Sofia Vergara plans to use a surrogate to have another baby.

The 'Modern Family' actress - who has a 21-year-old son Manolo from a previous marriage to childhood sweetheart Joe Gonzalez - recently froze her eggs in the hope of having a baby with her fiance Nicholas Loeb, 37, in the future but believes she won't be able to carry the baby herself because of the treatment she received for thyroid cancer 12 years ago.

The 40-year-old Colombian star told the June issue of Cosmopolitan magazine: ''My doctor had told me, 'We have a small window.' I said, 'That's so rude!' I already have a kid, so I never thought I would need to do that.

''But I will have to use a surrogate, because I had thyroid cancer and lots of radiation. I don't want to wait forever, but not yet, because I'm working like an animal.''

The couple hope to have a child together sometime in the next five years but don't have a definite plan because Sofia is so busy and loves making money.

She said: ''I've never had a plan for anything. I know I'm not going to get any more shows like 'Modern Family'. If it ends in five years, it would be great to do movies and focus on things like my Kmart line. Maybe have a kid. But I am going to be working my whole life. I love making money. I really love it!''

The brunette beauty got engaged to entrepreneur Nicholas in July 2012 but they have no plans to tie the knot just yet.

She said: ''He was already married with a big wedding and I was already married with a big wedding, so we're going to do something but not right now.''