It is well known that conventional antihypertensive agents are not effective for
severe preeclamsia patients. However intra-uterine fetal death or interruption
of pregnancy by Cesarean section results in the decrease of blood pressure
of severe preeclamsia patients. Therefore obstetricians decide Cesarean
section irrespective of pregnancy weeks even if fetus is premature.
Fetal oxygen is supplied from placenta. It is well known that fetus is exposed Fetal blood pressure is much lower than mother in addition blood pressure of When conventional antihypertensive agents are administered to preeclamsia If obstetricians consider the physiology of pregnancy above mentioned,
to hypoxia and fetus increases angiotensin and vasopressin, both of them is
powerful vasoactive peptide hormone, in parallel with hypoxia in preeclampsia,
suggesting that fetus makes an effort to increase blood pressure in the
feto-placental unit. Placenta is essential organ of feto-placental unit.
Placenta is attached maternal site to uterus and fetal oxygen is supplied from
maternal blood, the space between placenta and uterus (so called retro-placental
blood pool).
placental peripheral circulation is much more low than mother.
patients, these agents easily move to the feto-placental unit and then they block
the fetal action to hypoxia, namely an effort to increase blood pressure.
they hesitate to use conventional antihypertensive agents to severe
preeclamsia patients.