A double-blind two-phase cluster randomized controlled trial will be conducted in West Java, Indonesia. Total 308 pregnant women will be recruited from 28 clusters (villages) in Sumedang district. Women who fulfil trial criteria will be randomly selected and invited into the trial. Clusters will be randomly assigned to receive placebo or micronutrient-enriched crackers (MEC) daily, distributed by cadres from 14 weeks to 5 months post-partum. Placebo and intervention crackers (recipe developed from chicken liver and eggshell by Food Scientists at University of Otago and pre-tested for acceptability) will be manufactured locally so they are identical in size, colour, and packaging, with a code known only by the local production manager who will not share the code until the primary outcome has been analysed statistically. Primary outcomes will be birth length and infant linear growth (attained and incremental). Secondary outcomes will be: (a) birth weight; (b) maternal haemoglobin at 37 weeks gestation; (c) volume and breastmilk micronutrient concentrations at 5 months post-partum; (d) maternal dietary intakes at 37 weeks and 5 months post-partum; (e) maternal micronutrient status at 37 weeks and 5 months post-partum; (f) micronutrient status of breastfeeding infants at aged 5 months. Analysis will be by intention to treat. Our earlier research has highlighted a high prevalence of anaemia, micronutrient deficiencies, and impaired infant growth among lactating women and infants in Sumedang district, West Java, Indonesia that were associated with large deficits in their micronutrient intakes. In response to these disturbing findings we have developed, and pretested the acceptability of micronutrient-enriched crackers (MEC) based on powdered eggshells and chicken liver, a readily available and affordable, local animal-source food. We will supply these MEC, manufactured locally, to enrich the micronutrient content of the Indonesian daily diets so there are no longer any dietary shortfalls in micronutrients to a group of pregnant and lactating women in Sumedang district. We envisage that by consuming the MEC for 6 months during pregnancy and for 5 months after delivery, there will be a marked increase in the micronutrient status of the Indonesian mothers as well as in their breast milk concentrations for some micronutrients.