Expressiong of egfr in placenta in the first trimester was significantly stronger than that in placenta of the second and third trimesters ( p < 0 . 01 ) . the related quantity of egfrmrna expression in the placenta in the first trimester was significantly stronger than that in placenta of the second and third trimesters ( p < 0 . 01 ) 整个妊娠过程中egfr的表达量孕早期高子孕中期、晚期,结果有显著性差异巾0刀1 ) 。 ;妊娠早期egfrmrna的表达明显强于中期和晚期一0 01 ) ,中期较晚期的表达明显增加一0