Simplicity 7100 vintage sewing pattern, dated 1976.  

Maternity Short Jumper or Top and Pants in Misses' Sizes:

The short jumper or top with "cut-out" armholes has back zipper and low round neckline. The jumper with armhole ruffles has patch pockets with bands and ruffles. The top has top-stitching trim. The pants with elastic waistline casing have pants stay of cotton or nylon stretch jersey or a maternity stretch panel may be used. 

Size   12.

Bust   34 Inches / 87 cm

Waist 26.5 inches / 67 cm

Hip    36 inches / 92 cm

Pattern is partly cut and checked complete. Envelope is in good vintage condition, with some wear around opening.

More '70s patterns here:

http://allthepreciousthings.com/collections/1970s