A community-based, randomized control, assessor blinded trial in peri-urban settings of Karachi, Pakistan to study the impact of Lipid-based Nutritional Supplement for Pregnant and Lactating women which is balanced energy-protein (BEP) dietary supplement, a locally produced ready-to-use nutritional product for lactating women (LW) and single prophylaxis dose of Azithromycin for infants, on growth of infants over the period of six months since birth compared to current standard of care. LW and her infant will be enrolled in the trial within 168 hours of the birth and LW will be randomized in either of the arm:

1. Arm A: 'Control Arm', LW will only receive standard of care which comprises of standard nutritional counseling, key messages of exclusive breastfeeding, essential newborn and infant care and immunization.
2. Arm B: 'Nutritional supplement only', LW randomized will recieve nutrition supplement product for next 6 months to be consumed in a dose of 2 sachets of 75 grams per day. Further, LW will also receive standard of care which comprises of standard nutritional counseling, key messages of exclusive breastfeeding, essential newborn and infant care and immunization.
3. Arm C: ''Nutritional supplement plus Azithromycin', LW randomized will receive nutritional supplement product for next 6 months to be consumed in a dose of 2 sachets of 75 grams per day. Further, the infant of LW will receive a single dose of Azithromycin (20mg/kilogram) at day 42 of age. Further, LW will also receive standard of care which comprises of standard nutritional counseling, key messages of exclusive breastfeeding, essential newborn and infant care and immunization.

Study aim is to assess the efficacy of nutritional product in a proposed dose to lactating women for at least 6 months of lactation, alone or in combination of single dose of Azithromycin as 20mg/kg to infants at 42 days of age on lenght velocity as primary, and weight velocity as secondary outcome.

Participants will receive nutrition counseling along with guidance related to exclusive breastfeeding and further assessment will be done to assess breast milk composition, Haemoglobin, Ferritin and Transferrin receptor, and inflammatory biomarkers, as secondary outcomes. Further, this study will also look at the comparison of length-for-age, weight-for-length, and weight-for-age Z scores as other secondary outcome at 6 months of age among three arms.

Inclusion Criteria:

• Mid-upper-arm-circumference of lactating women less than 23.0 cm, whose birth outcome should be captured within 168 hours
• Singleton alive baby
• Intention to stay in the catchment area for the entire duration of the trial after enrolment
• Intention to breastfeed the child for at least 6 months
• Voluntary written consent

Exclusion Criteria:

• Weight of newborn at first assessment, within 168 hours of birth is less than 1500 gm
• Newborn with known congenital anomaly or sign of serious illness based of study physician's assessment before enrollment.
• Lactating women has known allergies to peanut, lentils, chickpea or dairy products.
• Lactating woman who have some serious medical illness/condition due to which she is not able to or not willing to breastfeed the child, like breast cancer, inverted nipples.
• Previous enrolment in the same trial.

Lactating women