Several possiblites. I hope you washed right away afterwords.

Not washing before the appointment. Diet and sexual transmitted diseases such as HPV. Do some research and you see women who have HPV state they have a smelly pussy odor problem. Another one is bacterial vaginosis.

http://www.cdc.gov/std/bv/stdfact-bacterial-vaginosis.htm

http://www.cdc.gov/std/hpv/stdfact-hpv.htm

if a lady has a constant problem or medical issue she shouldn't be providing. Otherwise, checking herself is easy enough and if she doesnt, shame on her.

I've had two appointments when this was an issue.Both ladies  I had seen before and never had a problem. One of the ladies, obviously, forgot to use deodorant. The other was not so clear. she was fine at the beginning but after a break midway through she went to the bathroom. During the next round out came an odor that was previously non-existent and it wasn't coming  from behind either.

.....some things can't be washed away without being cared for in other ways. If it was smelling that bad still she might've had bv or something like that or worse (std).  

So....if you smell something tell her plainly. Because again if you smelled it she was already aware of it before taking your date. She shouldn't have been working like that.

-- Modified on 6/8/2014 5:43:54 PM

the likeliest, in my opinion, is a pH imbalance of some sort -- ie, bacterial vaginosis (possibly also a yeast infection, but BV or something called trichomoniasis, which is also a possibility and also easily treated with a round of antibiotics, are the likeliest culprits).  BV sounds a lot worse than it really is, and is not necessarily a STI; but it's still in your best interest to go through a round of antibiotics after sexual activity with someone you suspect has BV, because you could pass it on to others.

the other possibility is that... and this one is significantly grosser... that she accidentally left a feminine product (ie a tampon) in there and forgot about it, and now it's lodged pretty deeply inside her vaginal cavity. :-/

yes, there is, of course, a nice way to tell her.  that doesn't mean she'll like to hear it... but she needs to hear it.  while there is a range of feminine scent (i've been with women who have a very delicate, almost floral sort of scent; and women with a more pungent, earthy/musky scent), a fishy smell is not generally normal.  i would just gently advise her that she smelled a bit 'off.'  tell her that you enjoyed her time with her, but are sincerely concerned about her health.  that won't guarantee she'll be okay with the news, but... it's the more ethical thing, IMO, to tell her.  i would want to know.