In pigs where you have multiplebirths, you could have crowding or some other issue that creates the defect [later on].
猪是多胞胎，它们可能会相互拥挤或者有其他的一些问题，造成了这些缺陷。
2
Multiplebirths were excluded because even naturally conceived multiples have a high risk of complications, Romundstad says.
多胎生产被排除了，因为甚至在自然状态下，怀三胞胎也有很高的患并发症的风险。
3
And while multiplebirths represent one of the great wonders of life in their own right, they provide important clues in the mysterious case of nature versus nurture.