Simplicity 9176 vintage sewing pattern, dated 1971.

Maternity mini-dress with detachable collars and cuffs and pants in misses' sizes.

The dress with back zipper has high round neckline and long or short set-in sleeves. The contrasting detachable collars V. 1, 2, 3 & 4 has band. V. 1 features "Peter-Pan" collar, detachable cuffs, button trimmed tab and top-stitching or lace edging trim. Button trimmed V. 2 has "Dog Ear" type collar. V. 3 has "sailor" collar with ribbon trim. V. 4 features collar and detachable cuffs of lace edging. The pants have elastic waistline casing and stay of jersey. 

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 has spotting, and a tear at opening corner.

More vintage maternity patterns here:

http://allthepreciousthings.com/collections/maternity