1 Introduction
The development and functions of the human placenta affect the fetus and, consequently, influence indicators of fetal health such as birth weight and growth [1], prematurity [2], and neuro-development [3]. There is also evidence that assessment of the placenta facilitates predictions of future health problems in adulthood [4]. This vital but barely studied organ controls the transmission of nutrients and hormones from the maternal to the fetal circulatory system and is essential for the fetal immune defense.