How long before I ought to end sleeping on my back? I am 10w3d.

Sally • Hippie Mama, Crunchy in the most extreme ways. Gardening, vegan, organic living. Extended Breastfeeding my son and daughter in tandem. Baby wearing. Home cooking. Goth mamma.
It is how I sleep best. The only time I sleep on my side is while my son is latched on (he is 22 months). Then, when he rolls back over, I roll on my back...automatically.