Since the debut of the first birth control pill more than 60 years ago, contraceptive methods have remained an area of innovation. Women even a decade ago might have never imagined relying on their phones to prevent pregnancy; but today, hundreds of women use fertility-awareness based apps as an adjunct to birth control.
Two male contraceptive methods and a once-a-month birth control pill for women are currently in clinical trials. Meanwhile, researchers and manufacturers have launched a vaginal ring that aims to be effective for one year and are continuing to refine intrauterine devices.
Here, we review new contraceptive developments from 2020 and beyond.
Once-A-Month Birth Control Pill
A research team at the Massachusetts Institute of Technology has developed an oral contraceptive that releases levonorgestrel slowly into the stomach. They aim to develop a pill that patients can take once a month: The micropill consists of a star-shaped device inside a dissolvable capsule to make it easy to swallow. A 2019 trial in a pig model published in Science Translational Medicine found the slow-release technology was as effective as a daily pill at maintaining a sufficient level of hormone in the blood. Clinical trials are underway.
According to research published in the New England Journal of Medicine, IUDs outperform birth control pills, vaginal rings and patches in preventing pregnancy. One of the latest hormonal IUDs on the market is Skyla, a smaller, low-dose version of the Mirena IUD. Both of these T-shaped devices work by gradually releasing levonorgestrel — 52 milligrams with Mirena and 13.5 milligrams with Skyla. Mirena is effective for five years, while Skyla works for three.
The Mirena implant is 32 millimeters across, which generally restricts its use to women who have given birth. Skyla, however, is just 28 millimeters across and comes with no such limitations.
Some providers may find Skyla easier to place because of its more compact size. Once the IUD is inserted, ultrasound is the best tool to use to confirm the device is correctly positioned. Ultrasound can also help you identify whether an IUD is dislodged or responsible for pelvic pain.
Long-Lasting Vaginal Ring
Annovera, a long-lasting vaginal ring that was approved by the U.S. Food and Drug Administration (FDA) in 2018, is now commercially available. The ring is effective for up to one year but requires removal for one week each month.
Annovera is made of body-safe silicone and releases progestin and ethinyl estradiol. Two clinical trials of the device found 2.98 pregnancies per 100 women in a year of usage among women up to age 35, according to results published in The Lancet Global Health. Patients who use a new NuvaRing every month might appreciate how Annovera saves them repeated trips to the pharmacy for refills.
Expanded Use of Internal Condoms
Internal or "female" condoms are now being marketed in the United States after gaining FDA approval. Unlike more common external or "male" condoms, internal condoms can be worn up to eight hours before use, according to the U.S. Department of Health and Human Services.
This option prevents sexually transmitted infections if used correctly, but it tends to be less effective than external condoms at stopping pregnancy. According to Michigan Medicine, estimated rates of pregnancy with a year of perfect use and typical use are 5 percent and 21 percent, respectively.
Fertility app birth control tools on smartphones rely on algorithms for fertility tracking to avoid pregnancy, analyzing inputted fertility signs over time and then alerting users to avoid intercourse on their peak fertility days. Nearly 100 apps allow women to track their menstrual cycle and fertility, but most are not backed by evidence-based fertility-awareness methods, and few provide disclaimers informing users that the apps are not birth control in and of themselves.
The Natural Cycles app is the first FDA-approved app-based contraceptive method. A postmarket study of 16,331 Natural Cycles users published in BMJ Open suggests the app was most effective at preventing pregnancy among women who had previously used condoms and least effective among women who had switched from oral contraceptives. The researchers suggest that previous contraceptive habits influence Natural Cycles' efficacy in this way because patients are required to remember to use condoms or abstain on days the app indicates are "red," or highly fertile, to prevent pregnancy.
Meanwhile, more developments are on the horizon — chiefly male contraception. A male contraceptive pill cleared a human safety test, according to the Endocrine Society, but developers do not expect it to be commercially available for a decade. Separately, a clinical trial of male contraceptive gel funded by the National Institutes of Health is set to wrap up in 2021.