Dee Harlow cites several factors that explain why Laos has the highest maternal and infant mortality rates in Southeast Asia:

Many factors contribute to the inaccessibility of the care expectant mothers need including, geographic remoteness, lack of infrastructure and seasonal limitations for travel on rough roads, lack of transport or money to pay, little knowledge of the health requirements of prenatal care or services available, as well as family priorities of working for subsistence living and other household responsibilities

Maternal under-nutrition, which is predominant in Laos, can lead to low infant birthweight leading to poor infant health leading to high risk of mortality from illness or disease.