The full name of what we all usually call IVF should be In Vitro Fertilization – Embryo Transfer (IVF-ET). To put it simply, a fine needle is used to aspirate the egg from the mother-to-be’s ovary, and the father-to-be’s sperm is removed, processed and combined with the egg in a laboratory dish to form a fertilized egg. The fertilized egg is then transferred back into the mother’s uterus using a very thin catheter. In the first generation of IVF, the sperm and egg are added to the same culture medium and incubated together. The sperm will naturally burrow into the egg, thus fertilizing it, and the fertilization process occurs naturally, similar to the fertilization process in a natural state of pregnancy. Second generation IVF, which we call intracytoplasmic single sperm injection (ICSI), is performed under an inverted microscope using a special device to grab a sperm while holding an egg in place, and then inject the sperm into the egg cell with precision to force the fertilization process, hence the name intracytoplasmic single sperm injection. Second generation IVF is mainly applied to men with severe oligospermia, meaning that the male partner’s sperm is too few or too weak in vitality to allow normal fertilization of the egg in its natural state, so we use single sperm injection to inject sperm directly into the egg to force fertilization. Thus, second generation IVF ensures normal fertilization of the eggs and makes the success rate of IVF much higher.