The concentration of E@ on the indicated days ( @ days , @ days , @ days after hCG injection ) in experiment group and control group were ( @ @ @ ) versus ( @@@ ) pmol/L , ( @ @ ) versus ( @ @ @ ) pmol/L , ( @ @ ) versus ( @ @ ) pmol/L ; the concentration of VEGF on the indicated days in the two groups were ( @ ) versus ( @ ) ng/L , ( @ ) versus ( @ ) ng/L , ( @ ) versus ( @ ) ng/L ; the concentration of E@ and VEGF were lower than those in control group ( all P < @ ) .