Depo-Provera, the Depo shot, the birth control shot… these are all names for the same thing: depo-medroxyprogesterone acetate, the injectable contraceptive. Though it’s been around for a long time, “the shot” remains a much less popular option among US women than oral contraceptives and IUDs. According to survey data from the CDC, about 1 in 4 sexually active American women have tried the Depo shot. But in a survey conducted between 2017 and 2019, only about 2.4% of sexually active women reported currently using it. One cause for this disparity may be the FDA’s black box warning against using the shot for more than two years, due to evidence that it significantly reduces bone mineral density (more on this below!).
If you’re considering the birth control shot for contraception or to regulate your menstrual flow, here’s what you need to know.
Depo-Provera is the only birth control shot approved in the U.S.
Depo-Provera (produced by Pfizer) is the brand name of the drug medroxyprogesterone acetate and is the only form of the birth control shot available in the United States. The FDA initially rejected Depo in 1967 due to safety concerns, though it was used in other countries, especially underdeveloped countries with fewer medical safeguards and less access to healthcare. Depo was finally approved in the U.S. in 1992 [1].
As a progestin-only form of birth control, Depo-Provera prevents pregnancy by suppressing ovulation and thickening the cervical mucus to prevent sperm from coming into contact with an egg. It’s recommended as a highly effective form of birth control that eliminates the need to take a daily pill and does not include estrogen, which can cause blood clots and carries concerns for breast cancer.
Depo-Provera is usually given as a shot in the arm or buttock
Users of Depo-Provera must visit a health care provider once every three months to receive an injection. A doctor or nurse administers the shot into a large muscle in the upper arm or buttock. If a user waits more than 13 weeks between appointments, the drug may not effectively prevent pregnancy. She will likely be required to take a pregnancy test before receiving her next shot to ensure that she’s not conceived in the interim, though Depo is not known to affect an existing pregnancy.
A newer version can now be self-administered at home
An at-home version of the shot is also available. Known as Depo-SubQ Provera 104, it still requires a prescription, but it contains a lower dosage and the hormones are injected just under the skin, rather than into a muscle. Nationwide Children’s Hospital provides detailed, illustrated instructions on how to self-administer the shot.
The birth control shot may decrease menstrual cramps and stop all bleeding
According to the Mayo Clinic, the birth control shot may decrease menstrual cramps and pain, lower the risk of endometrial cancer, and lighten bleeding episodes (which are often called “periods,” but are actually not the same thing as your period). About half of women who use the birth control shot eventually stop bleeding altogether [1]. Many sources promote absent periods as an added benefit, ignoring the benefits of ovulation (which always precedes menstruation) for women’s health. What’s more, women tend to be wary when their periods go haywire (or missing altogether), and the number one reason women stop using Depo-Provera is “irregular menstrual patterns” [1].
Weight gain and delayed return of fertility are also common among Depo users
Weight gain is the second most common reason that women discontinue using the birth control shot [2]. Weight gain can lead to insulin resistance, a particular concern for women with polycystic ovary syndrome.
Another cause for concern is the delay in return of fertility after stopping the birth control shot. The Mayo Clinic advises readers that it may take 10 months before your period comes back. Remember that a period follows ovulation. Without ovulation, you cannot conceive. Unfortunately, there appears to be a lack of recent scientific interest in the link between Depo-Provera and delayed return of fertility. The most recent major studies on the topic date back to the 1980s [6].
Brain tumors and breast cancer are also possible
A 2024 French study published in the BMJ found that women who used Depo for longer than one year were at increased risk of developing meningioma, the most common form of brain tumor [7]. While very few Depo users overall developed meningioma (0.05%), this was five times higher than the risk for women who didn’t use progestin-containing birth control (0.01%).
And while the lack of estrogen in Depo (and other forms of progestin-only birth control like O-pill) was hypothesized not to increase breast cancer risk like the pill does, the facts tell a different story. A 2023 study out of Oxford University found that Depo use increased breast cancer risk just as much as the pill, even though it doesn’t contain estrogen [8]. Both combined oral contraceptives and Depo-Provera use increased women’s breast cancer risk by 20-30%. In a May 2024 interview for NPR, Northwestern University professor Dr. Lauren Streicher called Depo “highly problematic”. She noted that it’s no longer prescribed for hormone replacement therapy (HRT) to treat menopausal symptoms, in part because of its connection to breast cancer.
Depo-Provera significantly increases likelihood of contracting or transmitting HIV
Unfortunately, missing periods, weight gain, and delayed return of fertility are far and away the most “innocuous” side effects of Depo. Multiple studies have found that Depo-Provera actually increases the risk of developing and transmitting HIV [2]. This is frequently glossed over by online sources (such as this one for teens) which simply warn that, like all hormonal contraceptives, the shot does not protect against sexually transmitted diseases and recommend condom use for this purpose. But unlike other forms of hormonal contraception, Depo-Provera does raise HIV risk.
A cavalier approach to the Depo-HIV connection is particularly egregious given that Depo is very popular in sub-Saharan Africa, where HIV “has had the greatest impact” [3]. As explained by Dr. Joel Brind in our Depo Safety Watch webinar, Depo can “double—increase by 50 to 100%—the transmissibility of HIV” [4**].
Wait, didn’t the World Health Organization say Depo is safe for all women to use?
It’s true that in 2019 the World Health Organization (WHO) changed their recommendation to say that even women at high-risk of HIV could “use any form of reversible contraception, including progestogen-only injectables [like Depo]”. Natural Womanhood has previously explained the deep flaws in the data analysis the WHO cited to justify changing their stance. Even this 2020 review of literature commented that the change “seems ill-considered and unduly hasty” [5].
A black box warning from the FDA: Depo-Provera spells (bone fracture) disaster for teen girls and young women
The most damning evidence of Depo’s harm to women, and especially to teens and young women, is its detrimental effect on bone mineral density (BMD). In 2004, the FDA added an official black box warning (the most serious level of warning issued by the administration) to the drug’s label: “Women who use Depo-Provera Contraceptive Injection may lose significant bone mineral density. Bone loss is greater with increasing duration of use and may not be completely reversible.”
“Women who use Depo-Provera Contraceptive Injection may lose significant bone mineral density. Bone loss is greater with increasing duration of use and may not be completely reversible.”
Food and Drug Administration
Depo doesn’t just limit bone density growth, it causes bone loss
All hormonal birth control is disruptive to bone growth, which for women is mostly complete by the age of 25. That means the teenage years are crucial for building strong bones and preventing issues like osteoporosis from developing later. The birth control shot stands out from other forms of hormonal birth control in that it doesn’t just limit bone growth. It actually decreases BMD.
Young women are especially vulnerable to Depo’s bone density loss effects
The results of the clinical trials for Depo-Provera illustrate this point well. Adult women in the study suffered significant bone loss. Teenage girls experienced even greater loss over the same period of time, while their untreated counterparts had greater BMD growth than the women in the adult control group. For teenagers who used the Depo shot for more than two years, their bone mass density had not fully recovered five years after they stopped using it.
Even for adolescents who used the Depo shot for less than two years, it took two years after stopping just to return to their baseline bone density. That means, following the FDA-recommended guidelines, girls may lose up to four years of crucial bone development.
Women who previously used Depo are at higher risk of bone fractures
A follow-up study found that women who had previously used the Depo shot were 40% more likely to have had a bone fracture than those who had used other forms of contraception. Keep in mind that these are not older, postmenopausal women suffering osteoporosis. These are young women, still in their childbearing years.
All of the above speaks plainly to the detrimental effects of the birth control shot, especially for young women. Baffling as it is that many sources aimed at young women–and even at teens–continue to promote Depo-Provera, it only underscores the continued need to provide better education for young women about their cycles and overall health.
This article was updated on April 16, 2024, to reflect breast cancer risk with Depo use.
References:
[1] Sharts-Hopko, N C. “Depo-Provera.” MCN. The American journal of maternal child nursing vol. 18,2 (1993): 128. doi:10.1097/00005721-199303000-00015 [2] Carley Tasker, Amy Davidow, Natalie E. Roche, Theresa L. Chang; Depot Medroxyprogesterone Acetate Administration Alters Immune Markers for HIV Preference and Increases Susceptibility of Peripheral CD4+ T Cells to HIV Infection. Immunohorizons 1 November 2017; 1 (9): 223–235. https://doi.org/10.4049/immunohorizons.1700047 [3] Moyo E, Moyo P, Murewanhema G, Mhango M, Chitungo I, Dzinamarira T. Key populations and Sub-Saharan Africa’s HIV response. Front Public Health. 2023 May 16;11:1079990. doi: 10.3389/fpubh.2023.1079990. PMID: 37261232; PMCID: PMC10229049. [4] Brind, Joel et al. “Risk of HIV Infection in Depot-Medroxyprogesterone Acetate (DMPA) Users: A Systematic Review and Meta-analysis.” Issues in law & medicine vol. 30,2 (2015): 129-39. ***Full copy of study available to anyone interested. Comment on this article to request full copy. [5] Hapgood JP. Is the Injectable Contraceptive Depo-Medroxyprogesterone Acetate (DMPA-IM) Associated with an Increased Risk for HIV Acquisition? The Jury Is Still Out. AIDS Res Hum Retroviruses. 2020 May;36(5):357-366. doi: 10.1089/AID.2019.0228. Epub 2020 Jan 22. PMID: 31797677; PMCID: PMC7232639. [6] Fotherby, K, and G Howard. “Return of fertility in women discontinuing injectable contraceptives.” Journal of obstetrics and gynaecology vol. 6 Suppl 2 (1986): S110-5. doi:10.3109/01443618609081724 [7] Roland, Noémie et al. “Use of progestogens and the risk of intracranial meningioma: national case-control study.” BMJ (Clinical research ed.) vol. 384 e078078. 27 Mar. 2024, doi:10.1136/bmj-2023-078078
Hello, i am interested in getting a copy of the study by Joel Brind as mentioned in the references for this article. I learned quite a few things that I had never heard before, especially in the webinar with Dr. Brind, and I am interested in doing a bit more research.