Even though the mean age at childbirth has increased in all countries in the recent decades, a non-negligible proportion of women still give birth at a very early age. The graph below shows the percentage of women of three different cohorts who have given birth before the age of 20. The data reveal a sharp East-West European contrast, with much higher percentages of women experiencing early childbearing in the East than in the West. Among women born in 1975-79, around 4 percent gave birth before the age of 20 on average in the Western European countries represented in the graph, against 17 percent in the East, although with very large cross-national differences. The reasons for early childbearing are complex but often involve a combination of poverty, low education and limited access to contraception. Universal access to sexual and reproductive health-care services and a reduction of adolescent birth rate are at the core of the United Nations Sustainable Development Goals. Data from the Generations and Gender Survey help to monitor these demographic trends.