FYI for anyone who wants an overview of where the technology for ectogenesis is at, this Atlantic article is a good one.
Some relevant passages:
Since Liu’s mouse experiments, the medical community has more or less abandoned in-vitro gestation. The past decade saw a renaissance in transplant technology, and advances in the burgeoning field of human prenatal epigenetics have rendered gestation outside a mother’s body a less plausible concept. Scientists are learning more about the interplay between fetal development and the mother’s whole body—not just her uterus.
“The fetus gets an advantage by developing within a maternal body,” says Janet DiPietro, associate dean for research at the Johns Hopkins Bloomberg School of Public Health. DiPietro oversees the Johns Hopkins Fetal-Development Project, a 20-year endeavor that tracks how physiological aspects of the maternal-fetal bond shape development. DiPietro told me that everything from a mother’s circadian rhythms to her posture sends cues to the growing fetus...
DiPietro explains that in the future, an artificial-uterus transplant is “far, far more likely” than in-vitro gestation, in part because the placenta, which grows from the uterus after implantation, is “one of the most enigmatic organs that we have.” Scientists can’t understand it, let alone construct it from scratch. The complex interplay between the placenta—which grows from the fetus’s own cells—and the mother’s blood flow, immune system, and circulating oxygen has been so poorly researched that Alan Guttmacher, director of the National Institute of Child Health and Human Development, recently called it “the least-understood human organ.”