While raising children is a major responsibility and protracted undertaking for couples, it becomes markedly more demanding and often onerous for lone parents. Children raised in single-parent households generally do not have the same financial means, personal care and parental support available to them as those brought up in two-parent families. Consequently, children in single-parent families are frequently disadvantaged due to comparatively high levels of unemployment, poverty and poor health among such households.
The primary cause of single-parent households in the distant past was parental death due to disease, war, maternal mortality and accidents. As a result of those high adult mortality rates, it is estimated that at least one-third of the children had lost a parent during childhood.
Today in addition to parental death, which fortunately has declined markedly over the past century, socio-cultural factors have arisen as the primary causes for single-parent households. Divorce, separation and abandonment are now major reasons for single-parent families globally. In addition, unplanned pregnancy, intended pregnancy and adoption by those who are unmarried and without partners are among the causes of single-parent households in many Western societies.