WASHINGTON — The United States has a brighter demographic outlook than Europe, according to recent numbers provided by the Centers for Disease Control and Prevention.

The United States reported the largest number of children born in 45 years, with 4.3 million births in 2006. Demographic experts aren’t entirely certain what the cause of the increase is. They say it’s the result of a variety of factors.

“It’s been quite a long time since we’ve had a rate this high,” Stephanie Ventura, with the National Center for Health Statistics, told the Washington Post. “It’s a milestone.”

Experts seem divided over whether the numbers represent a temporary increase. University of Toronto economics professor David Foot, however, doesn’t see the change as a baby boomlet. He says it’s more like a “little bump in a plateau.”

“The U.S. has been sitting on a plateau — hovering around 2.1 children per women for over a decade,” said Foot, author of Boom, Bust and Echo. “Even if this number is slightly higher, if you go back and look 10 years ago the number wouldn’t have been much different.”

“Americans like children,” said Nan Marie Astone, associate professor of population, family and reproductive health at Johns Hopkins University. “We are the only people who respond to prosperity by saying, ‘Let’s have another kid.’”

Affluence alone, however, isn’t the only reason being cited for the increase. Among the other influences were: an increased fertility rate, a decreasing abortion rate and the impact of Hispanics as a group on the country’s population rate.

In 2006, the nation’s fertility rate hit a 35-year high of 2.1 — a level commonly accepted as needed for replacement. As such, the United States has the highest fertility rate in the developed world.

The Impact of Immigration

One element of the increase seems to be immigrants, especially from nominally Catholic, Spanish-speaking countries.

“Hispanics and religiosity are the two big hooks” impacting U.S. population, said Foot, “in that order.”

Hispanics, he noted make up 15% of the population but account for 25% of the births.

“That accounts for roughly half of the difference between the U.S. and the rest of the world,” said Foot.

The fertility rate among Hispanics is three children per woman. That’s the highest rate for any group — 40% higher than the U.S. overall. In 2006, there were more than 1 million Hispanic births.

The Washington, D.C.-based research organization the Pew Hispanic Center noted that fertility rates often rise among immigrants who leave their homeland. The rate among Mexican-born women in the United States is 3.2, for example, while the overall rate for Mexico is just 2.4.

It’s not just Hispanics, however, who are having children.

Of particular note was the fact that the birth rate rose in every age, ethnic and racial group. Last month, the CDC reported that the country’s teen birth rate had increased for the first time in 15 years.

Another significant factor is the falling abortion rate. A new report by the pro-abortion Guttmacher Institute showed that the abortion rate is down 25%, its lowest level since the Roe v. Wade made abortion legal in 1973. That amounts to 1.2 million surgical abortions in 2005 vs. 1.6 million in 1990. One in five pregnancies ends in abortion.

The Guttmacher Institute cited three reasons for the drop: more effective use of contraceptives, lower levels of unintended pregnancies, and greater difficulty obtaining abortion in some regions of the country.

The abortion rates were highest in the Northeast and lowest in more rural areas.

Pro-life organizations cite differing reasons for the decrease in abortions.

“Today’s numbers confirm what we have known for years: If women seeking abortion are fully informed about the risks surrounding abortion, the development of their unborn child, and public and private assistance available in their area, they are more likely to reject the idea of abortion,” said Randall O’Bannon, director of education and research with National Right to Life. ”Women’s Right to Know laws, parental involvement laws, bans on partial-birth abortion, all of which continue to be enacted by the states, not only help women facing crisis pregnancies, they also raise the public’s awareness about abortion and the humanity of the unborn child.”

Steven Mosher, president of the Front Royal, Va.-based Population Research Institute, described the “bump” as a “trend that’s been under way for quite a while, and will continue.”

“A generation of abortion survivors turned 20 about 15 years ago,” said Mosher. “They’re missing classmates, siblings, cousins, peers. They know unconsciously the toll abortion has taken in their lives and they are marrying and having children themselves.

“Those who are pro-life tend to average three children. Those who are pro-abortion tend to have one child.”

Religion vs. Religiosity

“Americans are much more religious than Europeans: They believe in God more. They go to church more,” said Charles Westoff, a demographer at Princeton University. “That sort of religious attitude or set of values is strongly correlated with fertility.”

The numbers show regional differences in birth rates. The largest increases are in the Midwest, South, and Rocky Mountain states, whereas the Northeast is comparable with northern Europe.

Yet, the idea that religion affects fertility or birth rates has been described by many as a myth.

“There seems to be very little connection between religion and fertility,” said Foot. “But there does seem to be a connection between religiosity and fertility.”

Brooks said that religiosity is often measured by frequency of attendance at a house of worship.

“Religious identification has no significance in predicting anything,” said Arthur Brooks, professor of public administration at Syracuse University’s Maxwell School of Public Affairs and author of the forthcoming book Gross National Happiness (May, 2008: Basic Books). “People who practice religion have more kids.”

Citing Harvard’s 2000 Social Capital Community Benchmark Survey, Brooks noted that among households where parents are 40 and under, 23% of Mormons have four children or more. Among evangelical Protestants, the number is 10%. Among Catholics, it’s 7% — a rate he added that is the same among agnostics and secularists.

“We’ve become an ethnic tribe,” said Brooks, who is a convert to the Catholic faith. “The Mormons are eating our lunch.”

The question that demographers can’t answer is why those who practice their faith have more children.

Brooks had several theories, all of which he says reinforce one another.

“Practicing religious people tend to be in cultures where people value children and there is social capital where they can receive support,” he said. “They’re less likely to live in big cities, more likely to know their neighbors, and have more stable marriages.”

He noted that it’s a fact that once parents have children, they tend to become more religious.

“Another reason is that those who practice their faith are more attuned to questions of philosophical meaning,” added Brooks.

“Children are one of the ways God talks to us. God is creative and generative. So are we. What’s more viscerally creative and generative than having children?”

Tim Drake is based in

St. Joseph, Minnesota.