Trial reportContraception2012
Lowering oral contraceptive norethindrone dose increases estrogen and progesterone receptor levels with no reduction in proliferation of breast epithelium: a randomized trial.
Trial report in Contraception, 2012. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
4 citing papers in PubMed, 5 citations in OpenAlex.
- The progesterone-receptor modulator, ulipristal acetate, drastically lowers breast cell proliferation.Breast cancer research and treatment · 2022Trial
- Hormonal Contraceptive Formulations and Breast Cancer Risk in Adolescents and Premenopausal Women.JAMA oncology · 2025Article
- Hormonal contraceptive use is associated with reduced central serotonergic activity indexed by the loudness dependence of auditory evoked potentials.Frontiers in human neuroscience · 2025Article
- Biological effects of green tea capsule supplementation in pre-surgery postmenopausal breast cancer patients.Frontiers in oncology · 2013Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
8 authors at 2 institutions in 1 country.
Funding
Abstract
backgroundThis study was conducted to compare breast epithelial-cell proliferation and estrogen and progesterone receptor levels in women taking one of two oral contraceptives (OCs) containing the same dose of estrogen but different doses of the progestin norethindrone (NET). STUDY
designThirty-three women were randomly assigned 1:1 to one of two OCs with 35-mcg ethinylestradiol (EE2) but different doses of NET - 1 or 0.4 mg. At the end of the active pill phase of the third OC cycle, a breast biopsy was performed and the percentages of epithelial cells of the terminal duct lobular units were measured for Ki67 (MIB1), progesterone receptors A and B (PRA and PRB, respectively), and estrogen receptor α (ERα).
resultsThe biopsies from 27 women had sufficient epithelium for analysis. The percentages of cells positive for PRA, PRB and ERα were approximately double with the lower progestin dose (PRA: p=.041; PRB: p=.030; ERα: p=.056). The Ki67 percentage was not reduced with the lower progestin dose (12.5% for 0.4-mg NET vs. 7.8% for 1.0-mg NET).
conclusionsThe increase in PRA-, PRB- and ERα-positive cells with the 60% lower progestin dose OC appears likely to account for its failure to decrease breast-cell proliferation. This breast-cell proliferation result is contrary to that predicted from the results of lowering the medroxyprogesterone acetate dose in menopausal hormone therapy.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.