In 1978, some called the birth of the first so-called test tube baby a miracle. Now three decades later, the Bay Area is at the epicenter of continuing research into the science of in vitro fertilization.
"Huge change. The success rate has been significantly improved compared to a decade ago," says Dr. Shehua Shen.
At her lab at UCSF's Center for Reproductive Health, Shehua Shen has helped pioneer new techniques to fertilize eggs and successfully placed the embryos back in the womb. She says some of the most promising research started with screening for genetic markers in embryos before they're even implanted.
"We screen nine chromosomes at a time," says Shen.
The technique currently involves removing a single cell from an embryo when it's just days old to identify genetic disorders like Downs Syndrome. However, future tests could help tell doctors which embryo has the best chance of surviving in the womb.
"What we are doing is try to improve with the selection process," says Dr. Shen.
Researchers say implanting fewer embryos means lowering the number of twins or triplet births, still a major side effect of in vitro.
"The smarter we can get about making better embryos and selecting better embryos and transferring fewer embryos, the healthier babies we'll have," says Dr. Marcelle Cedars with the UCSF Center for Reproductive Health
Other advances include improved methods of freezing and thawing eggs for fertilization later. It's technology that UCSF is using in a program to help cancer patients of child-bearing age become pregnant after treatments like radiation.
Using a wide variety of techniques, UCSF now performs more than 900 in vitro fertilization cycles and averages 200 to 300 births per year. But doctors caution that the technology, even 30 years later, still offers no guarantees.
That's especially true for women in their 40s like Juliette Linzer. It took five in vitro fertilization cycles for her to get pregnant.
"When you have a baby everyone tells you it's so hard, you're going to be so tired, but it's so much easier than the two years before," says Linzer.
The most common question about in vitro is still this: What about success rates after 30 years? They have improved dramatically with 42 percent success now the average at UCSF, but that number is very dependent on age. For women 41 to 42, the success rate drops to 13 percent.