advantage. Waiting and taking a test on the day your period was due, if it doesn’t arrive is more rational. Not only will the BHCG levels be high enough to get a more accurate result, but you already know that implantation was successful.
The exceptions are specific situations such as suspected ectopic pregnancy or IVF, where knowing what you’re dealing with very early on can be helpful.
1 week will make absolutely no difference to the vast majority of pregnancies, and for some women, the knowledge that they had a very early miscarriage will be more emotionally hurtful than not knowing.
Many women don’t realise they are pregnant until 2,3 or more months have passed, and this usually has no impact on the outcome, so a week’s difference early on isn’t vital.