Chitosans derived from shellfish may spearhead the gel contraceptive revolution Sweden’s Royal Institute has developed a new contraceptive gel with help from the ocean’s creatures. The contraceptive gel is made using chitosans, which are commonly found in the exoskeletons of shrimp, crabs, and lobsters, as well as in the cells of fungi, and unlike mechanical contraceptives such as spermicides, they do not cause vaginal irritation or any damage to the cervix. Scientists are hoping that the gel contraceptive will combine the effectiveness of a hormonal contraceptive with the comfort of a mechanical one to give users the best possible product.
Most contraceptives in the market presently use two ways to prevent pregnancy. One is the mechanical way and the other is hormonal. While hormonal contraceptives work by using a small number of hormones to stop ovulation, by thinning the uterus wall to prevent egg implantation, or by thickening the cervical muscles to prevent sperm from entering. Mechanical contraceptives provide a physical barrier against sperm trying to enter the uterus.
Common hormonal contraceptives include the pill, progesterone implants, hormonal injections, and the patch. Products like condoms, spermicide, and diaphragms are examples of mechanical contraceptives.
Although both these methods help prevent pregnancy with varying efficacy rates, they each have their own set of adverse side effects to take into account. Mechanical contraceptives, may have a higher rate of failure than hormonal contraceptives but hormonal contraceptives can cause many side effects such as headaches, nausea, soreness, or menstrual cycle changes, in fact, they may even increase the risk of strokes and cancer among consumers.
In comparison to this, the contraceptive gel that Dr. Thomas Crouzier, a researcher at Sweden’s Royal Institute of Technology, is developing makes use of the vaginal mucus barrier to prevent conception. The gel his team has developed uses tiny, fibrous compounds called chitosans to create a natural barrier inside the vagina, when the chitosans combine with cervical mucus they form a thick, impervious blockade against sperm.
“By interacting with the cervical mucus gel, the chitosan closes the pores of the gel, and makes it impossible for the sperm to penetrate it,” Crozier said.
To test the efficacy of this gel contraceptive, the team of scientists injected the gel into 8 ovulating sheep. In the experiment, scientists discovered that the gel stopped 98 percent of sperm from making it more than 2 centimeters into the vagina. Only one sheep, sperm was found in the uterus of one sheep after the treatment. Despite making it past the gel barrier the sperm cells were unable to make it to the uterus because the gel gummed up their tails and eventually, the natural acidity of the vagina killed the sperm.
However, this does not mean that the gel contraceptive is without flaws. There is still the need for clinical stage experimentation to establish the safety profile and efficacy in women. It is possible that in actual coital situations, the gel performance of the gel may vary. In addition to this, there are also concerns that the gel may alter the composition of the vaginal microbiome leading to conditions like bacterial vaginosis.
