Most side effects of birth control are mild and temporary, resolving on their own within three to five months as your body adjusts to the hormones. But the specific side effects you experience depend heavily on which type of birth control you use, whether it contains estrogen, progestin, both, or no hormones at all. Here’s what to expect across the most common methods.
Common Side Effects During the Adjustment Period
When you first start a hormonal method (the pill, patch, ring, implant, hormonal IUD, or shot), your body needs time to adapt. During the first few months, you may notice nausea, breast tenderness, headaches, bloating, spotting between periods, or mood changes. These are the side effects most people think of, and they’re also the ones most likely to fade.
The American Academy of Family Physicians notes that adverse effects of hormonal contraceptives usually diminish with continued use, and reassurance that symptoms will resolve within three to five months is often the only treatment needed. If a particular side effect is still bothering you after that window, it’s worth discussing a switch to a different formulation or method rather than waiting it out indefinitely.
How Each Method Affects Your Period
One of the most noticeable side effects of any birth control method is the change to your menstrual cycle, and the direction of that change varies widely.
Hormonal IUDs tend to make periods lighter over time. Standard-dose hormonal IUDs are more likely to stop your period altogether, while lower-dose versions typically result in lighter monthly bleeding with less cramping. Many people consider this a benefit rather than a side effect.
Copper IUDs work in the opposite direction. Because they contain no hormones, they don’t suppress your cycle. Instead, periods can become heavier, longer, and crampier, especially during the first few months of use. For most people this settles down, but heavier flow remains common for the life of the device.
The pill, patch, and ring generally make periods shorter and lighter. The shot can cause irregular spotting for the first several months and often stops periods entirely with continued use. The implant is the least predictable: some people get lighter periods, some get irregular spotting, and some stop bleeding altogether.
Mood and Mental Health Effects
The link between hormonal birth control and mood changes is one of the most discussed side effects. Some people notice increased anxiety, irritability, or depressive symptoms after starting a hormonal method. A large Danish study tracked over a million women and found that those using hormonal contraceptives were more likely to be subsequently diagnosed with depression or prescribed antidepressants. The association was strongest in adolescents and in the first six months of use.
That said, many people use hormonal birth control without any mood effects, and some actually feel more emotionally stable when their hormone levels are consistent rather than fluctuating naturally. If you have a history of depression or notice a clear shift in your mood after starting a new method, that’s useful information for choosing the right contraceptive, not a reason to avoid all hormonal options.
Skin Changes: Acne Can Improve or Worsen
Combined birth control methods (those containing both estrogen and progestin) often improve acne. The estrogen component shrinks oil-producing glands in the skin and reduces the amount of oil they produce. It also prompts the liver to make a protein that binds to testosterone in the bloodstream, leaving less of it free to trigger breakouts. Meanwhile, the progestin component blocks the enzyme that converts testosterone into its more potent form.
This skin-clearing effect isn’t instant. Clinical data suggests it takes roughly six months to see meaningful improvement, so patience matters. On the flip side, progestin-only methods (the mini-pill, shot, implant, and hormonal IUD) can sometimes worsen acne, particularly in people who are already prone to breakouts, because they lack the estrogen that counteracts testosterone’s effects on the skin.
Blood Clot Risk With Estrogen Methods
The most serious side effect associated with combined hormonal birth control is an increased risk of blood clots, specifically venous thromboembolism (a clot in a deep vein, usually the leg, that can travel to the lungs). The numbers are worth understanding because they sound alarming in the abstract but are quite small in absolute terms.
Among women not using hormonal birth control and not pregnant, blood clots occur in about 1 to 5 out of every 10,000 women per year. Combined hormonal contraceptives raise that to roughly 3 to 15 per 10,000 women per year. For context, pregnancy itself carries a risk of 5 to 20 per 10,000, and the postpartum period jumps to 40 to 65 per 10,000. So while the pill does increase clot risk, pregnancy carries a higher one.
Not all pills carry the same level of risk. Older formulations containing levonorgestrel are associated with about 8 clot events per 10,000 women per year, while newer formulations with drospirenone come in higher, at 10 to 15 per 10,000. Progestin-only methods (the mini-pill, implant, hormonal IUD, and shot) do not carry this elevated clot risk, making them a standard alternative for people with clot risk factors like smoking, obesity, or a history of migraines with aura.
Bone Density and the Shot
The injectable contraceptive (Depo-Provera) is the only birth control method with a specific concern about bone health. In 2004, the FDA added a black box warning to its labeling stating that prolonged use may result in significant loss of bone mineral density, that the loss increases the longer you use it, and that it may not be completely reversible after stopping.
The warning specifically cautions that use beyond two years should be considered only when other methods are inadequate. This is particularly relevant for adolescents and young adults, who are still building peak bone mass. For people who use the shot short-term or who switch to it temporarily, the bone density concern is less pressing, as much of the loss appears to recover after discontinuation.
Protective Benefits Worth Knowing About
Not all side effects are unwanted. Long-term use of birth control pills is associated with a meaningful reduction in certain cancer risks. Women who have ever used oral contraceptives have a 30% to 50% lower risk of ovarian cancer compared to those who never have. Endometrial cancer risk drops by at least 30%, with greater protection the longer the pills were used. These protective effects persist for years, even decades, after stopping.
Other commonly reported benefits include reduced menstrual cramps, lighter periods, fewer hormonal migraines (in some people), and improvement in endometriosis symptoms. For many users, these positive effects are the primary reason they chose hormonal birth control in the first place.
Fertility After Stopping
A common worry is that birth control will delay your ability to get pregnant after you stop. For most methods, ovulation can return as soon as your next cycle. Some women conceive within the first one to three months of stopping, while others take several months. The pill, patch, ring, implant, and IUDs do not cause lasting fertility delays.
The shot is the exception. Because it’s a long-acting injection designed to suppress ovulation for three months at a time, it can take longer for fertility to return, sometimes up to 10 months after the last injection. This isn’t a permanent effect, but it’s worth factoring in if you’re planning to conceive on a specific timeline.
Warning Signs That Need Immediate Attention
While most side effects are manageable, certain symptoms while on combined birth control require prompt medical evaluation. These include severe abdominal pain with vomiting, chest pain or difficulty breathing, sudden severe headaches with confusion or vision changes, leg pain with swelling or skin color changes, and yellowing of the skin or eyes. These can signal a blood clot, stroke, or liver problem. Persistent severe mood changes and two missed periods (which could indicate pregnancy) also warrant a call to your provider.