“…In October 2015, China introduced the two-child policy [ 14 ], which over time led to increases in the number of women of advanced maternal age; women who had undergone caesarean sections or had uterine scars; women who used assisted reproductive technology, and women who had multiple pregnancies [ 15 – 18 ]. Previous studies have shown that these factors might increase the risk of adverse pregnancy complications, including placenta previa [ 19 – 23 ].…”