Population: births from twins in Milan

The dataset contains the historical series (from 1979 onwards) of the simple and trigeminal twin parts (or of higher order) and the incidence of the multiple parts on the total of the parts. The events refer to the present population.本数据集收录了1979年起的历史时序数据，涵盖单胎与三叉双胎（或更高阶多胎）的相关组分，以及多胎组分占总组分的发生率。本数据集所涉及的研究事件均针对当前研究人群。