Non-invasive hemoglobin monitoring will be performed in patients who underwent cesarean section with placenta previa and this will be compared with actual laboratory findings.

The investigators will investigate whether noninvasive hemoglobin monitoring can adequately reflect the massive bleeding that occurs within a short period of time and find out if it matches the actual laboratory findings.

Inclusion Criteria:

• Pregnant woman
• Elective Cesarean section
• Placenta previa

Exclusion Criteria:

• Decline of consent
• Peripheral vascular disease
• Cyanosis due to congenital heart disease
• Refusal of transfusion
• Mental retardation