Jaime Pressly has announced she is pregnant with twin boys.

The 39-year-old actress is expecting two babies with her long-term boyfriend Hamzi Hijazi, 38, and she admits she was shocked when she was told that she was going to be a mother twice over.

Speaking exclusively to this week's issue of People magazine, she said: ''Twins don't run on either side of our families so we were completely shocked. This wasn't IVF or anything like that. It was just a shock, and I'm like, 'Doctor, that's impossible!' ''

The 'Mom' star also revealed that she and Hijazi had been trying ''for quite a while'' to start a family together and now she's getting two tots she feels as though ''God cutting me some slack''.

Jaime readily admits she was getting worried her biological clock was ticking down as she approaches 40 and she couldn't be happier to be adding to her family.

The blonde beauty - who already has 10-year-old son Dezi James with her ex-partner Eric Calvo - added: ''I've always wanted three kids and the older I'm getting, I'm like, 'OK, maybe just one more would be nice.' I was getting a little sad, but it was like, 'We'll give you two in one. You don't have to do another pregnancy.' ''

Jaime's son Dezi is very excited to meet his younger siblings and get the chance to be a big brother.

He said: ''He's been begging Hamzi and I to give him a sibling since he was in kindergarten. He's very patient and sweet and gentle and is going to be the best little babysitter ever. He's constantly kissing my belly ... I'm 10 years older than I was the last time [I was pregnant], so the pregnancy is completely different. They've been doing like, river dance on my uterus! I'm excited to do this 10 years later when I'm older and wiser and more calm. It's going to be a totally different experience, but a great one. I'm so excited for it!''