This is best evident by United States data which showed that in 1991, the U. teen birth rate was 61.8 births per 1000 adolescent females as compared to 24.2 births per 1000 adolescent females in 2014.From this historic low of 2014, the teen birth rate further declined by 8% in 2015. teen birth rate is higher than many other developed countries, like Canada and the United Kingdom .Sub-Saharan Africa on the other hand has the highest prevalence of pregnancies among adolescent girls, accounting for 28% of adolescent mothers, with 15% in West and Central Africa, and 13% in Eastern and Southern Africa .
Hence, between 19, the United States teen birth rate decreased by more than half (from 61.8 to 22. teens) . This decline was mainly due to combination of increased number of adolescents waiting for sexual intercourse and increased use of contraceptives by teens [9,10].
Furthermore Teen birth rates differ considerably by age, racial and ethnic group, and region of country.
Such pregnancies have significant detrimental effects on physical and mental health of mother as well as are associated with poor perinatal outcomes.
Hence, present review of literature was carried out to know current trends of adolescent pregnancies all over the world with its psychosocial effects on adolescent mothers.
Of which, 55% resided in Asia and Pacific—with 29% in South Asia alone, including India, and 26% in East Asia and Pacific, including China.
It is estimated that by 2030, the adolescent population of Asia and Pacific regions of world will decline to 48% of total, while that of sub-Saharan Africa will rise to 23% (Figure 1).Though there has been a falling trend in wed or unwed adolescent pregnancies all over the world, especially in developed countries, but still it continues to be a major issue.Adolescent pregnancies usually result from lack of education, poverty, poor awareness and knowledge about contraceptives or fear of using them.Figure 2 & 3 shows the percentages of women aged 20-24 who gave birth by age 18 .It was estimated that in 2010, 36.4 million women aged 20 to 24 had their first live birth before 18 years of age, and 5.6 million before 15 years of age.Worldwide 13 million births annually occur to girls younger than 19 years and around 90% of all teenage births occur in developing countries .Nevertheless, there is significant variation in teenage pregnancy and birth rates between developed countries also, though the teenage pregnancy and birth rate is considerably lower in developed countries as compared to developing .If present trend continues, by 2030, the world will have 26 million more adolescent girls, of which majority will belong to Asia and Pacific regions and sub-Saharan Africa, where they are more prone to face significant higher risks of pregnancy compared to their counterparts in other regions of world .The World Health Organization  defines Teenage Pregnancy as “any pregnancy resulting from a girl 10-19 years of age”, age being defined as her age at time of birth of baby .Table 2 shows demographic and reproductive health variables among Indian childbearing age women .As per the 2005 figures, India had around 50.5 million adolescent women.