Rather than selecting for the traditional pregnancy wardrobe of empire line dresses in various lengths and colours, January donned a draped asymmetrical dress with lace web detailing from the Doo.Ri Fall 2011 collection.
Rosegold 'Layla' sandals, a gold watch and a casual updo kept the look light enough for springtime.
The actress was on the NBC programme with her fellow X Men: First Class castmates (try saying that three times in a hurry!) to promote the movie.
Let us know what you think of January's maternity wear in the comments below.