Around half of the home pregnancy kits available in Australia have been recalled after pregnant women received false negatives.
The Therapeutic Goods Administration (TGA) has examined pregnancy brands and found that five of these self-testing kits failed regulatory testing, while another nine have been taken off the market voluntarily by suppliers.
These Pregnancy Tests Are Giving A False Negative
A family planning clinic raised the alarm after three people received false negatives after using the One Step HCG urine test.
The TGA found that these devices failed to pick up the human chorionic gonadotropin (hCG) hormone, which detects early pregnancies.
“Samples of the remaining 27 devices were acquired and tested for whether they recognised only hCG (not other hormones), how sensitive they were to hCG and if the labelling was correct,” the TGA said in a statement.
“A total of 22 of 27 (81 per cent) test kits sampled passed testing and were shown to work reliably.
“The five devices that failed have been subjected to a range of regulatory actions.”
The TGA reveals they could not test the First Response Digital test, as too many devices malfunctioned.
“One product (First Response Digital from Church and Dwight) could not be tested as too many devices malfunctioned. All affected batches were recalled from pharmacies,” says the TGA.
“An investigation by the sponsor revealed a manufacturing flaw, which was corrected and the corrected devices were found to pass in subsequent testing.”
How Pregnancy Tests Work
Pregnancy tests are designed to tell if urine contains the hCG hormone, reveals the TGA.
“This hormone is produced by cells that will develop into the placenta right after a fertilised egg attaches to the wall of a woman’s uterus.
Raised levels of hCG in the urine usually (but not always as it varies from woman to woman) occur about six days after fertilisation.”
The TGA states that most kits detect the hCG hormone at around 25 mIU/mL at the time of a missed period, but some are able to do so earlier.
“If a woman is pregnant, levels of hCG rise rapidly, doubling every two to three days. The test kits use antibodies and dyes to show pink or blue lines or symbols on a test strip.
“One line is a control to indicate whether the test is valid or not and the other indicates how much hCG is present.”
Digital tests have an electronic reader which has a display to say in words or symbols to reveal whether or not a woman is pregnant.
Consumers and health professionals are encouraged to report problems with medical devices.
The TGA says it cannot give advice about an individual’s medical condition but if you are concerned about the issues with these medical devices you are strongly encouraged to talk with a health professional or your GP.
Meanwhile, here are some articles to help you if you have a positive pregnancy test.