Teen pregnancies are way down, while childbirth among women over 30 is on the rise, according to new statistics from the U.S. government. Unmarried women are giving birth in greater numbers, and the rate of Caesarean deliveries is at an all-time high.

More women are giving birth at a later age, however -- the rate for childbirths among women over 30, about 96 for every 1,000, is the highest it has been in almost 40 years.

More women than ever before are delivering by Caesarean -- 30.2 percent of all births -- the report also found.

The drop in teen pregnancies is likely due to a combination of factors, said Brady Hamilton, a statistician at the National Center for Health Statistics, among them better education, better availability of contraceptions for teens, and programs promoting abstinence before marriage.

More women are focusing on career and education first, he added, which could explain the surge births among older women.

The spike in the rate of childbirth among older women could also be related to the increase in Caesarean deliveries, with more multiple births occurring among older women who seek assistance from fertility experts to become pregnant.

Doctors discourage vaginal delivery after a woman has previously given birth by Caesarean, resulting in a larger number of subsequent Caesarean births overall.

Unmarried women are having children in record numbers, the report also found.