This is not a full pattern or tutorial for making a nursing hoodie. It's only the first couple steps on how to alter an existing pattern.
You will need a hoodie pattern
Enough fabric for your size according to your pattern
Your fabric needs to have some stretch
*update: I made a second one using 2 fabrics with 4 way stretch. The purple is cotton Lycra. I forget what the floral is but it also has 4 way stretch and is a bit thinner and softer than the purple. It was "flawed" fabric from girl charlee I got for $2 a yard!!! If you order from Girl Charlee too be sure to use coupon code 42716 to save 10%.
So here are a couple better pictures I took with a quick overview. More detailed instructions follow with my black micro fleece hoodie.
Basically you need a hoodie pattern. All you need to do is cut one extra front piece and cut that piece down the middle. Now take the full front piece and fold over the sides a few inches or measure where the pocket will go and fold over to that point and stretch stitch down both sides. Place the 2 separate front pieces down and carefully line up the full front piece over that. Pin in place and baste stitch over the arms and neckline. Now place your pocket in the spot your pattern shows and sew that on over both layers. Continue with your pattern's directions.
Cut out your pattern. Instead of one front piece cut two. The second piece you will cut down the middle from top to bottom. With the uncut piece fold over the ends a few inches and pin. Update: the only thing I would change about this step is fold the front piece over enough so that the edge meets up with where the pocket will go. I haven't tried it this way I just think the sweatshirt might function a bit better.
Now top stich where you pinned using a stretch stitch.
Next, carefully lay the uncut piece over the cut pieces. Line them up and pin at the shoulders. Optional also pin at the collar.
Sew or serge as close to the edge as possible at the shoulders and optional at the collar. Make sure both pieces line up as you sew.
Again, making sure top and bottom pieces are lined up pin the pocket in place. You will be sewing it on both layers of fabric. Follow your pattern's directions for how to sew your pocket.
To finish your sweatshirt follow your pattern's instructions. This is what mine looks like finished.
And one to show where the side opens. I placed the scissors where you will pull the two front pieces apart for nursing access.