Dr. Drew Pinsky is speaking out about 'Teen Mom 2' star Leah Messer in light of recent reports that the 23-year-old reality TV star has lost primary custody of her five-year-old twins, Ali and Aleeah.

"I was expecting progress," Dr. Drew, who has moderated multiple 'Teen Mom' reunion specials, said in an exclusive interview backstage Thursday at the Rachael Ray show.

"If you saw the last reunion show -- which is the last time I had contact with her -- I believed she was making some progress," he said.

"One of the signs I noticed was that the people around her -- like her ex-husband and his new wife -- people around her were starting to really come down on her," he continued. "When that starts to happen, that's a sign to me that the identified patient is getting better."

Dr. Drew ultimately told Messer -- who has struggled with depression, anxiety and accusations of drug use -- that this was a "good sign." Messer has denied having a drug problem.

"I told Leah that I thought that was a good sign, and that she should just learn to tolerate it," Dr. Drew said. "This is when they're really going to come down on her, but to just focus on her treatment. Which she was willing to do. She had lots of good questions for me.

"I don't know if this recent issue with the child custody is going to set her back, but I certainly wish her the best," he added. "She is working very hard and this has been a terribly painful and stressful time for her. So, let's all wish her the best."

Messer has a third child with her second ex-husband, Jeremy Calvert.

The story was first reported by InTouch Weekly.