Body weight increase in expectant males and helpers of cotton-top tamarin (Saguinus oedipus): a symptom of the Couvade syndrome?
Level 5 - mechanism / opinion, no new human data
Oxford CEBM level 5 due to animal research.
What was done
Researchers monitored body weight changes over 6-month periods across 8 social groups of cotton-top tamarins (Saguinus oedipus). Body weight was assessed across three individual categories (expectant males and helpers) under three reproductive conditions: control (no pregnancy or offspring), pregnancy (pregnancy without offspring), and infant-raising (with offspring).
What was found
The abstract reports directional patterns without numerical values, confidence intervals, or test statistics. Cotton-top tamarins increased body weight during the final trimester of pregnancy and experienced weight reductions during the first trimester of infant rearing.
Why it matters
These observations indicate that pre-birth weight gain occurs not only in expectant fathers but also in non-breeding helpers among cooperatively breeding primates, supporting an energetic preparation hypothesis analogous to aspects of human Couvade syndrome.
Limits
This is an animal study in a specific cooperatively breeding primate, limiting generalizability to humans. The abstract does not report the total individual sample size (n is provided only as 8 groups), baseline weights, magnitude of weight changes, or formal statistical effect sizes.
Cited by
- supports A study of expectant tamarin monkeys fed a standardized diet showed that expectant fathers gained more weight than control male monkeys who were not expecting offspring.