Report on a consecutive series of 581 children born after blastomere biopsy for preimplantation genetic diagnosis

BACKGROUND: Preimplantation genetic diagnosis (PGD) and subsequently preimplantation genetic screening (PGS) have been introduced since 1990. The difference from the already existing in vitro fertilization (IVF) technology, using intracytoplasmic sperm injection (ICSI), was the embryo biopsy at day 3 after fertilization. Although healthy children post-PGD/PGS have been born, the question of whether embryo biopsy could have any harmful effects has to be studied on large series in a prospective manner.

METHODS: A prospective cohort study was undertaken from 1992 until 2005, using the same approach as for the follow-up of IVF and ICSI children conceived in the same centre. Questionnaires were sent to physicians and parents at conception and at delivery. Children were examined at 2 months of age by trained clinical geneticists whenever possible.

RESULTS: Data collected on 581 post-PGD/PGS children showed that term, birthweight and major malformation rates were not statistically different from that of 2889 ICSI children, with overall rates of major malformation among these post-PGD/PGS and ICSI children being 2.13 and 3.38%, respectively (odds ratio [OR]: 0.62; exact 95% confidence limits [95% CL]: 0.31-1.15). However, the overall perinatal death rate was significantly higher among post-PGD/PGS children compared with ICSI children (4.64 versus 1.87%; OR: 2.56; 95% CL: 1.54-4.18). When stratified for multiple births, perinatal death rates among PGD/PGS singleton and ICSI singleton children were similar (1.03 versus 1.30%; OR: 0.83; 95% CL: 0.28-2.44), but significantly more perinatal deaths were seen in post-PGD/PGS multiple pregnancies compared with ICSI multiple pregnancies (11.73 versus 2.54%; OR: 5.09; 95% CL: 2.80-9.90). The overall misdiagnosis rate was below 1%.

CONCLUSIONS: Embryo biopsy does not add risk factors to the health of singleton children born after PGD or PGS. The perinatal death rate in multiple pregnancies is such that both caution and long-term follow-up are required.