Although birth control pills can affect your breast size, they don’t change breast size permanently.
Before you begin using hormonal birth control, make sure you understand how it can affect your body and what side effects you may experience.
Birth control pills are the most common form of hormonal contraception used in the United States today. They work to prevent unplanned pregnancy in three ways:
- preventing ovulation
- increasing the amount of mucus
- thinning the uterine lining
Each month, your ovaries release a mature egg from your ovaries. This is called ovulation.
If this egg comes into contact with sperm, you could become pregnant. If there’s no egg to fertilize, pregnancy isn’t possible.
The hormones found in birth control pills increase the buildup of sticky mucus on your cervix. This buildup makes it harder for sperm to enter the cervix.
If the sperm are unable to enter the cervix, they can’t fertilize an egg if one is released.
The lining of your uterus is also altered. After a few months of using the pills, your uterine lining may be so thin that a fertilized egg would have difficulty attaching to it. If an egg can’t attach to the uterus, it can’t begin development.
A thinner uterine lining may also affect the bleeding you experience during menstruation. Without a thick uterine lining to shed, your periods may be lighter. Eventually, you may not experience any bleeding at all.
Birth control pills are more than 99 percent effective at preventing unplanned pregnancy if taken properly.
There are some types of birth control that have similar results. These include the ring, the patch, and the shot.
Birth control pills contain hormones. These hormones — estrogen and progestin — are synthetic forms of hormones that naturally occur in your body.
When you begin taking birth control, your levels of these hormones will increase. This shift in hormones can cause side effects. Most of these side effects will ease after a few weeks or months of using the pills.
The hormones in birth control pills may cause changes in your breasts. Only surgery can permanently change breast size, but some women experience changes in breast size when they first begin using birth control pills.
In most cases, any change in breast size is the result of fluid retention or temporary weight gain caused by the increase in hormones.
Some women may experience a change in breast size while taking the active pills in their pill pack. Breast size may return to normal when taking any inactive or placebo pills that may be in your pill pack.
After a few weeks or months on the pill, the temporary changes should subside and your breast size will return to normal.
In addition to changes in breast size, the hormones present in the pill can cause other side effects.
These can include:
- changes in menstrual cycle, such as no bleeding or heavy bleeding
- mood changes
- weight gain
- breast tenderness
The hormones found in birth control pills are synthetic forms of hormones that naturally occur in your body. When taking these pills, the level of hormones in your body increase.
At these increased levels, these hormones can generate changes in your body, such as a temporary increase in breast size or weight gain.
In addition to these changes, some women experience more severe side effects from birth control pills.
These rare side effects can include:
- high blood pressure
- blood clots
- a heart attack
- a stroke
Birth control pills that contain estrogen are more likely to cause these severe side effects.
These side effects are less likely with progestin-only pills. This comes at a trade-off, though. Progestin-only pills are less effective at preventing pregnancy than those containing estrogen.
Most women can successfully take birth control pills without any symptoms, side effects, or complications. However, certain women are advised not to take birth control or to take it with the understanding they may be at higher risk for more severe side effects.
Women who should use additional caution when taking birth control include those who:
- smoke and are over age 35
- have a history of high blood pressure
- have unhealthy levels of cholesterol
- have been diagnosed with clotting disorders
- have a history of migraine with aura
- are overweight or obese and have additional medical issues
Before starting hormonal birth control, you should have a discussion with your doctor about any possible side effects or complications.
If increased breast size is your primary reason for taking birth control, it’s important to remember that most changes in breast size are temporary.
Some woman may not experience a change in breast size when taking birth control. If you’re looking to increase the size of your breasts permanently, discuss your options for breast augmentation with your doctor.
If your goal is to increase the size of your breasts and you don’t want to pursue breast augmentation, you may be interested in chest weightlifting exercises.
These exercises are designed to strengthen the muscles under your breasts, which can give the appearance of larger breasts.
Don’t begin using birth control pills if your primary goal is to enhance your breast size.
Few women experience changes in breast size. Any changes that do occur are often only temporary.
The only permanent way to enhance breast size is through cosmetic surgery.