In ye olden days, one had to sacrifice a rabbit and harvest the ovaries to determine a pregnancy. I also read somewhere that cane toads can also be used. In an episode of Degrassi High, Spike buys a drugstore preg test and the results will be known in an hour (I don’t know if this was a pee stick test). These days, a result is known within a couple of minutes on a pee stick test and confirmed with a blood test. Some pee sticks claim to be so sensitive, they can be used up to four days before an expected period.

Is it only the advances in hCG sensitivity that have determined the decreased time in getting an accurate result? And what is the chemical used in pee sticks to detect hCG?

Divine Angel said:

And what is the chemical used in pee sticks to detect hCG?

Methodology
Most tests employ a monoclonal antibody, which is specific to the β-subunit of hCG (β-hCG). This procedure is employed to ensure that tests do not make false positives by confusing hCG with LH and FSH. (The latter two are always present at varying levels in the body, whereas the presence of hCG almost always indicates pregnancy.)
Many hCG immunoassays are based on the sandwich principle, which uses antibodies to hCG labeled with an enzyme or a conventional or luminescent dye. Pregnancy urine dipstick tests are based on the lateral flow technique.
The urine test may be a chromatographic immunoassay or any of several other test formats, home-, physician’s office-, or laboratory-based. Published detection thresholds range from 20 to 100 mIU/ml, depending on the brand of test. Early in pregnancy, more accurate results may be obtained by using the first urine of the morning (when urine is most concentrated). When the urine is dilute (specific gravity less than 1.015), the hCG concentration may not be representative of the blood concentration, and the test may be falsely negative.
The serum test, using 2-4 mL of venous blood, is typically a chemiluminescent or fluorimetric immunoassay that can detect βhCG levels as low as 5 mIU/ml and allows quantification of the βhCG concentration.

https://en.wikipedia.org/wiki/Human_chorionic_gonadotropin

I heard something on the news in the last couple of days about the unreliability – false positives and false negatives – pharmacy pregnancy tests. I’ll have a quick look and see if I can find it.

I remember MASH surgeons used Radar’s rabbit ovaries to see if Hotlips was pregnant

This would be it.

http://www.news.com.au/national/breaking-news/inaccurate-pregnancy-kits-off-shop-shelves/news-story/a353fcfe3220aa99c590841bad7ccdc7

buffy said:

I heard something on the news in the last couple of days about the unreliability – false positives and false negatives – pharmacy pregnancy tests. I’ll have a quick look and see if I can find it.

Poik tells them anything.

Rabbits were (almost) never used: mice were used because they were (are) a lot cheaper.

is DA preggers again?

Arts said:

is DA preggers again?

i don’t know. Will this be in the test?

The downside of pregnancy tests.

A fungus that grows on the backs of frogs may be responsible for the extinction of dozens of species, say the authors of a study published in Thursday’s issue of Nature. Amphibian chytrid fungus seems to have spread around the world astride the South African clawed frog, Xenopus laevis, which was exported for use as a pregnancy test. Wait a second—how do you use a frog to test for a baby?

You inject some urine into its dorsal lymph sac in the morning and check back at the end of the day. A dose of a pregnant woman’s pee will cause a female South African clawed frog to lay eggs within eight to 12 hours. The test also works on male frogs, which produce sperm in response to the injection.

The frog test works because a pregnant woman’s urine contains a hormone called human chorionic gonadotropin, or hCG. Most modern pregnancy tests rely on the detection of hCG using other means: The standard home test kit, for example, flags hCG with prepared antibodies. But until the 1960s, the best way to detect the hormone was to inject urine into an animal and wait to see what happened.

Arts said:

is DA preggers again?

No, just a curious mind triggered by an episode of Degrassi.

Divine Angel said:

Arts said:

is DA preggers again?

No, just a curious mind triggered by an episode of Degrassi.

What is this 1987?

Witty Rejoinder said:

Divine Angel said:

Arts said:

is DA preggers again?

No, just a curious mind triggered by an episode of Degrassi.

What is this 1987?

Yep. Mini Me was pulling out DVDs and I watched a couple of eps while she was napping, just to see how badly it’s aged.