Thousands praised the photo for giving women with all different bumps confidence, but also met some criticism with people asking whether Duncan - who is now a high-intensity interval trainer - should be doing so much exercise while pregnant.
Duncan said at the time:
Each woman carries different and this most certainly doesn't mean one is doing something wrong or not healthy etc. We both have healthy growing babies and we both have had incredible pregnancies so far, feeling amazing and full of energy.
Now, the women have both given birth, and in case you were wondering, Chontel's son Jeremiah Thomas Duncan was born on Friday weighing in at 7’13 pounds.