While the effect of IGF on the ovaries likely involves fraternal, or dizygotic, twins, they were not distinguished from identical, or monozygotic, pregnancies in this study.

• 在本研究中，虽然IGF作用于卵巢可以引起异卵或双合子双胞胎妊娠，但是这种妊娠不能和同卵或单合子双胞胎妊娠相区别。