Estrogens and Conjugated side effects: what 59,020 FDA adverse event reports show
Drug class
Estrogen
Label matched
Estrogens, Conjugated (Estrogens, Conjugated)
Who reports
59,020 reports · 71% serious · 1,852 with death outcome · 100% female
Used for
Conjugated estrogens tablets is a mixture of estrogens indicated for: •Treatment of Moderate to Severe Vasomotor Symptoms due to Menopause. ( 1.1 ) •Treatment of Moderate to Severe Vulvar and Vaginal Atrophy due to Menopause ( 1.2 ) •Treatment of Hypoe.
What it is
Conjugated estrogens tablets, USP for oral administration contains a mixture of CE purified from pregnant mares' urine and consists of the sodium salts of water-soluble estrogen sulfates blended to represent the average composition of material derived from pregnant mares' urine.
Boxed warning
ENDOMETRIAL CANCER, CARDIOVASCULAR DISORDERS, BREAST CANCER and PROBABLE DEMENTIA WARNING: ENDOMETRIAL CANCER, CARDIOVASCULAR DISORDERS, BREAST CANCER and PROBABLE DEMENTIA See full prescribing information for complete boxed warning.
Causality screen of the 40 strongest signals
What the badges mean
- Labeled — boxed warning The term (or its clinical synonym) appears in the FDA boxed warning: causality is regulator-recognised and considered serious.
- 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.
- Lab value / disease marker A laboratory result, investigation or disease-activity marker (antibody positive, CRP abnormal, swollen joint count) not described in the label. These usually mirror the monitored disease or testing protocol rather than a drug effect; not screened further.
- 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). 1,184 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 |
|---|---|---|---|---|---|---|
| Contralateral breast cancer | 133 | 636.9 478.8–847.2ROR 638.3 · calibrated p 1e-14 ✓ | 219.2 EB05 189.7 · IC025 +6.7 3/3 methods agree | Not in label — unassessed | serious n=133 · 100% consumer | no trial arm names this drug |
| Progesterone receptor assay positive | 600 | 629.9 551.0–720.0ROR 636.3 · calibrated p 5e-15 ✓ | 223.8 EB05 209.2 · IC025 +7.4 3/3 methods agree | Lab value / disease marker | serious n=593 · 72% consumer | no trial arm names this drug |
| Oestrogen receptor assay positive | 693 | 551.8 489.8–621.7ROR 558.4 · calibrated p 2e-14 ✓ | 213.4 EB05 200.4 · IC025 +7.4 3/3 methods agree | Lab value / disease marker | serious n=685 | no trial arm names this drug |
| Breast cancer in situ | 494 | 222.3 198.6–248.7ROR 224.1 · calibrated p 2e-10 ✓ | 135.6 EB05 125.8 · IC025 +6.8 3/3 methods agree | Not in label — unassessed | serious n=490 | no trial arm names this drug |
| Biopsy breast abnormal | 33 | 189.1 123.8–288.8ROR 189.2 · calibrated p 3e-9 ✓ | 115.0 EB05 85.7 · IC025 +4.9 3/3 methods agree | Not in label — unassessed | serious n=33 | no trial arm names this drug |
| Malignant breast lump removal | 47 | 188.9 132.5–269.3ROR 189.0 · calibrated p 2e-9 ✓ | 117.2 EB05 91.7 · IC025 +5.3 3/3 methods agree | Not in label — unassessed | serious n=47 | no trial arm names this drug |
| Breast cancer female | 8,868 | 175.4 171.2–179.7ROR 206.2 · calibrated p 3e-10 ✓ | 117.1 EB05 115.1 · IC025 +6.8 3/3 methods agree | Not in label — unassessed | serious PRR 95.3 · 89% consumer | no trial arm names this drug |
| Breast microcalcification | 30 | 116.5 77.1–176.1ROR 116.6 · calibrated p 1e-7 ✓ | 83.2 EB05 61.1 · IC025 +4.6 3/3 methods agree | Not in label — unassessed | serious n=30 | no trial arm names this drug |
| Bronchial neoplasm | 33 | 113.1 76.4–167.5ROR 113.2 · calibrated p 1e-7 ✓ | 81.8 EB05 60.9 · IC025 +4.7 3/3 methods agree | Not in label — unassessed | serious n=33 | no trial arm names this drug |
| Ovarian cancer metastatic | 164 | 86.1 72.6–102.1ROR 86.3 · calibrated p 4e-7 ✓ | 68.7 EB05 60.4 · IC025 +5.6 3/3 methods agree | Likely indication confounding term in indications; also in warnings | serious n=164 · 100% consumer | no trial arm names this drug |
| Breast cancer metastatic | 1,683 | 66.1 62.8–69.6ROR 68.0 · calibrated p 2e-6 ✓ | 55.7 EB05 53.5 · IC025 +5.7 3/3 methods agree | Likely indication confounding term in indications; also in warnings | serious PRR 46.1 · 96% consumer | no trial arm names this drug |
| Breast operation | 105 | 52.6 42.8–64.6ROR 52.7 · calibrated p 1e-5 ✓ | 45.5 EB05 38.6 · IC025 +4.9 3/3 methods agree | Reporting / coding artifact | serious n=105 | no trial arm names this drug |
| Fibrocystic breast disease | 91 | 49.3 39.6–61.4ROR 49.4 · calibrated p 2e-5 ✓ | 43.0 EB05 36.1 · IC025 +4.8 3/3 methods agree | Labeled (related wording) related wording | serious n=90 | no trial arm names this drug |
| Schizoaffective disorder | 189 | 41.8 35.9–48.6ROR 41.9 · calibrated p 4e-5 ✓ | 37.3 EB05 33.1 · IC025 +4.9 3/3 methods agree | Not in label — unassessed | serious n=189 | no trial arm names this drug |
| Breast cancer | 9,643 | 40.5 39.7–41.3ROR 48.2 · calibrated p 2e-5 ✓ | 36.4 EB05 35.8 · IC025 +5.2 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 29.6 · 90% consumer | no trial arm names this drug |
| Bronchial haemorrhage | 32 | 40.1 27.8–57.8ROR 40.1 · calibrated p 9e-5 ✓ | 35.4 EB05 26.2 · IC025 +4.0 3/3 methods agree | Not in label — unassessed | serious n=32 | no trial arm names this drug |
| Sinus rhythm | 44 | 39.5 29.0–54.0ROR 39.6 · calibrated p 8e-5 ✓ | 35.1 EB05 27.3 · IC025 +4.2 3/3 methods agree | Not in label — unassessed | serious n=44 · 100% clinician | no trial arm names this drug |
| Atrophic vulvovaginitis | 69 | 37.1 29.0–47.6ROR 37.2 · calibrated p 1e-4 ✓ | 33.4 EB05 27.3 · IC025 +4.4 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=47 | no trial arm names this drug |
| Nasal turbinate hypertrophy | 34 | 35.3 24.8–50.2ROR 35.3 · calibrated p 2e-4 ✓ | 31.6 EB05 23.7 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious n=34 | no trial arm names this drug |
| Endometrial ablation | 31 | 34.0 23.5–49.1ROR 34.0 · calibrated p 2e-4 ✓ | 30.5 EB05 22.5 · IC025 +3.8 3/3 methods agree | Not in label — unassessed | serious n=31 | no trial arm names this drug |
| Mammogram abnormal | 57 | 32.8 25.0–43.0ROR 32.8 · calibrated p 2e-4 ✓ | 29.8 EB05 23.8 · IC025 +4.1 3/3 methods agree | Lab value / disease marker | serious n=53 | no trial arm names this drug |
| Cystocele | 67 | 29.8 23.2–38.2ROR 29.8 · calibrated p 3e-4 ✓ | 27.3 EB05 22.3 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious n=60 | no trial arm names this drug |
| Rectocele | 46 | 29.2 21.6–39.4ROR 29.2 · calibrated p 4e-4 ✓ | 26.8 EB05 20.9 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious n=44 | no trial arm names this drug |
| Vulvovaginal burning sensation | 441 | 27.7 25.1–30.5ROR 27.9 · calibrated p 4e-4 ✓ | 25.7 EB05 23.7 · IC025 +4.5 3/3 methods agree | Not in label — unassessed | serious n=88 · 77% consumer | no trial arm names this drug |
| Breast calcifications | 56 | 26.6 20.3–34.9ROR 26.6 · calibrated p 6e-4 ✓ | 24.6 EB05 19.7 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious n=50 | no trial arm names this drug |
| Vulvovaginal dryness | 221 | 26.2 22.8–30.0ROR 26.3 · calibrated p 6e-4 ✓ | 24.4 EB05 21.8 · IC025 +4.3 3/3 methods agree | Not in label — unassessed | serious n=87 | no trial arm names this drug |
| Vaginal disorder | 65 | 25.7 20.0–33.1ROR 25.8 · calibrated p 7e-4 ✓ | 23.9 EB05 19.4 · IC025 +3.9 3/3 methods agree | Likely indication confounding term in indications; also in warnings | serious n=30 · 100% consumer | no trial arm names this drug |
| Ovarian cancer | 612 | 25.1 23.1–27.2ROR 25.3 · calibrated p 6e-4 ✓ | 23.5 EB05 21.9 · IC025 +4.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 19.0 · 87% consumer | no trial arm names this drug |
| Vulvovaginal discomfort | 289 | 24.9 22.1–28.0ROR 25.0 · calibrated p 7e-4 ✓ | 23.3 EB05 21.1 · IC025 +4.3 3/3 methods agree | Not in label — unassessed | serious n=58 · 73% consumer | no trial arm names this drug |
| Mastectomy | 112 | 24.3 20.1–29.4ROR 24.3 · calibrated p 9e-4 ✓ | 22.7 EB05 19.4 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious n=112 | no trial arm names this drug |
| Benign breast neoplasm | 64 | 23.6 18.3–30.4ROR 23.6 · calibrated p 0.001 ✓ | 22.0 EB05 17.9 · IC025 +3.8 3/3 methods agree | Labeled (related wording) related wording | serious n=59 | no trial arm names this drug |
| Vulvovaginal erythema | 49 | 22.2 16.6–29.7ROR 22.2 · calibrated p 0.001 ✓ | 20.8 EB05 16.3 · IC025 +3.6 3/3 methods agree | Not in label — unassessed | 100% consumer | no trial arm names this drug |
| Bladder prolapse | 73 | 22.2 17.5–28.1ROR 22.2 · calibrated p 0.001 ✓ | 20.8 EB05 17.1 · IC025 +3.8 3/3 methods agree | Not in label — unassessed | serious n=61 | no trial arm names this drug |
| Vulvovaginal pain | 234 | 18.2 16.0–20.8ROR 18.3 · calibrated p 0.003 ✓ | 17.4 EB05 15.6 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious n=70 · 77% consumer | no trial arm names this drug |
| Blood oestrogen decreased | 33 | 18.1 12.7–25.6ROR 18.1 · calibrated p 0.004 ✓ | 17.0 EB05 12.6 · IC025 +3.2 3/3 methods agree | Likely indication confounding term in indications; also in warnings | – | no trial arm names this drug |
| Breast cancer recurrent | 151 | 17.8 15.1–21.0ROR 17.9 · calibrated p 0.003 ✓ | 17.0 EB05 14.8 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious n=151 · 100% consumer | no trial arm names this drug |
| Breast cyst | 83 | 17.3 13.9–21.6ROR 17.3 · calibrated p 0.004 ✓ | 16.5 EB05 13.7 · IC025 +3.6 3/3 methods agree | Labeled (related wording) related wording | serious n=76 | no trial arm names this drug |
| Vulvovaginal pruritus | 225 | 16.5 14.5–18.9ROR 16.6 · calibrated p 0.005 ✓ | 15.8 EB05 14.1 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious n=53 · 80% consumer | no trial arm names this drug |
| Breast neoplasm | 42 | 15.1 11.1–20.5ROR 15.1 · calibrated p 0.008 ✓ | 14.3 EB05 10.9 · IC025 +3.1 3/3 methods agree | Labeled adverse reaction exact term | serious n=40 | no trial arm names this drug |
| Endometrial cancer | 89 | 14.9 12.1–18.4ROR 14.9 · calibrated p 0.008 ✓ | 14.2 EB05 11.9 · IC025 +3.4 3/3 methods agree | Labeled — boxed warning exact term | serious n=89 · 100% consumer | no trial arm names this drug |
Trial evidence (ClinicalTrials.gov)
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 |
|---|---|---|---|---|---|---|
| Breast cancer | 9,643 | 40.5 39.7–41.3ROR 48.2 · calibrated p 2e-5 ✓ | 36.4 EB05 35.8 · IC025 +5.2 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 29.6 · 90% consumer | no trial arm names this drug |
| Breast cancer female | 8,868 | 175.4 171.2–179.7ROR 206.2 · calibrated p 3e-10 ✓ | 117.1 EB05 115.1 · IC025 +6.8 3/3 methods agree | Not in label — unassessed | serious PRR 95.3 · 89% consumer | no trial arm names this drug |
| Drug ineffective (drug did not work) | 3,432 | 0.9 0.9–1.0ROR 0.9 · calibrated p 0.256 | 0.9 EB05 0.9 · IC025 -0.2 PRR-only: not supported by EBGM or IC | Reporting / coding artifact | serious PRR 0.8 | no trial arm names this drug |
| Nausea | 2,404 | 1.1 1.0–1.1ROR 1.1 · calibrated p 0.363 | 1.1 EB05 1.0 · IC025 +0.0 | Labeled adverse reaction exact term | serious PRR 1.0 | no trial arm names this drug |
| Headache | 2,353 | 1.3 1.3–1.4ROR 1.4 · calibrated p 0.542 | 1.3 EB05 1.3 · IC025 +0.3 | Labeled adverse reaction exact term | serious PRR 1.3 | no trial arm names this drug |
| Pain | 2,295 | 1.3 1.3–1.4ROR 1.3 · calibrated p 0.535 | 1.3 EB05 1.3 · IC025 +0.3 | Labeled adverse reaction exact term | serious PRR 1.2 | no trial arm names this drug |
| Fatigue (tiredness) | 2,278 | 1.0 1.0–1.1ROR 1.0 · calibrated p 0.335 | 1.0 EB05 1.0 · IC025 -0.0 PRR-only: not supported by EBGM or IC | Labeled (related wording) related wording | serious PRR 1.1 | no trial arm names this drug |
| Off label use (used outside approved label) | 2,219 | 0.9 0.9–0.9ROR 0.9 · calibrated p 0.246 | 0.9 EB05 0.9 · IC025 -0.2 PRR-only: not supported by EBGM or IC | Reporting / coding artifact | serious PRR 0.7 | no trial arm names this drug |
| Breast cancer metastatic | 1,683 | 66.1 62.8–69.6ROR 68.0 · calibrated p 2e-6 ✓ | 55.7 EB05 53.5 · IC025 +5.7 3/3 methods agree | Likely indication confounding term in indications; also in warnings | serious PRR 46.1 · 96% consumer | no trial arm names this drug |
| Dizziness | 1,680 | 1.2 1.1–1.3ROR 1.2 · calibrated p 0.444 | 1.2 EB05 1.2 · IC025 +0.2 | Labeled adverse reaction exact term | serious PRR 1.1 | no trial arm names this drug |
| Dyspnoea (shortness of breath) | 1,658 | 1.0 1.0–1.1ROR 1.0 · calibrated p 0.335 | 1.0 EB05 1.0 · IC025 -0.0 PRR-only: not supported by EBGM or IC | Not in label — unassessed | serious PRR 0.9 | no trial arm names this drug |
| Malaise (feeling unwell) | 1,611 | 1.3 1.2–1.4ROR 1.3 · calibrated p 0.516 | 1.3 EB05 1.2 · IC025 +0.3 | Not in label — unassessed | serious PRR 1.1 | no trial arm names this drug |
| Diarrhoea (diarrhea) | 1,560 | 0.9 0.8–0.9ROR 0.9 · calibrated p 0.217 | 0.9 EB05 0.8 · IC025 -0.3 PRR-only: not supported by EBGM or IC | Labeled adverse reaction exact term | serious PRR 0.8 | no trial arm names this drug |
| Arthralgia (joint pain) | 1,489 | 1.3 1.2–1.3ROR 1.3 · calibrated p 0.498 | 1.3 EB05 1.2 · IC025 +0.3 | Labeled adverse reaction exact term | serious PRR 1.4 | no trial arm names this drug |
| Anxiety | 1,449 | 1.8 1.7–1.9ROR 1.8 · calibrated p 0.847 | 1.8 EB05 1.7 · IC025 +0.8 | Labeled adverse reaction exact term | serious PRR 1.7 | no trial arm names this drug |
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.
- Contralateral breast cancer — n=133, PRR 636.9
- Breast cancer in situ — n=494, PRR 222.3
- Biopsy breast abnormal — n=33, PRR 189.1
- Malignant breast lump removal — n=47, PRR 188.9
- Breast cancer female — n=8,868, PRR 175.4
- Breast microcalcification — n=30, PRR 116.5
- Bronchial neoplasm — n=33, PRR 113.1
- Schizoaffective disorder — n=189, PRR 41.8
- Bronchial haemorrhage — n=32, PRR 40.1
- Sinus rhythm — n=44, PRR 39.5
✓ A hand-written Bradford Hill causality assessment exists for this drug: Conjugated Estrogens And Medroxyprogesterone Acetate ↔ Breast Cancer.
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 Estrogens and Conjugated?
In FDA FAERS, the most frequently co-reported reaction terms for Estrogens and Conjugated are breast cancer, breast cancer female, nausea, headache, pain, fatigue. 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 Estrogens and Conjugated have an FDA boxed warning?
Yes. The current FDA label carries a boxed warning: ENDOMETRIAL CANCER, CARDIOVASCULAR DISORDERS, BREAST CANCER and PROBABLE DEMENTIA WARNING: ENDOMETRIAL CANCER, CARDIOVASCULAR DISORDERS, BREAST CANCER and PROBABLE DEMENTIA See full prescribing information for complete boxed warning.
Do FAERS signals prove that Estrogens and Conjugated 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 b17eca23-f387-4243-a76a-bcf6b88aeef9, effective 20260825; matched on
openfda.generic_name.exact:"ESTROGENS, CONJUGATED") - 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, 1,224 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
ESTROGENS, 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.