Copper side effects: what 42,854 FDA adverse event reports show
Drug class
Copper-containing Intrauterine Device
Brand names
Miudella
Who reports
42,854 reports · 45% serious · 56 with death outcome · 99% female
Used for
Miudella is indicated for prevention of pregnancy in females of reproductive potential for up to 3 years. Miudella is a copper-containing intrauterine system (IUS) indicated for prevention of pregnancy in females of reproductive potential for up to 3 years.( 1 )
What it is
11.1 Miudella Miudella (copper intrauterine system) contains 99.99% pure copper for use as a contraceptive. Copper (Cu) has a molecular weight of 63.546 g/mol. Miudella consists of ten copper .
Boxed warning
RISK OF COMPLICATIONS DUE TO IMPROPER INSERTION Improper insertion of intrauterine systems, including Miudella, increases the risk of complications [see Warnings and Precautions (5.1) ] . Proper training prior to first use of Miudella can minimize the risk of improper Miudella insertion [see Warnings and Precautions (5.1) ].
Causality screen of the 40 strongest signals
What the badges mean
- Labeled adverse reaction The exact term appears in the label's warnings or adverse-reactions sections: a known, expected effect. The FAERS signal confirms the label rather than discovering anything.
- Labeled (related wording) The label describes this effect under different wording (e.g. 'neutropenia' for 'neutrophil count decreased'). Treated as known.
- Likely indication confounding The term appears in the label's indications: reports probably describe the disease being treated (or its progression), not a drug effect. Classic confounding by indication.
- Reporting / coding artifact An administrative, monitoring or exposure term (product issue, off-label use, 'test normal', overdose...). Not a biological reaction; a high PRR here reflects how reports are coded.
- Not in label — unassessed Not found in the label text, not an artifact pattern. This is a genuine candidate for a formal causality assessment (Bradford Hill / WHO-UMC); it has NOT had one here.
Strongest disproportionality signals
Flagged terms (PRR ≥ 2, χ² ≥ 4, n ≥ 10), ranked by PRR; infinite PRRs (no comparator reports) excluded. The EBGM column is a second, shrinkage-based estimate (MGPS) with its 5th percentile EB05 and the BCPNN IC025; a pair flagged by PRR alone is marked PRR-only and should be read as fragile. The strata column recomputes the PRR on serious reports only (and, for the 300 most-reported drugs, adjusted for age band), and flags pairs whose reports are unusually skewed by sex or come mostly from consumers. Each row also shows the PRR against the other drugs of the same FDA class, which removes most confounding by the condition being treated, and a calibrated p-value: on validation, known non-causes average an ROR of about 2, so significance is judged against that empirical null (✓ = p < 0.05 after calibration). 959 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Reproductive complication associated with device | 3,448 | 830,735.0 207,682.8–3,322,954.7ROR 903,423.7 · calibrated p 2e-37 ✓ | 481.3 EB05 468.0 · IC025 +8.8 3/3 methods agree | Labeled (related wording) related wording | serious n=3,446 · 86% consumer | not reported in cached trials |
| Foreign body in reproductive tract | 8,693 | 89,124.5 66,921.7–118,693.5ROR 111,803.9 · calibrated p 1e-48 ✓ | 479.8 EB05 471.4 · IC025 +8.8 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious PRR 608.2 | not reported in cached trials |
| Foreign body in urogenital tract | 731 | 39,138.1 20,283.8–75,518.1ROR 39,817.3 · calibrated p 1e-34 ✓ | 471.1 EB05 443.1 · IC025 +8.4 3/3 methods agree | Not in label — unassessed | serious n=691 · 77% consumer | not reported in cached trials |
| Cervix scarring | 20 | 4,818.6 1,126.3–20,615.4ROR 4,820.9 · calibrated p 1e-13 ✓ | 309.1 EB05 211.3 · IC025 +4.5 3/3 methods agree | Not in label — unassessed | serious n=20 | not reported in cached trials |
| Abnormal uterine bleeding | 1,912 | 1,684.3 1,532.3–1,851.4ROR 1,762.9 · calibrated p 3e-20 ✓ | 374.0 EB05 360.2 · IC025 +8.3 3/3 methods agree | Labeled (related wording) related wording | serious n=1,449 | not reported in cached trials |
| Complication of device removal | 10,000 | 714.8 694.1–736.2ROR 932.1 · calibrated p 6e-17 ✓ | 288.3 EB05 283.6 · IC025 +8.1 3/3 methods agree | Labeled (related wording) related wording | serious PRR 433.4 | not reported in cached trials |
| Fallopian tube adhesion | 10 | 602.3 237.7–1,526.1ROR 602.5 · calibrated p 7e-11 ✓ | 177.9 EB05 103.3 · IC025 +3.2 3/3 methods agree | Not in label — unassessed | serious n=10 | not reported in cached trials |
| Intentional device use issue | 418 | 496.1 432.9–568.5ROR 501.0 · calibrated p 7e-14 ✓ | 242.2 EB05 223.4 · IC025 +7.4 3/3 methods agree | Not in label — unassessed | serious n=365 | not reported in cached trials |
| Embedded device | 4,644 | 440.9 424.2–458.3ROR 494.4 · calibrated p 6e-14 ✓ | 230.5 EB05 225.0 · IC025 +7.8 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 284.0 | not reported in cached trials |
| Complication of device insertion | 8,351 | 404.4 393.5–415.7ROR 502.1 · calibrated p 5e-14 ✓ | 220.2 EB05 216.3 · IC025 +7.7 3/3 methods agree | Labeled (related wording) related wording | serious n=1,018 | not reported in cached trials |
| Device toxicity | 18 | 361.4 196.2–665.8ROR 361.6 · calibrated p 8e-11 ✓ | 169.9 EB05 113.7 · IC025 +4.2 3/3 methods agree | Reporting / coding artifact | serious n=17 | not reported in cached trials |
| Device placement issue | 1,300 | 352.9 328.8–378.9ROR 363.9 · calibrated p 2e-12 ✓ | 203.5 EB05 194.4 · IC025 +7.5 3/3 methods agree | Reporting / coding artifact | serious n=355 · 91% clinician | not reported in cached trials |
| Device material issue | 770 | 301.9 276.0–330.2ROR 307.4 · calibrated p 8e-12 ✓ | 185.1 EB05 174.4 · IC025 +7.3 3/3 methods agree | Reporting / coding artifact | serious n=529 | not reported in cached trials |
| Pregnancy on contraceptive | 515 | 264.6 237.7–294.5ROR 267.8 · calibrated p 3e-11 ✓ | 170.1 EB05 158.1 · IC025 +7.1 3/3 methods agree | Labeled (related wording) related wording | serious n=498 | not reported in cached trials |
| Uterine scar | 79 | 262.5 199.6–345.3ROR 263.0 · calibrated p 7e-11 ✓ | 163.6 EB05 135.5 · IC025 +6.0 3/3 methods agree | Labeled (related wording) related wording | serious n=77 · 93% consumer | not reported in cached trials |
| Device breakage | 11,144 | 194.4 190.6–198.3ROR 262.3 · calibrated p 3e-11 ✓ | 138.8 EB05 136.6 · IC025 +7.1 3/3 methods agree | Reporting / coding artifact | serious PRR 329.8 | not reported in cached trials |
| Cervix injury | 19 | 186.8 110.0–317.3ROR 186.9 · calibrated p 7e-9 ✓ | 119.1 EB05 80.6 · IC025 +4.2 3/3 methods agree | Labeled (related wording) related wording | serious n=19 | not reported in cached trials |
| Salpingectomy | 154 | 180.6 150.1–217.2ROR 181.2 · calibrated p 1e-9 ✓ | 129.5 EB05 113.2 · IC025 +6.3 3/3 methods agree | Not in label — unassessed | serious n=154 · 94% consumer | not reported in cached trials |
| Cervix inflammation | 34 | 167.2 113.2–246.9ROR 167.3 · calibrated p 7e-9 ✓ | 116.4 EB05 87.1 · IC025 +4.9 3/3 methods agree | Not in label — unassessed | serious n=27 | not reported in cached trials |
| Uterine cervical pain | 46 | 157.2 112.7–219.3ROR 157.4 · calibrated p 8e-9 ✓ | 113.3 EB05 88.4 · IC025 +5.2 3/3 methods agree | Labeled (related wording) related wording | serious n=35 | not reported in cached trials |
| Uterine injury | 40 | 149.4 104.8–213.0ROR 149.6 · calibrated p 1e-8 ✓ | 108.5 EB05 83.1 · IC025 +5.0 3/3 methods agree | Labeled (related wording) related wording | serious n=39 · 91% consumer | not reported in cached trials |
| Dyspareunia | 1,064 | 147.9 138.2–158.3ROR 151.7 · calibrated p 4e-9 ✓ | 113.2 EB05 107.6 · IC025 +6.7 3/3 methods agree | Labeled adverse reaction exact term | serious n=731 | not reported in cached trials |
| Coital bleeding | 315 | 127.9 113.0–144.7ROR 128.8 · calibrated p 2e-8 ✓ | 100.7 EB05 91.7 · IC025 +6.3 3/3 methods agree | Labeled adverse reaction exact term | serious n=196 | not reported in cached trials |
| Uterine adhesions | 26 | 125.3 81.4–192.9ROR 125.4 · calibrated p 8e-8 ✓ | 93.0 EB05 66.7 · IC025 +4.5 3/3 methods agree | Labeled (related wording) related wording | serious n=24 · 85% consumer | not reported in cached trials |
| Uterine tenderness | 16 | 115.1 66.7–198.5ROR 115.1 · calibrated p 3e-7 ✓ | 84.0 EB05 54.9 · IC025 +3.8 3/3 methods agree | Not in label — unassessed | serious n=12 | not reported in cached trials |
| Infertility female | 288 | 114.5 100.7–130.2ROR 115.3 · calibrated p 4e-8 ✓ | 92.2 EB05 83.6 · IC025 +6.1 3/3 methods agree | Labeled (related wording) related wording | serious n=285 · 97% consumer | not reported in cached trials |
| Heavy menstrual bleeding | 1,471 | 111.2 105.1–117.6ROR 115.1 · calibrated p 4e-8 ✓ | 90.4 EB05 86.6 · IC025 +6.4 3/3 methods agree | Labeled adverse reaction exact term | serious n=1,184 · 70% consumer | not reported in cached trials |
| Cervical cyst | 44 | 111.0 80.0–154.0ROR 111.1 · calibrated p 1e-7 ✓ | 87.1 EB05 67.6 · IC025 +5.0 3/3 methods agree | Not in label — unassessed | serious n=39 | not reported in cached trials |
| Uterine cervical laceration | 16 | 104.2 60.7–178.8ROR 104.2 · calibrated p 5e-7 ✓ | 78.1 EB05 51.0 · IC025 +3.7 3/3 methods agree | Labeled (related wording) related wording | serious n=15 | not reported in cached trials |
| Administration site indentation | 10 | 102.5 51.8–202.9ROR 102.5 · calibrated p 1e-6 ✓ | 73.3 EB05 42.6 · IC025 +3.0 3/3 methods agree | Not in label — unassessed | serious n=9 | not reported in cached trials |
| Cervical discharge | 15 | 101.8 58.3–177.7ROR 101.8 · calibrated p 7e-7 ✓ | 76.3 EB05 49.1 · IC025 +3.6 3/3 methods agree | Labeled (related wording) related wording | serious n=12 | not reported in cached trials |
| Bacterial vaginosis | 266 | 101.4 88.9–115.7ROR 102.0 · calibrated p 1e-7 ✓ | 83.5 EB05 75.4 · IC025 +6.0 3/3 methods agree | Not in label — unassessed | serious n=184 | not reported in cached trials |
| Device expulsion | 11,180 | 101.3 99.5–103.2ROR 136.7 · calibrated p 1e-8 ✓ | 83.9 EB05 82.6 · IC025 +6.4 3/3 methods agree | Reporting / coding artifact | serious PRR 159.5 | not reported in cached trials |
| Device dislocation | 7,258 | 98.3 96.0–100.6ROR 118.2 · calibrated p 3e-8 ✓ | 81.8 EB05 80.2 · IC025 +6.3 3/3 methods agree | Reporting / coding artifact | serious PRR 98.5 | not reported in cached trials |
| Dysfunctional uterine bleeding | 205 | 97.9 84.3–113.7ROR 98.4 · calibrated p 1e-7 ✓ | 80.9 EB05 72.1 · IC025 +5.9 3/3 methods agree | Labeled (related wording) related wording | serious n=64 · 94% clinician | not reported in cached trials |
| Pregnancy with contraceptive device | 1,486 | 96.4 91.3–101.9ROR 99.9 · calibrated p 1e-7 ✓ | 80.4 EB05 77.1 · IC025 +6.2 3/3 methods agree | Labeled (related wording) related wording | serious PRR 116.2 | not reported in cached trials |
| Laparoscopy | 40 | 90.9 64.9–127.4ROR 91.0 · calibrated p 5e-7 ✓ | 74.0 EB05 56.7 · IC025 +4.8 3/3 methods agree | Labeled adverse reaction exact term | serious n=40 · 100% consumer | not reported in cached trials |
| Uterine pain | 155 | 87.7 73.9–104.0ROR 88.0 · calibrated p 3e-7 ✓ | 73.7 EB05 64.4 · IC025 +5.6 3/3 methods agree | Labeled (related wording) related wording | serious n=115 · 83% consumer | not reported in cached trials |
| Blood copper increased | 26 | 86.4 56.9–131.2ROR 86.5 · calibrated p 1e-6 ✓ | 69.8 EB05 50.1 · IC025 +4.3 3/3 methods agree | Likely indication confounding term in indications; also in warnings | serious n=18 | not reported in cached trials |
| Deformity | 1,339 | 81.5 77.0–86.3ROR 84.1 · calibrated p 4e-7 ✓ | 69.8 EB05 66.7 · IC025 +6.0 3/3 methods agree | Not in label — unassessed | serious PRR 101.4 | not reported in cached trials |
Trial evidence (ClinicalTrials.gov)
✓ Trial adverse-event data found on ClinicalTrials.gov
Largest completed trials with posted results that list Copper as a study intervention. The right-hand column of the signal table shows whether each FAERS term was also recorded in these trials, with a real denominator (0 of 40 signal terms matched).
- NCT00461175 — European Active Surveillance Study for Intrauterine Devices (N=63194, phase n/a; 4 AE terms posted; arms: LNG IUS; Copper IUD)
Caveats: trial populations, doses and follow-up differ from the reporting population; AE terms are sponsor-coded and matched here by wording; absence from a trial list means the term was not reported above the sponsor's frequency threshold, not that it cannot occur.
Most frequently reported reactions
By raw co-report count, regardless of disproportionality. Common terms here are often the illness itself or generic outcomes.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Device expulsion | 11,180 | 101.3 99.5–103.2ROR 136.7 · calibrated p 1e-8 ✓ | 83.9 EB05 82.6 · IC025 +6.4 3/3 methods agree | Reporting / coding artifact | serious PRR 159.5 | not reported in cached trials |
| Device breakage | 11,144 | 194.4 190.6–198.3ROR 262.3 · calibrated p 3e-11 ✓ | 138.8 EB05 136.6 · IC025 +7.1 3/3 methods agree | Reporting / coding artifact | serious PRR 329.8 | not reported in cached trials |
| Complication of device removal | 10,000 | 714.8 694.1–736.2ROR 932.1 · calibrated p 6e-17 ✓ | 288.3 EB05 283.6 · IC025 +8.1 3/3 methods agree | Labeled (related wording) related wording | serious PRR 433.4 | not reported in cached trials |
| Foreign body in reproductive tract | 8,693 | 89,124.5 66,921.7–118,693.5ROR 111,803.9 · calibrated p 1e-48 ✓ | 479.8 EB05 471.4 · IC025 +8.8 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious PRR 608.2 | not reported in cached trials |
| Complication of device insertion | 8,351 | 404.4 393.5–415.7ROR 502.1 · calibrated p 5e-14 ✓ | 220.2 EB05 216.3 · IC025 +7.7 3/3 methods agree | Labeled (related wording) related wording | serious n=1,018 | not reported in cached trials |
| Device dislocation | 7,258 | 98.3 96.0–100.6ROR 118.2 · calibrated p 3e-8 ✓ | 81.8 EB05 80.2 · IC025 +6.3 3/3 methods agree | Reporting / coding artifact | serious PRR 98.5 | not reported in cached trials |
| Pain | 5,820 | 4.7 4.6–4.8ROR 5.2 · calibrated p 0.210 | 4.6 EB05 4.5 · IC025 +2.2 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 7.9 | not reported in cached trials |
| Embedded device | 4,644 | 440.9 424.2–458.3ROR 494.4 · calibrated p 6e-14 ✓ | 230.5 EB05 225.0 · IC025 +7.8 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 284.0 | not reported in cached trials |
| Reproductive complication associated with device | 3,448 | 830,735.0 207,682.8–3,322,954.7ROR 903,423.7 · calibrated p 2e-37 ✓ | 481.3 EB05 468.0 · IC025 +8.8 3/3 methods agree | Labeled (related wording) related wording | serious n=3,446 · 86% consumer | not reported in cached trials |
| Anxiety | 2,930 | 5.1 4.9–5.2ROR 5.4 · calibrated p 0.198 | 5.0 EB05 4.9 · IC025 +2.3 3/3 methods agree | Not in label — unassessed | serious PRR 9.0 · 80% consumer | not reported in cached trials |
| Emotional distress | 2,896 | 11.9 11.5–12.4ROR 12.7 · calibrated p 0.013 ✓ | 11.7 EB05 11.3 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious PRR 16.5 · 91% consumer | not reported in cached trials |
| Off label use (used outside approved label) | 2,771 | 1.6 1.5–1.6ROR 1.6 · calibrated p 0.708 | 1.6 EB05 1.5 · IC025 +0.6 | Reporting / coding artifact | serious PRR 2.4 | not reported in cached trials |
| Injury associated with device | 2,636 | 73.8 70.9–76.8ROR 78.6 · calibrated p 7e-7 ✓ | 64.1 EB05 62.1 · IC025 +5.9 3/3 methods agree | Labeled (related wording) related wording | serious n=2,624 | not reported in cached trials |
| Pelvic pain | 2,595 | 81.4 78.2–84.8ROR 86.6 · calibrated p 3e-7 ✓ | 69.8 EB05 67.5 · IC025 +6.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 103.9 | not reported in cached trials |
| Procedural pain | 2,571 | 50.1 48.2–52.1ROR 53.2 · calibrated p 9e-6 ✓ | 45.5 EB05 44.0 · IC025 +5.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 48.9 | not reported in cached trials |
Unlabeled candidate signals
These flagged terms were not found in the FDA label text and do not match an artifact pattern. They are the pairs that would merit a structured assessment (temporality, dose-response, biological plausibility, consistency across databases, trial or cohort evidence). The screen has not done that; string-matching misses label wording, and a strong PRR can still be stimulated reporting, co-medication, or the disease itself.
- Foreign body in urogenital tract — n=731, PRR 39,138.1
- Cervix scarring — n=20, PRR 4,818.6
- Intentional device use issue — n=418, PRR 496.1
- Salpingectomy — n=154, PRR 180.6
- Cervix inflammation — n=34, PRR 167.2
- Cervical cyst — n=44, PRR 111.0
- Bacterial vaginosis — n=266, PRR 101.4
- Deformity — n=1,339, PRR 81.5
✓ A hand-written Bradford Hill causality assessment exists for this drug: Copper intrauterine device ↔ Foreign body in reproductive tract.
Want to assess one of these properly? The runbook describes the Bradford Hill / trial-evidence workflow used on the assessment page, and handoff_top1000_signals.csv lists the strongest unassessed pairs across all drugs.
Common questions
What are the most reported side effects of Copper?
In FDA FAERS, the most frequently co-reported reaction terms for Copper are complication of device removal, foreign body in reproductive tract, complication of device insertion, pain, embedded device, reproductive complication associated with device. These are report counts, not rates: FAERS has no denominator, reporting is voluntary and uneven, and a term can be reported because of the illness being treated rather than the drug.
Does Copper have an FDA boxed warning?
Yes. The current FDA label carries a boxed warning: RISK OF COMPLICATIONS DUE TO IMPROPER INSERTION Improper insertion of intrauterine systems, including Miudella, increases the risk of complications [see Warnings and Precautions (5.1) ] . Proper training prior to first use of Miudella can minimize the risk of improper Miudella insertion [see Warnings and Precautions (5.1) ].
Do FAERS signals prove that Copper causes these side effects?
No. A disproportionality signal (PRR, ROR) means a reaction is reported more often with this drug than with others in the database. That can reflect a real effect, but also the disease being treated, stimulated reporting after news or litigation, co-medications, or how reports are coded. Causality needs temporality, dose-response, biological plausibility, consistency across data sources and, ideally, trial or cohort evidence. This page screens each term against the FDA label and ClinicalTrials.gov results; it does not establish causation.
Sources & methods
- FDA label via openFDA (set ID 4a75ebac-a765-460d-bb6a-9fbabb0b927d, effective 20260702; matched on
openfda.generic_name.exact:"COPPER") - Bayesian shrinkage measures computed offline over all 1,317,300 cached pairs: BCPNN information component (IC, with Norén closed-form IC025) and MGPS empirical-Bayes geometric mean (EBGM, EB05) with a two-component gamma prior fitted by maximum marginal likelihood (α₁=0.57, β₁=0.02, α₂=1.42, β₂=0.70, w=0.17); unstratified
- FAERS pair statistics from the OpenPV build of 2026-09-14 (openFDA
count=aggregation, fieldpatient.drug.openfda.generic_name.exact, 999 reaction terms, min 3 co-reports); PRR/ROR with 95% CI, chi-square with Yates correction - Serious-only and stratified counts (serious:1, patient.patientsex, primarysource.qualification) from openFDA count queries; serious-only PRR uses the drug serious report total and the term global serious total (N_serious=11,882,979); strata shown only when n ≥ 20
- Seriousness and sex counts from openFDA
count=serious,patient.patientsex,seriousnessdeath - ClinicalTrials.gov API v2 (query
COPPER, results-bearing studies sorted by enrollment)
Page generated 2026-10-14. Label and PubChem text are retrieved automatically and may lag the current label; always check the current prescribing information. OpenPV is a beta research tool of the Open Source Medicine Foundation.