Part 1 was about what the different methods are actually doing. Part 2 is about the questions women ask after that.
Will it make me gain weight? Change my mood? Lower my sex drive? Raise my cancer risk? Make it harder to get pregnant later? And what am I supposed to do with the posts saying the pill drains your nutrients, affects your thyroid or damages your gut, or that the copper IUD is “inflammatory”?
For this one, I finally had the time to go much deeper into the research than I ever could during a clinic day. I did not come away thinking birth control is secretly terrible for every woman, and I did not come away thinking women’s concerns should be dismissed because a study average looked reassuring.
The useful answer is more specific.
Some tradeoffs are well established, some depend heavily on the method, and some are real associations that still do not prove cause.
If I were still in clinic, this is the article I would want to hand you before asking you to choose, so that you understand what you are actually choosing.
Two terms first: a combined method contains estrogen plus a progestin (most pills, the patch and the ring). A progestin-only method has no estrogen (the mini-pill, hormonal IUD, implant and shot).
THE SHORT VERSION
Weight: most combined pills and patches have not shown a large average effect. The shot is different.
Mood: the research conflicts. Some women do notice a change, and the most concerning signals show up in teenagers and in the first months.
Sex drive: combined pills measurably change sex-hormone levels, but that does not reliably predict what happens to desire.
Clots and stroke: this is mainly an estrogen question. Your health history can matter more than the fact that a method is called “birth control.”
Cancer: it goes in both directions. Hormonal methods in general, not only the pill, are linked to a slightly higher chance of a breast cancer diagnosis while you use them and for some years after. The combined pill is also linked to a lower risk of ovarian and endometrial cancer.
Fertility: reversible methods have not been shown to cause lasting infertility. The shot can delay the return of fertility longer than the others.
Online claims: many contain a real piece of biology or a real study.
The important question is whether that concern actually changes your decision.
Will birth control make me gain weight?
The answer: not all birth control has the same weight story.
Current evidence suggests combined pills and patches do not cause a large average weight gain. A major review of trials did not find one. That is an average, so it cannot predict your exact body.
The shot, also called DMPA, is the method I would separate from that reassurance. Well-established: in a large randomized trial, women given the shot gained about 4.5 pounds more over 12 to 18 months than women given the copper IUD.
What changes the decision: if weight is a major concern for you, ask about the specific method, because “Does birth control cause weight gain?” is too broad to answer. And if your body changes in a way that matters to you after starting something, you are allowed to bring that back into the decision.
Can birth control affect my mood?
The answer: possibly, and the research cannot yet tell us who will notice it.
This is one of the least tidy areas of the research. Short clinical trials, mostly of pills in adult women, have not shown an average worsening of depression scores. The researchers rated that evidence as very uncertain, and the trials were short and left out several methods.
Large real-world studies are more mixed. Some find more depression diagnoses or antidepressant use among pill users, and others do not. The most concerning signals show up in younger users.
Because the outcome is serious, you should also know that researchers have looked at self-harm and suicide attempts. A Danish study found more suicide attempts after starting hormonal birth control, most of all in teenagers and in the first months. A Swedish study found more medically treated self-harm or suicide attempts among teenagers using hormonal birth control. In adults, a smaller association appeared in the grouped non-oral progestin-only category, which included hormonal IUDs and implants. A Finnish study found no increase.
These events were uncommon in every group, and this kind of study cannot prove that birth control caused them.
What changes the decision: under CDC guidance, a history of depression does not rule out any method. It is a reason to tell your prescriber and to watch the first few months after starting or switching most closely, in yourself or in your daughter. If your mood clearly changes, treat that as real information and go back to whoever prescribed your birth control. You do not have to push through it.
If you are having thoughts of suicide, call or text 988 in the U.S., any time.
What about sex drive?
The answer: the hormone change is real. The effect on desire is much less predictable.
Well-established: combined pills raise SHBG, a protein that binds sex hormones in your blood, and lower free testosterone, the unbound portion. What is not established is that every woman will have lower desire because of it.
In a placebo-controlled trial, overall sexual function was similar on the pill and on placebo, but desire, arousal and pleasure scores were somewhat lower on the pill. Other studies find lower desire, no change or improvement. That makes sense, because sex drive is not controlled by one hormone. Pregnancy worry, pain, mood, your relationship, sleep and whether the method is helping your symptoms all matter too.
What changes the decision: if sex drive is important to your quality of life and you notice a meaningful change after starting a method, that counts. You do not need a study to prove that your experience happened.
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The risks that can actually change the decision
Estrogen, blood clots and stroke
The answer: estrogen-containing birth control raises clot risk, and for most healthy young women the absolute risk is still low.
This applies to the combined pill, patch and ring, because all three contain estrogen. One useful number: pill labeling estimates roughly 1 to 5 blood clots per 10,000 women per year among women not using a combined pill and roughly 3 to 9 per 10,000 among women using one. That is a real increase and still an uncommon event. It is also lower than the clot risk during pregnancy and the weeks after birth.
What matters most is whether something in your health history raises that risk further. If you have migraine with aura, meaning neurologic symptoms such as flashing lights, blind spots, numbness or speech changes around a migraine, estrogen-containing methods should not be used because of stroke risk.
High blood pressure (even when treated), smoking at age 35 or older, a previous blood clot or known clotting disorder, and the first weeks after giving birth can change the decision too. So can a BMI of 30 or higher if you are considering the patch (Xulane and Twirla labels).
What changes the decision: “Is the pill safe?” is less useful than “Is estrogen a good fit for my health history?” If it is not, there are estrogen-free options.
Cancer is not a one-direction story
The answer: hormonal birth control does not simply “cause cancer” or “prevent cancer.”
Current evidence suggests hormonal birth control is linked to a small increase in breast cancer diagnoses while you are using it or have recently stopped. In most studies the extra risk fades in the years after stopping. How small the increase is depends on your age, because breast cancer is uncommon in younger women. In a large UK analysis, five years of pill use in the late teens was estimated to mean about 1 extra breast cancer per 10,000 women over the 15 years after starting. For use in the late 30s, the estimate was about 27 per 10,000.
The link is not limited to the combined pill. It has also been seen with progestin-only methods, including the hormonal IUD in large studies from Denmark and Sweden, though an older study did not find it. None of these studies can prove the method caused the cancers.
Now the other direction. Well-established: long-term use of the combined pill is linked to a lower risk of ovarian and endometrial cancer, and that protection lasts for decades after stopping.
Longer pill use is also linked to a modest increase in cervical cancer risk that fades after stopping. HPV is the main cause of cervical cancer, which is why routine cervical-cancer screening remains important.
What changes the decision: cancer risk is one of the clearest reasons not to talk about “birth control” as if it had one universal effect. Which cancer, which method, your age, your history and why you are using the method all matter.
Will this make it harder for me to get pregnant later?
The answer: reversible birth-control methods have not been shown to cause lasting infertility.
In a review of studies, most women became pregnant within a year of stopping contraception. What can differ is how quickly fertility returns. For the pill, ring, patch, implant and IUDs, any delay is generally short, and how many years a woman had used birth control made no difference.
The shot stands out again. Its label reports that among women who became pregnant after stopping, half had conceived by about 10 months after their last injection. That timing matters if you know you want pregnancy soon, and the delay has not been shown to be permanent.
Two more things I want women to understand:
AMH (a blood test) and antral follicle count (small follicles counted on ultrasound) are used as markers of ovarian reserve. They are not a direct egg count or a prediction of your exact chance of conceiving naturally. Both can read lower during long-term hormonal birth control use and rise again after stopping. A low AMH on birth control does not mean the medication “used up your eggs.”
No period on a hormonal IUD does not mean your ovaries have shut down. Many users still ovulate.
What changes the decision: if pregnancy in the near future matters to you, ask about return-to-fertility timing before you choose a method. A temporary hormone or bleeding change is not permanent infertility.
Before we get into the claims you keep seeing online
I trained in conventional medicine and went on to practice integrative medicine, and I do not see those as opposing teams. Medicine keeps evolving and new data comes out all the time. I think patients do best when their clinicians keep questioning what we were taught, in any kind of practice, even when that is the harder way to work.
So when clinicians and educators I respect raise concerns about birth control, I want to understand what they are seeing. I want the same from the OB-GYNs and primary care clinicians who prescribe it every day and watch it help their patients. Both perspectives can be informed by real clinical experience and research.
What reaches you online is usually a 60-second podcast clip, an Instagram post or one woman’s personal story. That can raise a very legitimate question. It rarely has room to answer it, and a short office visit often does not either.
That is the gap I want HowToHealth to fill. I read across those perspectives and the research behind them to shape my own view, which is the same thing you are trying to do. All of us can only form an opinion from the information we have.
So bring me the concern, and we can look at what it is based on, what is actually supported, what is still uncertain and, most importantly: does this change the decision for you?
“The pill raises hypothyroidism almost 4x.”
What is real: there is a study behind this claim. A 2021 analysis of U.S. health-survey data found a strong association between reporting more than ten years of pill use and hypothyroidism. It is also well-established that estrogen-containing pills raise thyroid-binding globulin, a protein that carries thyroid hormone in the blood, which can change how some thyroid blood tests look.
Where it goes too far: the survey captured one point in time, so it could not show that the pill came first or caused the thyroid condition. It did not record which pills women had used, and its estimate was very imprecise.
Does it change the decision? I would not use that one study to tell a woman the pill causes hypothyroidism. I would tell someone being treated for a thyroid condition to make sure the person managing it knows when she starts or stops an estrogen-containing pill.
A related claim links MTHFR gene variants, pill-related nutrient depletion and thyroid disease. The gene variants are common, and the extensive research behind this article did not find a study testing that full chain.
“The pill depletes your nutrients.”
What is real: some nutrient blood markers do differ in pill users. Vitamin B6 has the most consistent signal. B12 can read lower without a true deficiency, although a low result still deserves follow-up. The evidence for folate, magnesium, zinc, selenium and CoQ10 is older, smaller or less consistent (one, two, three).
Where it goes too far: a lower blood marker is not automatically a meaningful deficiency. We do not have good evidence for one universal “birth-control depletion syndrome,” or that every woman on the pill needs the same supplement protocol.
Clinical observation: in practice, I cared about nutritional adequacy and sometimes used a multivitamin I had vetted for formulation and quality as a basic safety net when it made sense. I was not telling patients to grab a random multivitamin off the shelf. That is my clinical judgment, not a guideline for every woman on birth control.
Does it change the decision? For me, this is a reason to care about nutrition and to check a suspected deficiency properly. I would not use it alone to tell a woman to avoid the pill.
(Separately, anyone who could become pregnant should get 400 mcg of folic acid a day to reduce the risk of neural-tube defects, whether or not she uses birth control. The prevention evidence is specifically established for folic acid; methylfolate is a separate question that deserves its own article.)
“The pill damages your gut.”
What is real: gut bacteria help process estrogen, so the question is a fair one. Observational studies have also linked pill use with Crohn’s disease, a type of inflammatory bowel disease (one U.S. study, a pooled analysis).
Where it goes too far: direct studies of the gut microbiome, the community of bacteria living in your gut, are limited and mostly reassuring so far. A study of Danish women found no clear difference in gut bacteria between women on the combined pill, women with a hormonal IUD and women using neither. The Crohn’s association deserves more study, but a 2022 review graded that evidence as weak, and it does not prove the pill caused the disease.
Does it change the decision? If you have inflammatory bowel disease or significant gut concerns, bring that history into the conversation. The evidence does not support telling the average woman that the pill damages her gut.
“The copper IUD is inflammatory.”
What is real: this one starts with true biology. Every IUD causes a local inflammatory reaction inside the uterus, copper strengthens it, and that is part of how the copper IUD prevents pregnancy. A randomized study also found changes in vaginal bacteria and local inflammatory markers after copper-IUD placement.
Where it goes too far: local inflammation inside the uterus is not the same as inflammation throughout the body, and whole-body harm has not been shown. Neither has copper toxicity in typical users (one study).
Does it change the decision? The tradeoff I would focus on first is more practical. Copper IUDs can make periods heavier and crampier, especially at first. If your periods are already very heavy or your iron runs low, that may matter far more to your decision than the word “inflammation.”
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Three things I would not want buried in the fine print
1. Your medication list can change the answer
Most common antibiotics do not make birth control fail. Some other medicines do matter, according to CDC guidance and drug labels:
Rifampin and rifabutin (tuberculosis medicines) and several seizure medicines, including carbamazepine, phenytoin, topiramate and oxcarbazepine, can make pills, the patch and the ring less reliable and may affect the implant. IUDs are not affected.
St. John’s wort can make some hormonal methods less reliable too.
Lamotrigine, used for epilepsy and bipolar disorder, runs the other direction. Estrogen-containing pills can lower its levels enough to affect seizure or mood control, and stopping the pill lets them rise again.
Tirzepatide (Mounjaro, Zepbound) has a label warning for birth control pills: switch to a non-oral method or add a barrier method, such as condoms, for four weeks after starting it and after each dose increase.
What changes the decision: bring your real medication and supplement list into the contraception conversation, and tell each prescriber before you start or stop a method.
2. IUDs and implants have practical tradeoffs too
An IUD insertion can hurt. Pain should be discussed and a pain-management plan made around your preferences, so ask about your options before the day of the procedure.
An IUD can also come partly or fully out of place (expulsion). That happened to about 1 in 20 women over five years in a large U.S. study, more often right after delivery and in women with heavy periods. Much more rarely, it can push into or through the wall of the uterus (perforation).
Pregnancy with an IUD is unlikely, but if it happens you need prompt evaluation for an ectopic pregnancy, meaning a pregnancy growing outside the uterus.
With the arm implant, the biggest practical tradeoff is unpredictable bleeding, the most common reason women have it removed.
These things may not sound as dramatic as a viral hormone claim, but they often decide whether a woman is actually happy with her method.
3. The shot deserves its own conversation
My clinical judgment: after reviewing these methods side by side, the shot is the reversible method I would generally be least likely to suggest unless something about a woman’s situation made its advantages the best fit. That is my interpretation of the evidence, not a guideline saying the shot is a bad method.
It is the method where several tradeoffs collect in one place:
The clearest weight-gain signal.
Loss of bone density during use, serious enough to carry an FDA boxed warning. The label advises against more than two years of use unless other options are inadequate, and says the effect on peak bone mass in teens and young adults is unknown. In most studies bone density recovers after stopping, though full recovery after long-term use is less certain.
The longest delay in return to fertility.
A blood-clot signal that the CDC flags separately from other progestin-only methods.
A newer FDA warning about meningioma, a usually noncancerous tumor of the tissue covering the brain and spinal cord, seen mainly with long-term use.
The shot has real advantages too. It contains no estrogen. There is no daily pill to remember, and nothing stays inserted in your uterus or arm. It is private. Some medicines that interfere with the pill are less of a problem with the shot. Periods stop for many users, and one version is FDA-approved for endometriosis pain.
What changes the decision: the useful question is whether the shot’s advantages are worth its particular tradeoffs for you.
So how do you actually choose?
I would not start with “Which birth control is healthiest?” I would start with four questions.
What job do I need this method to do? Prevent pregnancy, make my periods lighter, help pain or acne, or more than one?
Which tradeoffs matter most to me? Avoiding estrogen, avoiding a procedure, predictable bleeding, protecting bone health, wanting pregnancy soon, or not having to remember something every day?
What in my health history changes the answer? Migraine with aura, blood pressure, past blood clots, smoking, heavy periods or low iron, a recent birth, my mental-health history, and every medication and supplement I take.
What would make me reconsider? A meaningful mood change, a change in sex drive, bleeding I cannot live with, weight gain, pain, or simply realizing the method no longer fits what I want.
Every method asks you to accept something, and no method is perfect. The goal is to understand the tradeoffs well enough to choose them on purpose.
If anything here makes you want to stop or switch, line up your next method first. Fertility can return quickly, and pregnancies have occurred within one to two weeks of implant removal.
When to get help
Part 1 has the fuller warning-sign list. Call 911 for sudden trouble breathing, severe chest pain, new weakness on one side, trouble speaking, sudden vision loss or a sudden severe headache unlike your normal headaches. New swelling or pain in one leg needs prompt medical attention.
Call a clinician promptly if you might be pregnant with an IUD in place, have severe pelvic pain after placement or can no longer feel the IUD strings.
If your mood changes seriously, tell someone and contact the person who prescribed your birth control. For thoughts of suicide, call or text 988 in the U.S.
And if a method simply makes you feel worse in a way that matters to you, you are allowed to revisit the decision even when nothing dangerous is happening.
Birth control has a job. I want you to understand exactly what that job is, what it isn’t doing, what the tradeoffs are, and what else deserves attention in your health.
My job here isn’t to convince you to get on it or off it. My job is to make sure you understand enough to make that decision on purpose.
If a podcast clip, a friend or a clinician raises a concern for you, bring that question here. We can take it seriously without automatically being scared of it.
What birth-control question do you still want me to look into next?
Know a woman choosing a method right now, or a mom helping her daughter choose? Send her this.
Congratulations, we’re healthing.
Lindsay Savage, PA-C
The numbers, for anyone who wants them
Most figures are kept out of the article so they do not compete with the answers. Here they are, with their sources.
Weight: in a randomized trial of about 7,800 women in four African countries, the shot group gained about 4.5 pounds more than the copper-IUD group over 12 to 18 months, and the group given a levonorgestrel implant (not the one used in the U.S.) about 2 pounds more. The shot’s label reports average gains of 5.4 pounds at one year and 8.1 at two among women who stayed on it, with no comparison group. Of the 49 pill and patch trials in the review, four used a placebo or no-treatment group, so smaller effects are harder to rule out.
Mood and sex drive: in a placebo-controlled trial of 340 women, those on a combined pill reported lower general well-being than those on placebo, with no significant difference in depression scores, and lower desire, arousal and pleasure scores with similar overall sexual function. Free testosterone fell by about 61% on average across 42 studies of combined pills.
Breast cancer: the UK estimates are 8 extra cases per 100,000 women when the pill was used for five years at ages 16 to 20, and 265 per 100,000 at ages 35 to 39, counted over 15 years (the five years of use plus the ten after).
Ovarian, endometrial and cervical cancer: in pooled analyses from high-income countries, ten years of pill use meant about 80 ovarian cancers per 10,000 women by age 75 instead of 120, and about 130 endometrial cancers instead of 230. With ten years of pill use, cervical cancer by age 50 rose from about 38 to 45 per 10,000 and returned to baseline about ten years after stopping. Ovarian protection has not been clearly shown for progestin-only methods, where data are limited.
Fertility: across 22 studies, about 83% of women were pregnant within 12 months of stopping, with no never-user comparison group. In a study of nearly 18,000 women, the delay was roughly two cycles after an IUD or implant, three after the pill or ring, four after the patch and five to eight after the shot. The shot’s label gives a range of 4 to 31 months to conception. In a study of women 30 to 44 with no history of infertility, low AMH did not predict a lower chance of conceiving.
The “almost 4x” thyroid figure: an odds ratio of 3.8, with a 95% confidence interval running from 1.4 to 10.5.
IUDs: in the U.S. study of more than 300,000 placements, perforation occurred in about 6 per 1,000 women over five years (about 3 per 1,000 among women who had not given birth in the previous year) and expulsion in about 5 per 100.
Implant: about 1 in 9 women in the trials behind its label stopped because of bleeding changes.
The shot and meningioma: in a large U.S. study, the association was concentrated among women with more than four years of use or who started after age 31.
Sources & evidence notes
Sources last checked October 7, 2026.
CDC — Summary chart of U.S. Medical Eligibility Criteria for Contraceptive Use, 2024
Mørch et al. — Breast cancer in users of levonorgestrel-releasing intrauterine systems. JAMA, 2024
Hadizadeh et al. — Hormonal contraceptive formulations and breast cancer risk. JAMA Oncology, 2025
Yland et al. — Pregravid contraceptive use and fecundability: prospective cohort. BMJ, 2020
Depo-Provera CI — prescribing information, revised December 2025
NICE guideline NG239 — Vitamin B12 deficiency in over 16s, recommendation 1.3.8
Fallah et al. — Effect of contraceptive pill on selenium and zinc status. Contraception, 2009
Lamictal (lamotrigine) — prescribing information, revised October 2025
Mounjaro (tirzepatide) — prescribing information, revised August 2026
Zepbound (tirzepatide) — prescribing information, revised August 2026
CDC — U.S. Selected Practice Recommendations, 2024: intrauterine contraception
CDC — U.S. Medical Eligibility Criteria, 2024: progestin-only contraceptives
Iversen et al. — Contemporary hormonal contraception and ovarian cancer: Danish cohort. BMJ, 2018
Evidence notes: Label statements and CDC eligibility categories are well-established. Mood, self-harm, breast cancer, Crohn’s disease and hypothyroidism findings come from observational studies, which show associations and cannot prove cause. Cancer figures are estimates from pooled analyses. Blood-marker changes are kept separate from clinical deficiency. A copper IUD should not be used by anyone with Wilson disease, a rare inherited condition in which copper builds up in the body (label). Lindsay’s clinical observations and her judgment about the shot are her account, not efficacy evidence.
This article is for education, not individualized medical advice. Your clinician can recommend care for your circumstances.