Hanoi Medical University, Hanoi Medical University - Department of Obstetrics and Gynaecology, Hanoi Medical University - Department of Outpatient, Hanoi Medical University - Deparment of Delivery, Hanoi Medical University - Department of High risk Pregnancy, Hanoi Medical University - Department of High risk Pregnancy, Umeå University - Oncology, Hanoi Medical University - Department of Gynecogy and University of Paris - Department of Obstetrics, Fetal Medicine and Surgery