As of 2015, the primary cause of preeclampsia remains unidentified, notes the Preeclampsia Foundation. However, the onset of this condition is associated with dietary and hereditary factors, autoimmune disorders and vascular problems.
Preeclampsia is a medical condition that develops in pregnant women, typically occurring during the late stages of the second trimester. It is characterized by increased blood pressure and elevated levels of protein in the urine. Although the definitive cause of preeclampsia continues to baffle medical specialists, there is consensus among scientific experts that improper placental formation of new vascular structures may cause preeclampsia.
A fetus derives its nutritional needs through the placenta, which forms a link between the mother and unborn baby. Insufficient blood flow to this temporary organ triggers a release of certain chemicals, which in turn leads to the excessive production of factors that control blood vessel constriction, states the United States' National Institutes of Health. This eventually results in hypertension and kidney-related problems that are normally associated with preeclampsia.
Preexisting disorders and illnesses are also possible causes of preeclampsia. These medical conditions include lupus, diabetes, hyperthyroidism, renal disorders and sickle cell disease. Expectant mothers who are not getting adequate nourishment from their diets may also suffer from preeclampsia. Other leading theories regarding the etiology of preeclampsia include obesity, hormonal imbalance and abnormal inflammatory reaction to pregnancy. A history of preeclampsia in the family may also cause succeeding generations to develop the condition. However, the manner in which preeclampsia may be transmitted to family members is still largely unknown.