Illustration of a section through a female pelvis showing complete placenta previa, where the placenta lies across the cervix (neck of the womb), totally obstructing it. The foetus is at full term and is in the birthing position. The placenta is a temporary organ that connects a developing foetus to its mother. The placenta carries oxygen and nutrients to the foetus and removes waste products. A vaginal delivery with placenta previa often results in life-threatening blood loss to the mother and baby. In modern times the baby would be delivered by caesarean section. From An Improved System of Midwifery, by Wooster Beach (1794-1868), published in 1851.