some interesting facts....

When and where babies arrive

Super Tuesday: The most popular day for babies to make their entrance? It's still Tuesday, which boasted 13,169 births in 2005. That's 16.2 percent more babies than on the average day. Sunday was the slowest day, with 7,374 births. Scheduled labor induction and c-sections may be part of the reason babies were much less frequently born on the weekends, according to the CDC.

Some like it hot: More newborns arrive during the late summer and early fall months of July, August, and September than during any other time of the year. Paul Sutton, a demographer for the CDC's National Center for Health Statistics, says it makes sense if you think about what happens nine months earlier in most of the country — the weather gets colder and people spend more time indoors with their sweeties. Also, some people plan their baby's birth to coincide with summer vacations, especially teachers and other people who get summers off. August had the most birthdays in 2005 at around 369,000, and February had the fewest at about 310,000.

Go west: In 2005, the states with the highest birth rates were mostly west of the Mississippi: Alaska, Arizona, California, Idaho, Nebraska, Nevada, New Mexico, Oklahoma, South Dakota, Texas, and Utah — with Georgia being the lone high-birth-rate state on the other side of the divide. Utah continues to beat every other state, with about 21 babies born per 1,000 people. Vermont has the lowest baby output, with just slightly more than ten babies born per 1,000 people.

All about moms

The waiting game: Over the last three decades, women have been waiting longer to become moms. In 1970, the average age for a first-time mother was about 21. In 2005, the average age of first-time moms was 25.2 years.

More mothering: Birth rates for women in their 20s, 30s, and early 40s are higher than ever and continue to grow. And the fertility rate (an estimate of the average number of births a group of women will have over their lifetimes) increased 2 percent in 2006, to 2,101 births per 1,000 women. In fact, 2006 is the first year since 1971 in which the U.S. fertility rate was above "replacement," the rate at which a generation can exactly replicate itself.

• Women ages 30 to 34: This group saw a 2 percent increase, to 97.7 births per 1,000 women in 2006, the highest rate since 1964. The total number of births, though, was about the same in 2006 as in 2005 (97.7 births per 1,000 women), as the population of women in this group fell about 2 percent.

No wedding necessary: Increases in births to unmarried parents continue to outpace the increases in total births, with the number of babies born to unmarried women (over 1.64 million) rising almost 8 percent in 2006. This total is 20 percent higher than in 2002, when the upswing began. Nearly half (45 percent) of the 6.4 million pregnancies in 2004 occurred among unmarried women. Pregnancy totals among unmarried women increased from over 2.7 million in 1990 to over 2.8 million in 2004, whereas pregnancy totals among married women declined from 4.1 million in 1990 to 3.5 million in 2004.

Seeking care: The number of women seeking prenatal care — which can help women have a healthier pregnancy and healthier babies — rose steadily from 11 percent in 1990 to around 84 percent in 2003, where it remains today.

Weighing in: In 2005, about one-third of pregnant women were outside the weight guidelines for healthy pregnancy, with 13 percent of moms gaining less than 16 pounds and 21 percent gaining more than 40 pounds.

Birth and delivery

Doctor, doctor: In 2005, the vast majority of moms in the United States gave birth in hospitals (99 percent) with the help of a physician (92 percent). Midwives attend about 8 percent of all births (most midwife-attended births are in hospitals), up from less than 1 percent in the mid-1970s. Of the 1 percent of births outside the hospital in 2005, 65 percent were in homes, and 27 percent were in birth centers, numbers that have remained largely the same since 1989.

C-sections soaring: The number of c-sections in 2006 rose to 31.1 percent of all birth s, a 3 percent rise from 2005 and another record high. The c-section rate has climbed 50 percent in the United States over the last decade.

Giving labor a push: The number of women whose labor is induced has more than doubled since 1990. In 2005, it rose 5 percent above the previous year, to about 22.3 percent of births. About 1 in 7 preterm and 1 in 4 term and higher deliveries were induced. Boy power: Boy babies outnumber girl babies, with about 1,049 males for every 1,000 females in 2005 — a ratio that's stayed about the same over the past 60 years.

Early birds: The number of babies born prematurely increased very slightly from 2005 to 2006 (to 12.8 percent from 12.7 percent). But since 1990, the preterm delivery rate has gone up 21 percent. Over half a million babies (1 in 8) are born prematurely in the United States each year.

Little lightweights: The average newborn weight in 2005 was 7 pounds, 5 ounces, almost exactly what it was in 2004. About 8 percent of babies born in 2006 were low birth weight (less than 2,500 grams, or 5 pounds, 8 ounces) — also basically unchanged from 2005. The low-birth-weight rate has risen 19 percent since 1990. Induced labors, cesarean deliveries, older maternal age, and fertility therapies are reasons cited for the earlier trend.