Is maternal anemia associated with small placental volume in the first trimester?

To clarify whether maternal anemia could reduce placental volume in the early gestation.

A prospective cross-sectional study was conducted. Consecutive women who visited at 11-13 + 6 weeks' gestation were enrolled. Subjects were divided into two groups by maternal hemoglobin concentration. Cases with maternal anemia were defined as a hemoglobin level less than 11 g/dl on a blood test (cases), and the others were defined as controls. An ultrasound examination was performed to measure the placental volume and the uterine arterial blood flow. The three-dimensional volume of the placenta using virtual organ computer-aided analysis (VOCAL) technique was acquired by transabdominal ultrasonography. Placental volumes were compared in women with and without anemia.

31 cases and 486 controls were analyzed. Maternal characteristics were not different between two groups except anemia. Placental volumes were 63.6 ± 22.2 and 60.9 ± 22.8 cm(3) (ns), uterine arterial RIs were 0.7 ± 0.1 and 0.8 ± 0.1 (ns), and PIs were 1.7 ± 0.5 and 1.8 ± 0.6 (ns) in cases and controls, respectively.

Maternal anemia was not associated with reduced placental volume and uterine arterial Doppler wave form at 11-13 weeks' gestation.