Pregnant women or those hoping to start or extend a family should avoid using the cholesterol-lowering drugs statins, say scientists.
Current clinical guidelines already recommend that women who are pregnant should stop taking statins but the advice is based on the knowledge that cholesterol is essential for normal fetal development.
Indeed, a 2007 study examining the risk of congenital anomalies in children of pregnant women using statins suggested that the detrimental effects of the drugs may be restricted to fat-soluble or 'lipophilic' statins only.
But new research from The University of Manchester has shown that even water-soluble or 'hydrophilic' statins, such as pravastatin, can affect placental development leading to worse pregnancy outcomes.
"The rapid rise in obesity and type-2 diabetes is a major health issue and affected individuals are often treated with statins to lower circulating cholesterol levels and reduce the risk of heart disease," said Dr Melissa Westwood, a Senior Lecturer in Endocrinology based at the Maternal and Fetal Health Research Centre at St Mary's Hospital, Manchester.
"Given the evolving demographic profile of these conditions, such drugs are increasingly prescribed to women of reproductive age but the actions of statins are not limited to the regulation of cholesterol levels, as they can affect the production of other chemicals in the body too.
"Our study examined the effects that both lipophilic and hydrophilic statins had on a key biological system that is crucial for maintaining the normal function of the placenta, which acts as the nutrient-waste exchange barrier between mother and fetus."
The research, funded by the Biotechnology and Biological Sciences Research Council (BBSRC), used a placental-tissue model that could be maintained in a viable state outside the body for several days and tested the effects of two different statins - one water-soluble and one that dissolves in fat.