Do you really mean "sag" or just larger nipples? My Uni didn't get spayed until she was almost 3 yrs old, and hers are a tiny bit longer than usual, and I mean about 1/4" of an inch. Those that were spayed before or soon after their first heat are almost flat or tiny bumps with a dot on top.
I've seen puppymill breeders with huge swollen mammary glands, HUGE, that's what I would call saggy. to compare the two is quite shocking.
__________________  The T.U.B. Pack! Toto, Uni, & Bindi
RIP Lord Scrappington Montgomery McLimpybottom aka El Lenguo the Handicapped Ninja 10-12-12 
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