Certain types of birth control methods have been associated with reduced bone mineral density. The risk may be greater in people who start taking them during adolescence.

Birth control medications work to prevent pregnancy, with oral contraceptives considered safe for most people depending on health history and individual risks.

However, one possible risk of oral contraceptives and other types of hormonal-based birth control methods is bone loss. It’s thought this may occur from a reduced bone mineral density (BMD).

If you’re currently taking or about to start birth control, consider speaking with a healthcare professional about the possible risks of decreased BMD.

While researchers are still looking at the links between birth control and bone loss, it’s thought that the use of synthetic hormones may play a role.

A 2021 review found that estrogen in birth control could increase the risk of bone loss at any amount, including low dose medications.

They also found that adolescents may be particularly vulnerable to these effects. This is of particular concern, given that females achieve about 95% of their adult bone mass by the age of 17 years. The authors noted that various factors, such as diet and calcium intake, could also influence BMD.

Adults older than 30 years experience natural decreases in bone mass as they age. However, the concern is that taking birth control could accelerate this process or reduce fully developed bones by early adulthood.

As such, researchers are still trying to understand how birth control might increase the risk of osteopenia (decreased BMD) and, eventually, osteoporosis (weak and thinning bones).

Not everyone who takes birth control will experience bone loss.

For some groups, such as people experiencing menopause, estrogen-containing birth control may decrease fracture risk and promote bone health.

More research is necessary to understand why some people are more at risk for decreased BMD than others when taking these medications.

Hormonal birth control methods are thought to cause bone loss, especially those containing estrogen. However, not all types of birth control have the same effects on bones.

Much of the focus between birth control use and bone loss has been focused on oral contraceptives, as these are the most commonly prescribed methods of hormonal birth control.

To date, research suggests that estrogen-containing birth control pills may decrease BMD. However, progestin-only birth control pills have not been found to affect bone density, according to a 2020 review.

Aside from oral contraceptives, birth control shots are also known to pose problems to bone health. Such is the case with medroxyprogesterone (Depo-Provera) injections, especially when used during adolescence or early adulthood.

Experts believe these shots may increase the risk of osteoporosis and bone fracturs later in life. For these reasons, Depo-Provera is recommended for short-term use only of up to 2 years.

On the flipside, intrauterine devices (IUDs) are not associated with bone loss, per current research. Both IUDs and Depo-Provera shots don’t contain estrogen. More research is necessary to uncover why certain types of progestin may influence bone loss like estrogen might.

A doctor may recommend calcium or vitamin D supplements, as well as regular weight-bearing exercises to help support BMD and prevent bone loss.

If your t-score (bone density measurement) is between negative 1 and 2.5, a doctor may recommend medications to prevent further bone loss. Some of these options may include:

Adolescents who take birth control may also be at risk of experiencing osteopenia or osteoporosis earlier in life. This age group may also have a higher risk of bone fractures in early adulthood because of an underdeveloped bone mass.

In general, osteopenia and osteoporosis may both increase the risk of fractures regardless of age.

With osteoporosis, the bones may become so weak and fragile, that everyday movements could lead to fractures.These include minor falls, bending over, or lifting small objects.

Consider speaking with a doctor if you have concerns about your bone health or if you’re taking or considering starting birth control. They can help you determine whether certain methods are appropriate and possibly recommend other treatments when necessary.

It’s also important to know that birth control is not the only type of medication that may increase the risk of bone loss. The following types of medications have also been linked with osteoporosis when used long-term:

Does birth control affect your bones?

Certain types of birth control, such as estrogen-containing birth control pills and the Depo-Provera shot, may pose the risk of bone loss in some people.

Which hormone causes bone loss?

Estrogen is a hormone responsible for maintaining our bone structure. An estrogen deficiency can increase your chances of bone loss.

Can birth control affect your legs?

Yes, birth control can affect your legs in several ways, such as causing swelling and pain and increasing your chance of blood clots.

Certain types of birth control may pose the risk of bone loss in some people.

These include estrogen-containing birth control pills, as well as the Depo-Provera shot. The risk also appears to be greatest in adolescents and teens who take them before full bone development.

Consider speaking with a doctor about the possible risks of birth control and alternative options that may be better suited.

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