According to a study published on bmj.com, the second born twin has a greater risk of serious complications during delivery. This study also states that there is no big difference in overall death ratio for preterm born twins. But the second twin born at or after the complete term of pregnancy was more likely to die during the labor or shortly after birth.
Many studies have talked about the risk factor associated with the second born twin. But some studies dismiss the relevance of birth order in the survival of the second twin. To shed more light on this area, British scientists have conducted an exhaustive study on twin mortalities.
The data were obtained from Confidential Enquiry into Maternal and Child Health (CEMACH), the Confidential Enquiry into Stillbirths and Deaths in Infancy (CESDI) and Office for National Statistics (ONS). The data about 1377 twin pregnancies were thoroughly analyzed.
Other factors like the duration of gestation, methods of delivery, mother's age, race, the association between birth order and risk of death were extensively studied. In the end, it was concluded that complications arising during the delivery may increase the death risk for the second twin. This could be avoided if a C section was performed. On the other hand, the race or the age of the mother, or birth order did not have any effect on the risk of death among pre term twins.