Actor Tom Arnold is to become a first-time dad at the age of 53.

The True Lies star and his fourth wife, Ashley Groussman, will welcome a son this March (13) - and the comedian can't contain his excitement.

Announcing the happy news during a guest co-hosting stint on talk show The View on Friday (18Jan13), he joked, "I'm pregnant. I have put on, like, 40 pounds. My wife is pregnant too. We're having a baby. It's seven months (along) and it's a boy and it's my first baby."

Arnold, who suffers from a low sperm count, previously revealed he and his wife have been trying to start a family since they married in 2009, and they consulted fertility doctors in 2011 in their bid to conceive.

The in vitro fertilisation treatment has been a success and the veteran star admits the unborn baby is his "miracle" child after yearning for years to become a father.

He added, "We're really happy, I just can't believe it. I didn't think it'll be on the cards for me, it is a miracle, so it is a complete shock."

Arnold counts funnywoman Roseanne Barr among his ex-wives.