The reason that pre-eclampsia can be characterized
as ill-defined, lies in the fact that the commonly employed
criteria for setting the diagnosis are elevated
blood pressure after week 20 combined with proteinuria.
But both blood pressure and protein levels fluctuate,
and it is probable that many cases, especially those
occurring in the last part of pregnancy, go undetected,
since hypertension and proteinuria may not be present
at the same antenatal visit. Some investigators have
proposed that pre-eclampsia is only the tip of the
iceberg, i.e. that pregnancy represents a heightened
state of inflammation that can vary from person to
person [3]. For each woman, the presence of overt disease
will depend on the length of gestation as well as
characteristics such as body mass index (BMI), parity,
prior pregnancy outcomes, diabetes and multifetal
pregnancy, to name a few that are considered wellestablished
risk factors for pre-eclampsia. The heterogeneous
nature of the disorder has led to some pessimism
as to the possibility to find etiological factors
with large effects.