Multiple pregnancies have very serious implications for the mother and her offspring, for the family and the community, and for health service resources. In vitro fertilization increases the risk of multiple pregnancies anytime more than two embryos are transferred into the uterus. Children born after in vitro. Fertilization has a 3.7 risk of developing cerebral palsy compared to singletons, mostly because of premature birth and low birth weight linked to multiple pregnancies. Therefore, it is strongly recommended to prevent multiple pregnancies in patients treated by induction of ovulation. Only one single embryo, at most two embryos, be transferred during IVF in order to limit the risk of neurological sequel in the offspring. Obstetrician-gynecologists have an important responsibility to make both the public as well as their patients aware of the many hazards associated with multiple pregnancies. Besides general considerations on the consequences of multiple pregnancy like (twin to twin transfusion syndrome, fetal structural and chromosomal malformations, twin to twin conflict, and conjoined twins fetal reduction) which lead to specific ethical issues which are discussed in the present chapter.