Compared with recipients of oral placebo ( n = 62 ) , girls who received childhood low-dose EE2 ( n = 61 ) had significantly earlier thelarche ( median , 11.6 vs 12.6 y , P < 0.001 ) and slower tempo of puberty ( median , 3.3 vs 2.2 y , P = 0.003 ) ; both groups had delayed menarche ( median , 15.0 y ) .