Kihuen is among a growing number of lawmakers whose political careers have been thrust into uncertainty or ended altogether by allegations of sexual misconduct.
The top House Democrat, Nancy Pelosi, has called on Kihuen to resign. He has resisted that call. He also apologized after the first allegation was made public, but said he didn't remember the events the former campaign aide had described.
The committee says the mere fact that it's investigating the allegations does not indicate any violation has occurred.
The committee says it will make no further public statements pending completion of its initial review.