[Israeli] researchers have grown mice in an artificial womb for as long as 11 or 12 days, about half the animal’s natural gestation period.
It’s record for development of a mammal outside the womb, and according to the research team, human embryos could be next—raising huge new ethical questions.
“This sets the stage for other species,” says Jacob Hanna, a developmental biologist at the Weizmann Institute of Science, who led the research team. “I hope that it will allow scientists to grow human embryos until week five.”
Hanna believes lab-grown embryos could be a research substitute for tissue derived from abortions, and possibly a source of tissue for medical treatments as well.
“I do understand the difficulties. I understand. You are entering the domain of abortions,” says Hanna. However, he says he can rationalize such experiments because researchers already study five-day-old human embryos from IVF clinics, which are also destroyed in that process.
“So I would advocate growing it until day 40 and then disposing of it,” says Hanna. “Instead of getting tissue from abortions, let’s take a blastocyst and grow it.”