The copper IUD is often presented as THE hormone-free contraceptive solution. 99% effective, put it in and forget it for 5 to 10 years, no forgetting possible. On paper, it's perfect. In reality, it's more nuanced. Some women love it and would never go back to the pill. Others remove it after a few months, exhausted by heavy periods or PMS they no longer recognize. In between, many fumble, adapt, and hesitate. This article isn't going to tell you whether the copper IUD is great or horrible. It will present the scientific facts, the documented side effects (and those less talked about), and above all, real testimonials so you can make an informed choice.
The main thing to remember
- Menstrual flow increases by 50-55% on average the first 12 months (scientifically measured)
- 10 to 20% of users develop iron deficiency, 10% clinical anemia
- Menstrual pain increases in 38% of women in the first 3 months
- Most side effects improve after 6 months, but not for everyone
- The link between copper IUD and Severe PMS/depression remains controversial (lots of evidence, little proof)
- The copper IUD does not make you fat (no hormones), but water retention is possible
- Efficiency: 99,2-99,6%, comparable to hormonal IUDs
How Does the Copper IUD Work?
Before discussing side effects, it's important to understand how the copper IUD works. Contrary to popular belief, it's not just a "mechanical barrier."
The Triple Mechanism of Action
1. Spermicidal action of copper
Copper ions released in the uterus are toxic to sperm. They destroy their cell membrane and impair their mobility, preventing them from reaching the egg.
2. Chronic inflammatory reaction of the endometrium
The body reacts to the IUD as if it were a foreign body. It creates a permanent local inflammation of the uterine lining that prevents the implantation of a potential fertilized egg. It is this inflammation that explains many of the side effects.
3. Changes in cervical mucus
Copper slightly thickens cervical mucus, making it more difficult for sperm to pass through.
This chronic inflammation is precisely what makes the copper IUD so effective, but it is also what causes the majority of adverse effects.
Scientifically Documented Side Effects
Clinical studies have objectively measured the effects of the copper IUD on thousands of women. This data does not lie.
Heavier Periods: Side Effect #1
This is the most common and best-documented side effect. Studies using the alkaline hematin method (an objective measure of blood loss) have shown precise figures.
The real figures
- Average increase: 50-55% the volume of blood lost during menstruation in the first year
- Before IUD: average flow of 59 ml per cycle
- After IUD: average flow of 91 ml per cycle (i.e. 32 ml more)
- The rules also last 1 to 2 more days than before
- Around 60% of women report heavier periods than on the pill
Why this increase? Copper-induced inflammation increases the production of prostaglandins in the uterus. These molecules cause more intense contractions and greater shedding of the endometrium, resulting in heavier bleeding.
Anemia and Iron Deficiency: A Real Risk
Increased menstrual flow has a direct impact on iron stores. Studies are unanimous on this point.
⚠️ Symptoms of anemia to watch out for
- Chronic fatigue, exhaustion even after a night's sleep
- Shortness of breath on exertion, palpitations
- Paleness of the skin, lips, nails
- Frequent headaches, dizziness
- Brittle nails, hair loss
- Muscle weakness, leg cramps
If you have these symptoms with a copper IUD, ask for a blood test (hemoglobin + ferritin).
Increased Menstrual Pain
Menstrual cramps are the second most common side effect. A study of nearly 2000 women found that 38% reported more menstrual pain with the IUD than before.
Evolution over time
- Months 1-3: 38% report more pain
- Months 4-6: 25% report more pain
- Months 7-12: 15-20% still report increased pain
- The good news: for the majority, it gets better over time.
The pain is caused by the increase in prostaglandins which cause stronger uterine contractions to expel a heavier flow.
Spotting and Intermenstrual Bleeding
About 30 to 40% of copper IUD users experience light spotting between periods for the first 3 to 6 months. This spotting is usually light (a few drops) and gradually decreases.
The Hidden Side: The Lesser-Talked-about Effects
Beyond the "official" side effects, many women report symptoms that are not always listed in the package inserts. These effects are less scientifically documented, but the reports are too numerous to ignore.
Severe PMS and Mood Swings
This is the most controversial side effect, yet one of the most reported on forums. Hundreds of reports describe premenstrual syndrome that became unbearable after the copper IUD was inserted.
What women say
- Extreme irritability the week before menstruation
- Crying spells for no apparent reason
- Questioning their relationship, their work, their life choices every month
- Feeling of mental fog, difficulty concentrating
- Increased anxiety, sometimes cyclical depressive states
- Feeling of "no longer recognizing oneself" emotionally
What does science say? Very few studies have explored this link. One hypothesis raised by some researchers is that chronic inflammation could disrupt the production of neurotransmitters like serotonin. Copper could also interfere with the absorption of zinc and magnesium, two minerals essential for regulating mood and PMS.
Important point
It's impossible to know in advance if you'll experience this effect. Some women experience no mood swings, while others experience emotional hell. If you already had severe PMS before the IUD, your risk is likely higher.
The Copper and Zinc Controversy
Some natural health practitioners and naturopaths suggest that the copper IUD causes copper overload and zinc depletion in the body. This hypothesis is debated in the medical community.
What studies show about blood copper levels
- An Iranian study (2013): slight increase in serum copper after 3 months, but below toxic thresholds
- A Mexican study (2005): blood copper levels significantly higher in IUD users
- Other studies (8 of 12) found no significant increase
- No study measured free copper (the toxic form) but only total copper
Current scientific conclusion: The data are conflicting and the clinical significance remains unclear. The measured copper levels are never toxic, but this does not mean that there are no effects on the body.
The copper/zinc imbalance hypothesis: Copper and zinc are antagonistic minerals. When one increases, the other decreases. Zinc is essential for the production of serotonin (the happy hormone), stress management, immune function, and skin health. A zinc deficiency may explain some of the symptoms reported: fatigue, severe PMS, acne, hair loss, and depression.
However, this theory still lacks solid evidence. Future studies will need to measure free copper, serum zinc, and most importantly, establish a causal link between these measurements and reported symptoms.
Other Reported Effects
- Bloating and water retention: Copper increases sodium retention, which can cause abdominal bloating
- Acne: Some women find their acne returns or worsens after stopping the pill and having the IUD inserted.
- Decreased libido: Rare, but reported by some users (potentially related to fatigue or pain)
- Bowel problems: Some reports mention bloating, constipation or diarrhea
- Recurrent urinary or vaginal infections: Copper can disrupt the vaginal microbiome and promote imbalances
Heavy periods with your copper IUD?
Period Panties are perfect for managing heavier flows. Absorbency equivalent to 3-4 tampons, comfortable and eco-friendly.
Real Testimonies: The Best and the Worst
Experiences with the copper IUD vary greatly from woman to woman. We've compiled real testimonials from French forums to give you an honest look.
Positive Testimonials
Emma, 28 years old: "Already 3 months with the IUD and I think it's great! I've only found positive points: no more forgetting the pill, my periods haven't changed too much but above all... my libido has increased. Since I've been off hormones it's WOW! Well I've got the stomach ache again on the first day of my period that I used to have before being on the pill, but I don't care compared to all the benefits."
Lucie, 34 years old: "I've had a copper IUD for years (renewed when necessary) and it suits me perfectly. No change in flow, nor any particular pain (except 2-3 days after insertion, but moderate). I realized how much the pill changed my libido. Never again hormones for me."
Sophie, 31 years old: "A month already and no side effects! The insertion hurt a lot, but the pain went away after an hour. My boyfriend feels nothing, and I have no more hormones... great! And above all, no more stress, no more fear of bad contraception."
Negative Testimonials
Amélie, 26 years old: "It's been almost 3 years and my PMS is only getting worse. I no longer recognize myself in terms of morale and mood. I literally question my entire life every month around the time of my period: relationship, work, life choices... It's very hard for me and my partner because at the time it's impossible to dissociate the syndrome and moods from what we really think. I'm finally going to get rid of it in a month."
Mathilde, 29 years old: "The only downside is that my periods last between 7 and 9 days and are very heavy. It's really torrential the first two days. I had blood tests: I'm borderline anemic. My doctor prescribed iron, but it constipates me. I don't know what else to do."
Claire, 32 years old: "After almost 10 years of using a copper IUD, I'm thrilled and relieved to have it removed two months ago. I feel good about myself again. My stomach is less bloated, my mood is smoother, and my PMS is less severe. I never made the connection before."
Julie, 27 years old: "I've had a copper IUD for over a year now, and for the past six months I've been extremely tired, in a fog, with brittle nails and extreme hair loss. My doctor did some tests: ferritin at 8 (normal > 15). Severe anemia. He advised me to remove it."
Mixed Testimonials
Sarah, 30 years old: "I'm holding on because I've read that it often takes 3 to 4 months for everything to stabilize. And above all, I want to use contraception without hormones. But the pain on the 3rd day of my period is almost unbearable. Having had 3 children, it feels like contractions to me."
Léa, 25 years old: "Obviously, my periods are heavier in the first few months. But since then, I've gotten back to the same level of flow I had when I wasn't using contraception. I don't have any more pain than before. The only downsides: my period lasts 7 long days and I have quite difficult premenstrual syndrome (irritability, negative thoughts)."
Who Should Avoid the Copper IUD?
Certain situations make the copper IUD inadvisable or even contraindicated.
Absolute contraindications
- Wilson's disease: Genetic disorder that prevents the liver from eliminating copper
- Copper allergy: Rare but possible (causes severe inflammation)
- Current pelvic infection (salpingitis, endometritis)
- Cervical or uterine cancer
- Uterine malformations preventing correct installation
- Unexplained vaginal bleeding
Situations with increased risk of side effects
- Already heavy periods : The IUD will make them even more abundant
- Pre-existing anemia : Risk of significant worsening
- Severe dysmenorrhea : The pain will probably increase
- Uterine fibroids : May cause expulsion and increased bleeding
- Endometriosis : Inflammation of the IUD can worsen symptoms
- PMS already intense : Risk that the IUD will amplify it
Solutions for Managing Side Effects
If you experience side effects with your copper IUD, there are several options before considering removal.
For Heavy Periods
- Non-steroidal anti-inflammatory drugs (NSAIDs): Ibuprofen (400-600 mg) or naproxen during menstruation. Reduces flow by 20-30% and relieves pain.
- Tranexamic acid (Exacyl): Antifibrinolytic that reduces bleeding by 40-50%. Prescription only.
- Period Panties or adapted cups to manage abundance
- Iron supplementation: Iron bisglycinate (better tolerated) + vitamin C for absorption
For Anemia and Fatigue
- Blood test: Hemoglobin + ferritin to confirm anemia
- Iron supplementation: Iron bisglycinate 30-50 mg/day in the morning on an empty stomach with orange juice
- Diet rich in iron: Red meat, liver, lentils, spinach, pumpkin seeds
- Vitamin B12 and folates: If severe anemia
For PMS and Mood Swings
Nutritional approach (copper/zinc imbalance hypothesis)
- Zinc: 15-30 mg/day (red meat, oysters, pumpkin seeds, or supplement)
- Magnesium: 300-400 mg/day (reduces PMS, improves mood)
- Vitamin B6: 50-100 mg/day (serotonin production)
- Omega-3: Natural anti-inflammatories
- Avoid dietary copper (chocolate, seafood, mushrooms) if you suspect an overload
Note: These recommendations are based on the unproven hypothesis of copper/zinc imbalance. Consult a healthcare professional before supplementing.
Does the Copper IUD Make You Fat?
This is a common question. The scientific answer is clear.
No, the copper IUD does not make you gain weight.
The copper IUD does not contain any hormones, so it cannot cause hormone-related weight gain like the pill or hormonal IUD.
However, Copper increases sodium retention, which can cause bloating and temporary water retention (1-2 kg), especially during the premenstrual period. Some women also report weight gain after stopping the pill (independent of the IUD), due to the return of the natural cycle and normal appetite.
Can You Get Pregnant With a Copper IUD?
The copper IUD has an effectiveness rate of 99,2 to 99,6%, or 0,6 to 0,8% failure rate per year. It is one of the most reliable contraceptives, but there is no such thing as zero risk.
If a pregnancy occurs under a copper IUD, there is a 15 to 50% risk of it being ectopic (compared to 2% normally). Check out our full article on pregnancy with an IUD to learn more.
Should You Remove Your Copper IUD?
There is no one-size-fits-all answer. Each woman must weigh the pros and cons based on her situation.
Consider withdrawal
- Severe anemia despite iron supplementation
- Periods so heavy they impact your quality of life
- Unbearable menstrual pain beyond 6 months
- PMS becomes unmanageable, impacts your mental health
- Chronic fatigue that does not improve
- You just don't feel good about it
Keep it
- Side effects are mild and manageable
- You are in the first 6 months and it is gradually improving
- You would rather manage heavier periods than go back on hormones
- The benefits (libido, no hormones, effectiveness) outweigh the drawbacks
- You feel generally good with it
The Copper IUD: A Personal Choice
The copper IUD is an effective, hormone-free form of contraception that works well for some women and much less so for others. Scientifically documented side effects (heavy periods, pain, anemia) are real and common, but they often improve over time. More controversial effects (intense PMS, mood swings, fatigue) are overwhelmingly reported by users, even though science is still struggling to explain them.
No gynecologist can predict how your body will react. Some women go through the adjustment period without any problems and happily keep their IUD in place for years. Others develop debilitating symptoms that warrant rapid removal. Both experiences are valid. Listen to your body, give yourself 6 months to adjust if possible, but don't hesitate to remove the IUD if you really don't feel comfortable with it. Your physical and mental well-being comes before any contraceptive dogma.
Sources & Scientific References
This article is based on scientific studies published on PubMed and real testimonies collected on French forums.
Studies on the side effects of the copper IUD
- Hubacher D, et al. (2009). Side effects from the copper IUD: do they decrease over time? Contraception. PMC2702765
- Goh TH, Hariharan M. (1980). A longitudinal study of serum iron indices and haemoglobin concentration following copper-IUD insertion. Contraception. PMID: 7449387
- Jain K, et al. (2012). Hemoglobin and serum ferritin levels in women using copper-releasing or levonorgestrel-releasing intrauterine devices. Contraception. DOI: 10.1016/j.contraception.2012.08.025
- Milsom I, et al. (1995). The influence of the Gyne-T 380S IUD on menstrual blood loss and iron status. Contraception. PMID: 7554976
Studies on copper and zinc
- Imani S, et al. (2013). Changes in copper and zinc serum levels in women wearing a copper TCu-380A intrauterine device. European Journal of Contraception and Reproductive Health Care. PMID: 24304153
- Crandell L, Mohler N. (2021). A Literature Review of the Effects of Copper Intrauterine Devices on Blood Copper Levels in Humans. Nursing for Women's Health. DOI: 10.1016/j.nwh.2020.11.003
- Prema K, et al. (1980). Serum copper in long-term users of copper intrauterine devices. Fertility and Sterility. PMID: 620840
Studies on the treatment of bleeding
- Grimes DA, et al. (2012). Treatment of bleeding irregularities in women with copper-containing IUDs: a systematic review. Contraception. DOI: 10.1016/S0010-7824(12)00816-5
Sources of testimonies: WeMoms forums, Vivelesrondes, personal user blogs, FRC (French-speaking Consumer Federation) survey.
Medical Warning: This article is for informational purposes only and is not a substitute for professional medical advice. If you experience significant side effects, anemia, or any concerning symptoms, consult a gynecologist, midwife, or your primary care physician.
