In a statement released on Tuesday - ahead of Thursday's World Health Day - the WHO's Western Pacific office, which is based in Manila, urged the international community to take action to improve the health and well-being of mothers and children.
It noted that more than four years ago, governments worldwide had made a commitment to reduce maternal deaths by three-quarters and child mortality by two-thirds by 2015.
But the commitment "will not be met at the current pace unless rapid and coordinated action is taken now", the WHO warned.
"Affordable and effective means to prevent death and suffering are available, but many of these interventions have yet to reach every mother and child," noted Shigeru Omi, director for the WHO Western Pacific region.
"Too many mothers and children are dying or suffering from the effects of ill-health, poor nutrition and inadequate health care," he added.
More than 70% of maternal and child deaths are caused by preventable and treatable conditions, such as haemorrhage, infection, unsafe abortion, high blood pressure, neo-natal cases, pneumonia, post-neo-natal diarrhoea, malaria and measles, the WHO said.
Almost all deaths and illnesses of mothers and children occur in low and middle-income countries, where the poor and disadvantaged suffer the most.
More than 70% of deaths are
caused by preventable conditions
The WHO said it hoped to raise awareness about the extent of illness, suffering and death among mothers and children on World Health Day.
It noted that the World Health Day's slogan, "Make every mother and child count", aims at bringing home the message that there are affordable and effective interventions that can prevent death and suffering.
"The health of mother and children, and its impact on social and economic development, cannot be overstated," Omi said.
"The future will be healthier and more productive for all societies if we act now and make every mother and child count."