A Simple Mouth Swab Before IVF is Expected to Increase the Success Rate

Approximately 15 percent of all couples of childbearing age are involuntarily childless. An important reason why so many people rely on artificial insemination is that more and more couples are postponing starting a family. “This is a global trend that is expected to intensify in the coming years. In Europe alone, one million IVF treatments are performed every year, with 25,000 in Sweden,” says Yvonne Lundberg Giwercman, professor at Lund University, who led the study. She has been researching male and female fertility for many years.

The Choice of Hormone Therapy is a Decisive Factor in IVF

In IVF treatment, the woman’s ovaries are stimulated to produce many eggs, which are then removed and fertilized with sperm in a laboratory before being returned to the uterus. There are two different types of hormone treatments available for egg maturation: biological or synthetic. However, strong hormone therapy also carries the risk of serious side effects, which sometimes require intensive treatment – and many IVF attempts fail. In Sweden, the government subsidizes up to three IVF cycles.

“There is an excessive reliance on IVF treatment. Around 75 percent of all attempts fail, and up to 20 percent of women suffer from side effects, some of which are so severe that they require emergency treatment. The choice of hormone therapy is a crucial factor, and a major challenge is that today’s healthcare system has to guess, to a certain extent, which treatment is best for each woman,” says Ida Hjelmér, PhD, laboratory researcher at Lund University and first author of the study.

To find out who responds best to which hormone treatment, the researchers turned to genetics. A total of 1,466 women undergoing IVF treatment at the Reproductive Medicine Center at Skåne University Hospital in Malmö, Sweden, were included in the study. Women with endometriosis or polycystic ovary syndrome (PCOS) were excluded. Of the 1,466 women, 475 were randomly assigned to two different hormone treatments, while the rest served as a control group. A candidate gene involved in fertilization by mediating the action of follicle-stimulating hormone (FSH), which is known to play an important role in egg maturation, was of particular interest and was mapped using gene sequencing. The study found that women with a specific variant of the FSH receptor gene (FSHR), which mediates the action of the hormone, responded best to biological hormone treatment, while others benefited from the synthetic form of the hormone. By knowing a woman’s genetic profile in advance, researchers can increase the number of successful pregnancies.

A Simple Mouth Swab Test Shows Which Hormone Therapy Should be Used

The researchers observed an increase in pregnancy rates and a relative increase of 38% in births among women who received hormone therapy tailored to their gene variation compared to women who did not receive such therapy. This means that for every 1,000 women undergoing IVF treatment, four more school classes are born: 110 more babies. However, gene mapping is expensive and time-consuming. That is why researchers have now developed a simple mouth swab test that shows within an hour which hormone therapy is most suitable.

The result is visible to the naked eye as a pink or yellow coloration. The researchers have applied for a patent for the test, founded the company Dx4Life AB, and are being supported by LU Innovation, LU Ventures, and the SmiLe Incubator with a view to marketing the product. “We hope that this will reduce suffering for women, increase the number of successful treatments, and lower costs for taxpayers. Our goal is to bring the test to market by early 2026,” says Yvonne Lundberg Giwercman, who is also the CEO of the company that developed the mouth swab test.