True regarding maternal plasma osmolality during pregnancy
Increased water retention in pregnancy is normal physiological change of pregnancy. It is mediated by fall in plasma osmolality induced by resetting osmotic thresholds for thirst and vasopressin secretion.
Maternal plasma osmolality decreases early in pregnancy
Maternal plasma osmolality increases throughout pregnancy
Maternal plasma osmolality does not change during pregnancy
Maternal plasma osmolality is affected most by increases in sodium