The blonde beauty became a first-time mother to her son Xander in September (11), but instead of taking maternity leave, Jones got straight back to work to film the fifth season of the 1960s drama.
The actress admits she struggled to find a balance between her career and her new responsibilities as a single parent, but she was able to make it work as show executives were incredibly accommodating to her needs.
She tells UsMagazine.com, ""I was back when the baby was only six or seven weeks old so it was difficult. It was difficult to be a working mum and just juggling all of that.
""But everyone made it work and it was great. They made it baby friendly for me, because I'm the first female on set to have a baby so I got to bring him. He had his own room and I was able to work around it because I was nursing.""
The tot is now seven months old and Jones reveals he's already picked up the Mad Men charm.
She says, ""He is eating solids and he is just jabbering away. He's becoming more of a little person. He is quite a charmer! I love to make him laugh. He thinks I'm funny and that's always a nice feeling.""
Jones has yet to name the father of little Xander.