Chromosome balanced translocation is divided into two types: reciprocal translocation and Robertson translocation. It is the most common chromosome structural abnormality in humans, and the incidence rate in the population is 1/‰-3‰. Carriers of balanced translocation usually have normal intelligence and phenotype, but their child will face the same serious problems such as spontaneous abortion, stillbirth, and fetal malformations. For balanced translocation carriers, the most suitable method of birth is with the help of preimplantation genetic diagnosis technology (PGD). Conventional PGD assist balanced translocation carriers to realize successful childbirth, however it cannot distinguish between a completely normal embryo and a balanced translocation carrying embryo. This means that the offspring has a 50% probability of being a balanced translocation carrier and facing the same infertility problems as his parents when he grows up.