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Study · Measured the body's own peptide · 2019

3 results

Menstrual cycle-related fluctuations in oxytocin concentrations: A systematic review and meta-analysis.

Engel S, Klusmann H, Ditzen B, Knaevelsrud C, Schumacher S

Frontiers in neuroendocrinology17 Nov 2018Cited by 101 (Europe PMC)

PMID30458185 (opens in a new tab)DOI10.1016/j.yfrne.2018.11.002 (opens in a new tab)PepBankPUB-30458185
Publisher pagePubMedAsk about this study
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Summary

The text of this summary is not shown here, because the article license does not allow reuse. Read it at the source (opens in a new tab)

Text rights: Publisher copyright. Results still quote short attributed sentences.

Results from this study3

No result from this study comes from a test of the peptide.

Natural levels measured3

These results measure the body's own peptide. Nobody was given the peptide. They are not evidence about taking it. They are left out of key results, evidence counts and charts.

  1. 01HumanEndogenous levelSystematic reviewOther

    In healthy women, endogenous oxytocin concentrations rose significantly from the early follicular phase to ovulation.

    In plain wordsIn healthy women, the body's own oxytocin levels rose from the early follicular phase to ovulation.

    Peptide
    Oxytocin
    Outcome
    IncreaseOxytocin concentration, early follicular phase to ovulation
    Study

    n = 120

    Outcome group
    Endogenous peptide levels · Endocrine and hormones

    Measurements

    Hedges g
    0.39
    early follicular phase to ovulation

    Source sentences

    Summary
    Data from 13 studies (120 women) showed a significant increase of oxytocin concentrations from the early follicular phase to ovulation (g = 0.39 [0.25; 0.53], p < .001)
    1 context sentence
    Summary · context
    This systematic review and meta-analysis investigated endogenous oxytocin concentrations across menstrual cycle phases in healthy women.

    This result measures the body's own Oxytocin. Nobody was given the peptide. It is not evidence about taking it.

  2. 02HumanEndogenous levelSystematic reviewOther

    In healthy women, endogenous oxytocin concentrations fell significantly from ovulation to the mid-luteal phase.

    In plain wordsIn healthy women, the body's own oxytocin levels fell from ovulation to the mid-luteal phase.

    Peptide
    Oxytocin
    Outcome
    DecreaseOxytocin concentration, ovulation to mid-luteal phase
    Study

    n = 120

    Outcome group
    Endogenous peptide levels · Endocrine and hormones

    Measurements

    Hedges g
    −0.5
    ovulation to mid-luteal phase

    Source sentences

    Summary
    a significant decrease from ovulation to the mid-luteal phase (g = -0.50 [-0.81; -0.18], p < .001).
    1 context sentence
    Summary · context
    This systematic review and meta-analysis investigated endogenous oxytocin concentrations across menstrual cycle phases in healthy women.

    This result measures the body's own Oxytocin. Nobody was given the peptide. It is not evidence about taking it.

  3. 03HumanEndogenous levelSystematic reviewOther

    In healthy women, endogenous oxytocin concentrations did not differ significantly between the early follicular and mid-luteal phases.

    In plain wordsIn healthy women, the body's own oxytocin levels did not differ between the early follicular and mid-luteal phases.

    Peptide
    Oxytocin
    Outcome
    No significant changeOxytocin concentration, early follicular vs mid-luteal phase
    Study

    n: not reported in source

    Outcome group
    Endogenous peptide levels · Endocrine and hormones

    Measurements

    Hedges g
    −0.19
    early follicular vs mid-luteal phase

    Source sentences

    Summary
    There were no significant differences between the early follicular and mid-luteal phase (g = -0.19 [-0.70; -0.32], p = .471).
    1 context sentence
    Summary · context
    This systematic review and meta-analysis investigated endogenous oxytocin concentrations across menstrual cycle phases in healthy women.

    This result measures the body's own Oxytocin. Nobody was given the peptide. It is not evidence about taking it.

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

  1. Version 2Current

    9 Oct 2026, 18:17 UTC

    Study results updated

  2. Version 1

    9 Oct 2026, 02:48 UTC

    First added · source update from Europe PMC

Subjects

Terms as the source lists them.

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