Guo, Xiao, Feng Wang, Jing Li, Zhankun Guo, and Jing Wang. “Prediction Performance of Serum Placental Growth Factor (PLGF) Human Chorionic Gonadotropin β (β-HCG) and PAPP-A Levels in Early Pregnancy for Pregnancy Outcomes”. Pakistan Journal of Medical Sciences 38, no. 7 (August 30, 2022). Accessed April 18, 2024. https://pjms.org.pk/index.php/pjms/article/view/5248.