For the first time on record, women over 40 are having more babies than U.S. teenagers, underscoring a dramatic shift in when Americans are starting families. Birth rates among women ages 40 to 49 have climbed 24% over the past decade, while teen births have continued to fall. Washington, D.C., New York and New Jersey now lead the nation in births among women in their 40s. #birth #birthrate #usa #news #science