In Pakistan, breastfeeding is widely practiced. National data suggests that 94% of infants <2 years of age receive breastmilk at some point. However, the introduction of complementary foods often occurs early. At 3 months of age, it is suggested that only 54% of Pakistani infants are exclusively breastfed. This declines with each month of age. Because the production and release of breastmilk is influenced by the frequency and intensity of suckling, early initiation of complementary feeding can reduce breastmilk output. Given that complementary foods are introduced early within Pakistan, we hypothesize that breastmilk composition will change between 1 and 3 months postpartum among those mother-infant pairs if nutritive complementary foods are introduced early (i.e., before 6 months). In this study, we aim to better understand how breastmilk composition changes over time among infants recruited at 1 month of age who are exclusively breastfed or receive only non-nutritive feeds. This is a substudy to the Matiari emPowerment and Preconception Supplementation (MaPPS) Trial (ClinicalTrials.gov Identifier: NCT03287882).

Inclusion Criteria:

• Enrolled in the MaPPS Trial
• Mothers must report practicing exclusive or predominant breastfeeding (i.e., breastmilk only or breastmilk and non-nutritive feeds only)
• The infant must be term-born (>37 weeks gestation)
• Infant must be 1 month + 14 days old at the time of recruitment
• Mothers must be willing to provide a complete breastmilk expression from one breast (either via breast pump or hand expression)
• Able to provide informed consent

Exclusion Criteria:

• Mother reports mixed feeding of her infant with nutritive feeds (i.e., any provision of formula or animal milk)
• The infant was born preterm (earlier than 37 weeks gestation)
• Mother does not wish to provide a complete breast expression of one breast

Mothers and infants enrolled in the MaPPS Trial in Matiari District, Pakistan.

Please contact the Primary Investigator directly for more details.