Is maternal alkalosis harmful to the fetus?

Normal pregnancy is characterized by a compensated respiratory alkalosis. The effect of maternal alkalosis on the fetus is less well understood than the more common problem of maternal acidosis. We present a case of maternal alkalosis, complicated by bronchial asthma, in which the fetus was stillborn. The pathophysiology of this condition is discussed with data to support the potential harm of maternal alkalosis in pregnancies complicated by a fetus with borderline reserve. In such instances, the fetus should be carefully monitored and consideration might be given to therapy such as the use of acetozolomide, discouraging hyperventilation by the mother and even early delivery of the fetus.