The mevalonate pathway synthesizes intermediates and products such as 
cholesterol and nonsterol isoprenoids that are crucial for cell survival and 
function. In the human placenta, the prenylation of proteins, rather than 
cholesterol synthesis, represents the main "metabolic target" of mevalonate 
metabolism. Major cellular functions depend on isoprenylation including 
proliferation, migration, metabolism and protein glycosylation that are all 
crucial for proper development of the embryo and the placenta. Statins are 
inhibitors of HMG-CoA reductase, the enzyme that catalyzes the reduction of 
HMG-CoA to mevalonic acid by NADPH. In vitro experiments using human placental 
explants suggest that statins elicit a detrimental effect on placental growth. 
However, animal and epidemiologic studies show no increase of fetal 
malformations after exposure to statins during pregnancy. Moreover, emerging 
evidence from mouse studies suggest that statins may be useful in preventing 
serious pregnancy complications like preeclampsia.