Provided herein is a pre-Caesarean method for collecting amniotic fluid from a patient. A needle is inserted into the incision site for the future C-section, which may be under ultrasound guidance, through which the amniotic fluid is drawn under a low level suction and, optionally, gravity to a sterile collection container. The method encompasses filtering and/or irradiating the amniotic fluid to collect biomolecules of interest such as growth factors and/or stem cells. Also provided is the sterile amniotic fluid or filtrates thereof collected by the method described herein.