2.4. Supplement Intake
Information was collected on all supplements consumed from 6 months before pregnancy until enrollment and approximately every 4 to 6 weeks thereafter through 30 days postpartum. The average intake of each nutrient throughout pregnancy was added to the baseline dietary intake of the nutrient. On each occasion, the study coordinator asked about and recorded the supplement intake, including any changes such as discontinuing a supplement, starting a new supplement, or a change in the serving/dose or frequency of a current supplement (i.e., taking two capsules instead of one or taking it 5 days per week instead of 7). Changes to the dose or frequency of a supplement were tracked to obtain the best representation of the participant’s intake. Details were recorded for each unique supplement reported by a participant, including the brand and name of the supplement, start date, stop date (if applicable), dose or serving size consumed, and frequency (number of days per week) the supplement was taken. If the start and/or stop dates were unknown, staff asked probing questions to estimate the approximate month or season of intake. Participants were encouraged to bring bottles or take pictures of supplement labels so that staff could confidently identify the exact supplement.Of the 93 participants whose supplement intake data were not included, 16 did not use a dietary supplement during their pregnancy. The remaining 77 participants reported taking one or more supplements; however, they did not provide enough detail to estimate the nutrient content of the supplement.