We all know what “IVF” is, and we may have heard that there are different kinds of IVF, first generation, second generation, and third generation IVF, so is third generation IVF necessarily better than first generation IVF? Let’s first understand the basic process of each generation of IVF. The first generation of IVF, also known as “in vitro fertilization-embryo transfer”, is the earliest IVF technology to emerge. The essence of IVF is to remove the woman’s eggs and the man’s sperm separately, put them in a culture and let them fertilize naturally to form embryos for transfer. Ovulation disorders, tubal obstruction or adhesions, endometriosis, low ovarian function, unexplained infertility in the female partner, severe oligospermia in the male partner, and infertility due to both partners are all indications for first generation IVF. Sometimes, however, the eggs are placed in a culture containing sperm and it is found that they do not fertilize properly. What to do? Clever researchers have come up with another solution, which is to inject a single sperm into the eggs and artificially help them to fertilize. This is called second generation IVF, also known as intracytoplasmic single sperm injection. So when there is a fertilization disorder, or when the male partner has very severe oligospermia that prevents first generation IVF, an embryologist is needed to perform this delicate procedure. There are also times when couples who can conceive naturally have troubles: when they are older, have recurrent embryonic stoppages or spontaneous miscarriages, or carry abnormal chromosomes and are at risk of miscarriage or genetic disease. At this point, geneticists may recommend that they consider third-generation IVF treatment, also known as pre-implantation genetic diagnosis. This involves removing one or several cells from multiple embryos, performing chromosomal or even certain genetic diagnostics, discarding embryos with chromosomal or genetic abnormalities, and transferring normal embryos so that the couple can have a healthy baby. Therefore, when you are older, have recurrent embryonic stoppages or spontaneous miscarriages suspected to be chromosomal or genetic related, or when one of the couple carries abnormal chromosomes or genes, you may consider the third generation of IVF treatment. As you can see, each generation of IVF has its own characteristics and range of treatment, and it is not the higher the level that is better!