This times infinity. It’s actually really disgusting how there can’t be a single thread about anything to do with women without male Dopers coming in and begging for ERMERGERD PICS!!! or TEEHEEHEE LET ME BE YOUR BRA HYUCK HYUCK HYUCK :p;):D;):p;):D:). Ugh.
Anyway, OP, I wish I had an answer for you, but I’ve actually heard of similar stuff from various friends. My best guess is a weak “hormonal changes,” but I know that doesn’t do much help.
I hear what you’re saying.
You want the Champion Powerback Underwire Sports Bra. It is pricey but if you’re a C up or above you absolutely need one high impact sports bra specifically built for large breasted women. And yes, it IS a hassle. I’m of “the age” where it’s thought to be nice but it makes shopping quite literally a hellish experience.
I recommend washing in a mesh laundry bag and hanging dry or washing by hand separately and hanging dry. DON’T wash with other clothes or it will twist and stretch and DON’T PUT IT IN THE DRYER. 
–lindsaybluth, formerly 36D now 34DD
Do you live near a source of radiation?
As a hetero male who loves boobs, I approve of this post.
(ETA: and don’t bother with the username/post combo thing)
Maybe. it is the same thing that happened to Joyce Gibson ? http://www.boobpedia.com/boobs/Joyce_Gibson
Oh my gosh! Having the same problem.
I have always been really thin and ALWAYS An A cup I would go into La Vien Rose and say" I’ll take everything in a push up cup in a 34 A please give me some cleavage! Well not any more… i’m 48 and not menopausal yet (Thank God) and my breasts have grown from a 34 A to now a 34 DD yep that’s right a DD. I don’t know what to do with them!! I thought the girl that was re sizing me at Victoria’s Secret was on crack when she told me. This is insane. Mind you I have great cleavage but really at my age?
I am blaming my husband as I don’t have any other excuse!
Gotta love zombie boobs!
With Halloween fast approaching, there is probably a costume for that.
Um, could it be Nature’s Way of telling you ya better reproduce, NOW?
So what exactly has your husband been doing to them?
As we age, it’s perfectly normal for breast tissue to get replaced by fatty tissue. Fatty tissue is less dense, so it takes up more room while weighing the same. This is also the reason our boobs start to sag as we age.
And I hope it makes mammograms easier.
They suck when you have “dense breast tissue”.
I wish the OP would return and let us know if she found any medical cause for this.
And I also wish all lame, juvenile comments in this thread would cease. Faint hope, that.
They had to repeat my last mammogram twice because I have such “dense breast tissue”. That was fun 
I was a B cup up until I hit my 50s. Now I’m a C. It took me awhile to figure out why I suddenly starting having cleavage…
I haven’t seen any lame, juvenile responses since the thread was zombified. Knee-jerk any? I also thought MsBatt posted a reasonable-sounding answer. I was going to post something similar but, being a guy, felt if such a post came from a woman, it would carry more weight.
I do. So what are you doing this weekend? 
Just to start off, I’m a male, so am probably talking through my hat.
Seems to me that breasts do increase in size with age. My wife went from a B to a C with no gain in weight. Also, in both men and women, adipose tissues shrink in the extremities while growing in the trunk. So legs and arms may be slender on a more rotund trunk (line myself). I don’t know the physiology of this phenomenon, but have consistently observed it to be true.
Other than that, ??? I personally think it is due to long term exposure to estrogen; other examples include continual growth in the prostate in men, and the appearance of hair in unusual places as men age.
This also happens in women post menopausal, as testosterone assumes a more dominant role in the female hormonal mix.
So hormones have long term effects that are not initially apparent.
Right.
What did you figure was the reason? Or am I missing something.