Louise Brown, the first child conceived by assisted reproductive technology or in vitro fertilization (IVF), as it is commonly known, enters her 30s today. Her 1978 birth, just outside of Manchester, England, caused a stir throughout the world, with many groups claiming that her manner of conception was akin to scientists playing God. Today, she is merely the first of more than 3.5 million children around the globe (more than 250,000 in the U.S.) conceived in a test tube. That accounts for 1.5 percent of all babies born every year.  According to celebrity magazine US Weekly, that number includes Angelina Jolie and Bratt Pitt's twins Knox and Vivienne born in Nice, France, on July 12.

IVF now makes it possible for the more than seven million American women who cannot conceive naturally to have children. But, the technology is not without risks. To increase the odds of a successful pregnancy, several fertilized eggs must be placed in a woman's uterus at a time. More than 30 percent of successful IVF pregnancies result in mothers giving birth to twins, triplets or greater numbers of babies, which increases the chances of low birth-weight and complications during delivery. Scientists are working on better ways to determine which embryos have the best chance of developing into healthy babies so as to cut down on the number of fertilized eggs they load into a hopeful mother's uterus.

Brown's mom tried unsuccessfully for nearly a decade to get pregnant, but failed because of a fallopian tube problem. She and her husband eventually turned to University of Cambridge fertilization experts Robert Edwards and Patrick Steptoe, and on July 25, 1978, Louise Brown was delivered by C-section. Brown is now an administrator at a shipping company in Bristol and the proud mother of an 18-month-old boy named Cameron, whom she conceived naturally.

To mark the 30th anniversary of her birth, the British Fertility Society took a survey of fertility experts to determine if standards should be in place to evaluate whether prospective mothers are fit for IVF. More than 75 percent of those surveyed believe that women who smoke or are obese should be asked to change their lifestyles before undergoing the procedure.

(Credit: iStockphoto/Kiyoshi Takahase)