Fig 2. Cortisol concentration in milk samples of participants during the day at all postnatal times (all samples), and 2, 6 and 12 weeks postpartum.

Box plots represent the cortisol concentration of samples grouped in hourly intervals from 5.00 am to 12.00 pm; all samples collected before 05.00 am and after 12.00 pm were grouped separately. The number of samples included in each boxplot is indicated under each boxplot. White circles represent outliers (>1.5× IQR). Some samples (n = 13) were not included in the graphs because the collection time was not available.