Mariah Carey and Nick Cannon with their twins and Barbara Walters. (Donna Svennevik/ABC)

Mariah Carey and Nick Cannon are now the proud parents of twins, Monroe and Moroccan. But getting to this point was difficult, the couple tell Barbara Walters in an interview airing Friday.

The 41-year-old singer told Walters she used acupuncture combined with fertility treatments to conceive after suffering from a miscarriage.

“The main thing I did that was tough, was to go on progesterone like every month … and then when I was pregnant, I had to stay with the progesterone for 10 weeks,” Carey said. “It minimizes the chance of miscarriage by 50 percent.”

The couple now have six-month-old “little geniuses,” as Cannon calls them.

As for the allegations that Carey drank beer after giving birth to stimulate lactation, which led to a visit from a social worker, she said, “It just doesn’t make any sense. ... I didn’t even drink the beer.”

The full interview, which includes Roc and Roe’s TV debut, airs Friday on “20/20” at 10 p.m. Watch previews clips below.