A district health officer in rural Maharashtra is analyzing vital statistics data from the past 5 years. The infant mortality rate (IMR) has remained stagnant at 45 per 1000 live births despite a 30% increase in institutional deliveries. The crude birth rate (CBR) is 28 per 1000 population and crude death rate (CDR) is 8 per 1000 population. On further investigation, neonatal deaths account for 65% of all infant deaths. What is the most appropriate next step to address the persistently high IMR in this district?