There were 13 maternal deaths and 387 infant deaths (below one year) during the period, State Reproductive Child Health Programme Officer Dr R Lalthanga said.
The highest number of infant deaths were reported from the southern district of Saiha and the lowest number was from Mamit district, he said.
The IMR during the last fiscal in the state was 35 and MMR 76.
According to the health department record, 10,857 babies were born during April and September.