Combined oral contraceptive,
does it really help with Relief of primary dysmenorrhea?
research showsCombined oral contraceptives are rated B because multiple randomized trials show a moderate reduction in primary dysmenorrhea versus placebo. Six placebo-controlled trials with 588 participants produced an SMD of -0.58 (95% CI -0.74 to -0.41), equivalent to about 0.7 to 1.3 points on a 0-to-6 total score.
ads claimEstablished contraceptive efficacy does not automatically prove dysmenorrhea efficacy. This grade uses only trials that directly measured menstrual pain.
Useful facts when choosing a product
- Harada 2021 distinguished 251 randomized from 245 in the main analysis.
- Contraceptive evidence from verdict 932 was not transferred.
Chamgap Semantic Classification Code
Candidate index · review held
UNK.combined-oral-contraceptive-containing-estrogen-and-progestin.oral.primary-dysmenorrhea.relieve.MULTIUnknown > Combined oral contraceptive containing estrogen and progestin > Oral > primary dysmenorrhea > Symptom-relief claim > Multiple: primary unresolved
An automated migration candidate, not an issued permanent code; exact claim scope remains under review. This machine-generated migration candidate helps retrieval but is not a permanent assignment. The original verdict ID and URL remain authoritative.
What the research actually shows
Harada 2021 enrolled both primary and secondary dysmenorrhea, randomized 251, and analyzed 245; total dysmenorrhea score changed by -1.8 with cyclic treatment, -3.1 with extended treatment, and -0.9 with placebo, with both active regimens at P<0.01, so the primary endpoint succeeded. Its mixed population is indirect for a primary-only claim. Cochrane 2023 reviewed 21 trials and 3,723 participants; six placebo-controlled pain trials in primary dysmenorrhea with 588 participants yielded SMD -0.58, 95% CI -0.74 to -0.41, I-squared 28%. Manufacturers funded 11 studies, but government-funded work was also present, giving I1. verdict 932, which is A with 80 points, concerns contraception in the same drug class, and that evidence was not transferred. In the same indication, verdict 1034, which is B with 70 points, and verdict 857, which is B with 75 points, concern mefenamic acid and ibuprofen; verdict 453, which is C with 57 points, and verdict 575, which is C with 48 points, concern ginger and fennel.
Why this is classified as B (72)
P, R2, I1, E+, and B0 derive B with 72 points.
Counterpoint. Contraceptive needs, bleeding preference, contraindications, and personal preference matter alongside pain relief.
Rejudgment record. Cross-check applied — Multiple placebo-controlled trials including independent work reproduced moderate relief of primary dysmenorrhea pain
| Endpoint | P | Symptom or function itself is the target - including patient reports and performance tests |
| Replication | R2 | Independently replicated across trials |
| Independence | I1 | Mixed funding sources |
| Effect size | E+ | Meets the clinically important threshold |
Stored derived and displayed grades match; this is not a current recalculation or validity check (B).
Sub-claim grades by effect
This ingredient is marketed for several effects. A single overall grade blends strong and weak claims together, so each effect is graded separately here. The overall grade reflects the strongest disconfirming or core claim.
| Effect (sub-claim) | Grade | Basis |
|---|---|---|
| Reduction in primary dysmenorrhea pain score after treatment | B | Six trials reproduced a moderate effect. |
| Increase in pain-improvement responders | B | Six trials with 717 participants produced RR 1.65. |
| Reduction in dysmenorrhea-related absence | C | Evidence is low certainty from two trials and 148 participants. |
Cross-check — AI research and Codex final gate
Evidence Table
| Study | Design | Sample | Funding | Endpoint | Result | Weight |
|---|---|---|---|---|---|---|
| Harada T and Momoeda M. 2021 | Randomized double-blind three-arm placebo-controlled trial in a mixed primary and secondary dysmenorrhea population | 251 randomized; 245 in the main analysis | Manufacturer sponsorship from Nobelpharma Co., Ltd. | Change in total dysmenorrhea score | Cyclic -1.8, extended -3.1, placebo -0.9; both active regimens P<0.01, primary endpoint succeeded | Contemporary direct randomized trial with mixed-population indirectness for a primary-only claim |
| Schroll JB et al. 2023 | Cochrane systematic review and meta-analysis | 21 trials and 3,723 participants overall; six placebo-controlled primary-dysmenorrhea pain trials with 588 | Academic Cochrane review; 11 manufacturer-funded trials plus government-funded work | Post-treatment pain score and pain improvement | SMD -0.58 (95% CI -0.74 to -0.41), I-squared 28%; primary efficacy conclusion positive | Key replicated synthesis |
Receipt — 2 References
All 2 cited sources were verified for existence at the original page (as of 2026-07-24).
Final verification and publication gate: Codex · Evidence date: 2026-07-24 · Corrections: none
Cite this verdict
[Chamgap] Combined oral contraceptive x relief of primary dysmenorrhea — Evidence Grade B·72. 2 cited sources checked. Source: https://chamgap.com/en/verdicts/womens/combined-oral-contraceptive-primary-dysmenorrhea-pain/ · CC BY 4.0CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.
What this document does and does not do
Chamgap is an information source. It reports what research has and has not confirmed; it does not tell readers what to take or buy. That decision belongs to readers and, when needed, medical or legal professionals. This verdict reflects literature available up to the search date and may change as new research appears. Nothing here is medical advice.