Appeal by the defendant from a judgment of the Supreme Court, Kings County (J. Goldberg, J.), rendered June 9, 1999, convicting him of sexual abuse in the first degree (three counts) and endangering the welfare of a child (three counts), upon a jury verdict, and imposing sentence.
Ordered that the judgment is affirmed.
The defendant’s contention that the testimony of the People’s expert on the subject of Intrafamilial Child Sex Abuse Syndrome improperly bolstered the complainants’ testimony and deprived him of due process and a fair trial is unpreserved for appellate review, as he did not object on these grounds before the trial court (see CPL 470.05 [2]; People v Ocean, 292 AD2d 545, 546 [2002]; People v Naranjo, 194 AD2d 747, 748 [1993]). In any event, there is no merit to the defendant’s contention, as the testimony helped explain the complainants’ behavior after the *907abuse, which was not within the purview of the average juror (see People v Carroll, 95 NY2d 375, 387 [2000]; People v Taylor, 75 NY2d 277, 288 [1990]; People v Keindl, 68 NY2d 410, 422 [1986]; People v Hinspeter, 12 AD3d 617, 618 [2004]; People v Brown, 7 AD3d 726, 727 [2004]; People v Lopez, 187 AD2d 533, 534 [1992]).
The defendant’s remaining contention is without merit (see People v Taylor, 1 NY3d 174, 176 [2003]; People v Tonge, 93 NY2d 838, 840 [1999]; People v McFarlane, 18 AD3d 577 [2005]). Schmidt, J.P., S. Miller, Santucci and Skelos, JJ., concur.