Scientists Grow Artificial Embryo Models Without Sperm, Egg, or Womb

Scientists have cultivated something resembling a human embryo without using sperm, eggs, or a womb. A research team from the Weizmann Institute of Science in Israel has created complete models of human embryos from lab-grown stem cells and has grown them outside the womb until day fourteen. The results of this experiment, published in the journal 'Nature', show that the artificial embryo models possess all the structures and characteristics necessary for their growth at this stage. Cell masses derived from human stem cells in previous studies cannot be considered true human embryo models as they lacked almost all the defining characteristics of an embryo, such as several types of cells essential for embryo growth. Additionally, they did not have the structural features of an embryo and did not show the ability to progress to the next growth stage. This embryonic model was created using stem cells and, according to the design team, resembles a textbook example of a real 14-day-old embryo. Scientists mixed human stem cells, which can differentiate into various cell types, and found that about one percent transformed into 'complete' embryo-like structures. These newly created model embryos are equivalent to one-week-old human embryos and were cultured in the lab for another week; however, due to the age of the embryos and the fact that they bypassed the stage necessary for implantation into the uterine wall, it is biologically impossible to place them in a womb for pregnancy. While the small structures of the model embryos are not identical to human embryos, researchers hope that the models can help illuminate the mysteries of the early stages of human embryo development and the unknown causes of miscarriage. Dr. Jacob Hanna, the lead researcher, states that the biggest challenge lies in the first month of embryo formation and architecture, which is essentially the black box of pregnancy issues, with the embryo primarily growing in the remaining eight months. Understanding early embryo growth is just one application of artificial embryo models. Another scenario Dr. Hanna described in an interview with The Guardian is the creation of model embryos from the skin cells of sick individuals. He mentions that model embryos can be grown for a month or more and then start developing organs that could serve as a cellular source for transplantation to patients. Another application scientists have in mind is using model embryos to assess the potential effects of drugs on real human embryos. Since pregnant women are often excluded from clinical trials, doctors are uncertain about the side effects of some of the most common drugs and treatments on pregnant women and newborns. While the growth of embryo models up to this stage is legal due to their distinction from real embryos, continuing to grow the embryos beyond this point raises ethical and medical concerns that need to be addressed.