Increase in premature births, low birth weight, congenital abnormalities and perinatal complications…
There is growing medical evidence of the presence adverse outcomes following the use of assisted reproduction techniques. There is no doubt that most perinatal morbidity associated with in-vitro fertilization (IVF) can be attributed to multiple pregnancies.
The latest data from the United States shows that the incidence of twin pregnancies after in vitro fertilization is 29%, and for triplet pregnancies is 3.7%, 14 and 57 times higher, respectively, than those that occur in natural conception. It is widely agreed that multiple pregnancies have much higher risks than singleton pregnancies. For example, more than 60% of twins are born prematurely, and 50% have low birth weight, when these percentages are 14% and 9%, respectively, in singleton pregnancies, i.e. it seems obvious that the negative side effects associated with multiple pregnancies are increased by the use of assisted reproduction.
However, the adverse effects are not limited to multiple pregnancies. Although most singleton pregnancies that result from in vitro fetilization are uncomplicated, various studies indicate that they are associated with an increase in premature births, low birth weight, congenital abnormalities and perinatal complications, when compared with naturally-conceived singleton pregnancies. These data were evaluated in detail in a study published in Fertility and Sterility (95; 1887-1889, 2011), confirming that described above on the existence of an increase in negative effects associated with assisted procreation.