Sperm-Blocking Gel Emerges Swimmingly As Potential Birth Control Option

You’ve heard of rubbers and The Pill. Soon, the jelly might join the list.

Researchers at KTH Royal Institute of Technology in Sweden have developed a hormone-free vaginal gel that, when applied to the front of the birth canal, can block sperm from reaching the egg. The new contraceptive method has been tested on female sheep to impressive results.

Firstly, we’ll need to address why there should be more birth control alternatives. Condoms, diaphragms, and fertility trackers are some non-hormonal ways people can prevent unwanted pregnancies; unfortunately, they’re not as effective as hormone-based options.

Hormonal methods like the contraceptive pill, on the other hand, are more reliable, though they come with a bevy of side effects like lower libido, mood changes, headaches, nausea, and sore breasts. Still, an estimated 225 million women worldwide use them, according to a study by the United Nations.

With the reversal of Roe v. Wade, women won’t have much sway if they do get pregnant—it doesn’t matter if they tried to prevent this outcome by taking birth control.

The team at KTH is hoping to stave off more accidents with a contraceptive gel designed to be as effective as hormonal birth control—sans the side effects. The researchers have outlined their findings in the Science Translational Medicine journal.

The star ingredient is chitosan, a biopolymer found in fungus and crab shells. When the gel is applied, chitosan combines with the proteins in cervical mucus, thickening the mucus barrier and turning the cervix into a “more selective gatekeeper.”

This keeps sperm from going beyond the cervix and, more importantly, into the fallopian tubes, where the egg is fertilized.

When the gel was applied onto female sheep, which have vaginas similar to a human’s, it created an effective wall, spreading across the vagina and into the front of the cervix. Swimmers went past the cervix of only one sheep in the experiment, amounting to just two out of a billion sperm.

The gel also didn’t cause any inflammation, which may be a side effect of chemical spermicides, another non-hormonal form of contraception.

Thomas Crouzier, a biopolymers researcher at KTH, describes that the gel might hold the key to effectively blocking out sperm without hormones, “since it is reinforcing a barrier that already exists in the women’s reproductive tract.”

Crouzier adds that the gel can be applied in just seconds but potentially have an efficacy that can last for hours, though the effectiveness will “diminish over time as the mucus barrier is replaced naturally.”

Moving forward, the team intends to observe if the gel-enforced barrier remains intact during sexual intercourse of sheep and, ultimately, if it does prevent pregnancies.

Forthcoming human trials will assess how long the gel should be applied before intercourse, as well as how long protection will last.

Crouzier’s company, Cirqle Biomedical, has already inked a US$360 million partnership with women’s health firm Organon to commercialize the gel.

[via New Scientist, EurekAlert, Medical News Today, cover photo 122206343 © Burgstedt | Dreamstime.com]