Heterogeneous cortisol patterns during the peripartum: Insights from a longitudinal trajectory analysis.

Area of Science:

• Endocrinology
• Neuroscience
• Reproductive Health

Background:

• The maternal hypothalamic-pituitary-adrenal (HPA) axis shows significant changes during pregnancy and postpartum.
• Cortisol secretion patterns exhibit considerable heterogeneity and contradictory findings in peripartum research.
• Individual cortisol secretion patterns and their determinants are not well understood.

Purpose of the Study:

• To identify distinct maternal cortisol secretion patterns during the peripartum period.
• To explore associations between cortisol trajectories and sociodemographic/psychological factors.
• To understand heterogeneity in HPA axis regulation during pregnancy and postpartum.

Main Methods:

• Longitudinal cohort study of 127 healthy pregnant women.
• Salivary cortisol measured at five time points from late pregnancy to 8 weeks postpartum.
• Group-based trajectory modeling applied to identify distinct cortisol secretion patterns.

Main Results:

• Two distinct cortisol trajectory groups identified: a majority (79-86%) with stable, lower levels, and a subgroup (14-21%) with consistently elevated, variable levels.
• High classification stability (98-99%) for trajectory groups.
• No significant associations found between sociodemographic or psychological variables and group membership.

Conclusions:

• Two distinct maternal cortisol trajectories exist across the peripartum period, indicating heterogeneity in HPA axis regulation.
• Unmeasured factors, potentially genetic or epigenetic, may influence these cortisol patterns.
• Distinct cortisol trajectories could explain inconsistencies in previous peripartum cortisol research and highlight differing neuroendocrine regulation modes.