Access to things like contraception and prenatal care, and cultural traditions, shape the number of children that are born.

获得避孕和产前护理等服务以及文化传统决定了出生儿童的数量。

It is sure to set off a battle between America's two political parties as the numbers will shape political elections for years to come.

它肯定会引发美国两大政党之间的争斗，因为这些数字将会影响到未来几年的政治选举。