Simplicity 8855 vintage sewing pattern, dated 1970.

Maternity Pants in Two Lengths, Dress or Tunic in Misses' Sizes:

The dress V. 1, 2 and 5 and the tunic V. 3 and 4 with front zipper closing have lowered round neckline. V. 1 and 2 have optional patch pockets, top-stitching, button trim and purchased scarf. V. 1, 2 and 3 have collar and short set-in sleeves. V. 3 features contrasting collar. V. 4 with button trimmed patch pockets has braid trim. V. 4 and 5 are collarless. V. 5 with set-in puff sleeves gathered to sleeve bands have embroidered eyelet edging trim and ribbon tie belt. The maternity long pants V. 3 and the short pants V. 3 with elastic waistline casing have front stay of jersey or purchased stretch panel. 

Size  12:

Bust  34 inches / 86 cm

Waist 26 1/2 inches / 67 cm

Hips  36 inches / 91 cm

Pattern is partly cut and checked complete. Pattern envelope is in good vintage condition, with a name handwritten on the front.

More vintage maternity patterns here:

http://allthepreciousthings.com/collections/maternity