Revolutionary science has some people questioning what the future will look like when it comes to fertility treatments.
Japanese researchers have discovered a new fertility process called In Vitro Gametogenisis, or IVG, which involves custom-making human eggs and sperm in a lab from any cell in a person's body.
IVG would make it possible for same-sex couples to reproduce, as well as women who might already be in menopause. A single person could even have a child by creating both the egg and sperm from their own genes. Though it wouldn't be a clone, that would make the offspring 100 percent related to them.
So far it's only been done successfully in mice, but could move to human safety trials in the next couple decades.
"If you could make eggs from skin cells, how many eggs can you get?" Greely said. "How many do you want? Hundreds, thousands, millions? Just a question of how long you let the cell line keep dividing."
Greely says some are concerned that people would essentially be closer to "playing God" by the ability to screen as many eggs as you want before transferring one for a possible pregnancy.
"You'll be able to select babies that won't have cystic fibrosis or won't have sickle cell anemia or won't have beta thalassemia or won't be at really, really high risk of breast or ovarian cancer or colon cancer or Alzheimer's disease," Greely said. "But you're not going to be able to select babies that are super smart or super athletic or super musical because it looks like they're literally thousands of different genes involved in those things."
Another big ethical concern is that somebody could steal your DNA and make you a biological parent without you even knowing it.
If a person does have a baby using entirely their own genes, there's a greater risk for recessive genetic diseases. Although, you technically would be able to screen for those diseases.
Greely says these ethical questions should be explored before IVG is available to humans. but he does expect it will be available with time.