Novel Vaginal Gel Prevents Pregnancy On-Demand

A new non-hormonal gel prevents contraception by keeping vaginal pH levels in a range that is inhospitable to sperm.

The new contraceptive, named Phexxi, a product of Evofem Biosciences (San Diego, CA, USA), developed at the University of Illinois in Chicago (UIC, USA), is based on a combination of lactic acid (1.8%), citric acid (1%), and potassium bitartrate (0.4%). Provided in a pre-filled, ready to use applicator, it works by maintaining the vagina's natural acidic pH level, killing male sperm. To maintain long-term efficacy, Phexxi creates a bioadhesive, viscous layer of gel that coats the vaginal and cervical surfaces, which allows it to remain in place and maintain the acidic environment.


To use Phexxi, the pre-filled applicator and plunger rod are removed from the foil pouch. The plunger rod is inserted into the applicator, and pushed until the two connect. The pink protective cap is then removed. In an appropriate position, the pre-filled applicator is inserted into the vagina as far as it will comfortably go, at which point the plunger rod is pushed until it stops; the single-use delivery device is then disposed of. The gel is effective immediately, delivering a dose of contraceptive gel that lasts up to one hour, which is only effective when used before sex.

“There are any women who feel that hormonal, long-acting birth control is not a viable option, and there are women who struggle to access prescription or implanted birth control due to lack of insurance or access to health care,” said UIC professor of pharmacology Donald Waller, PhD, who developed Phexxi in collaboration with Lourens Zaneveld, PhD, of Rush University Medical Center (Chicago, IL, USA). “There is a need for in-the-moment options that give women control, and I think many women will appreciate that such an option does not rely on steroid hormones. My hope is that women feel empowered with options to protect themselves.”

Vaginal pH levels are crucial to maintaining a healthy environment and preventing bacteria growth. Vaginal pH balance is maintained at a homeostasis between 4 and 4.5 due to Lactobacilli, naturally occurring bacteria that produce lactic acid, which helps reduce the reproduction of alkaline bacteria that can cause bacterial and yeast infections. During intercourse, vaginal pH levels may rise to protect the sperm as it travels towards the egg.

Related Links:
Evofem Biosciences
University of Illinois in Chicago