Testing at five to six days. It is possible that instead of removing and testing one or two cells from a two â three day old embryo, some centres may allow the embryo to develop to five - six days, when there are 100-150 cells.
Long-term use of large amounts of vitamin A might cause serious side effects including fatigue, irritability, mental changes, anorexia, stomach discomfort, nausea, vomiting, mild fever, excessive sweating, and many other side effects.
There is growing concern that taking high doses of antioxidant supplements such as vitamin A might do more harm than good. Some research shows that taking high doses of vitamin A supplements might increase the chance of death from all causes and possibly other serious side effects.