Sex-Related Differences in Plasma Oxytocin Levels in Humans.
Level 4 - case-series / case-control
Cross-sectional observational study
PubMed 31015856 · doi:10.2174/1745017901915010058
What was done
Plasma oxytocin concentrations were measured using radioimmunoassay following peptide extraction in 90 healthy participants (45 men and 45 women, mean age 34.9 ± 6.2 years) to evaluate sex-related differences.
What was found
Plasma oxytocin levels (mean ± SD) were significantly higher in women than in men (4.53 ± 1.18 pg/ml vs. 1.53 ± 1.19 pg/ml, p < 0.001).
Why it matters
This study provides comparative baseline data indicating higher circulating oxytocin in healthy women compared to men, informing hypotheses regarding sex-specific social and stress-response mechanisms.
Limits
The study is limited by a small sample size (n = 90) and a cross-sectional design. The abstract reports no control for menstrual cycle phase, hormonal contraceptive use, or time of blood draw, and it did not measure behavioral or clinical correlates.
Cited by
- supports Women get three times as much oxytocin as men.