Sampling the Human Placenta

Comparison of Human and Rodent Fetal-Maternal Blood Barriers 

The site of transfer of nutrients from mother to fetus is the fetal-maternal blood barrier. There is somewhat of an analogy between this interface and the blood-brain barrier in the central nervous system. Both must provide mechanisms for transfer of essential nutrients yet provide some protection against transfer of toxic substances. In mammalian systems the interface between maternal and fetal blood is located in the chorionic villus. There 

The mechanism for the transport of lead through the placenta is not well defined. There are several reasons for suggesting it may be a matter of simple diffusion from maternal to fetal circulation (Goyer 1990). For one, 

Maternal Blood Lead Levels During Pregnancy 

Maternal blood lead levels and umbilical cord blood lead levels are the most direct measure of fetal exposure to lead, reflecting recent lead exposure and lead mobilized from tissue stores (Mushak 1989). Recent studies of mobilized 

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