My senior mare has a large swelling on top of her buttock .we first noticed it mid january and then concluded it might be a bruise from a slip and fall she had on the ice a few days earlier.About a week later i noticed small amounts of blood coming out her vagina on and off ,basically right next to that swelling.at first we didn’t think there would be a connection and when running it by the vet,assumed she might have a vaginal varicose vein or a small injury near the vaginal exit.the bleeding was minor and only on and off ,some days nothing at all and we thought whatever it was had healed but then it started up again.meanwhile the swelling had grown a little bit ,was now the size of medium cantaloupe.so the vet came ,had a look and recommended to drain the swelling in the hope of stopping the vaginal bleeding.the thought was that the fluid of the swelling was seeping into the vaginal area .and indeed ,it solved that problem ! he also checked the urinary tract and the vaginal vault ,saw nothing suspicious or unusual but prescribed antibiotics "just to be sure ".an incision was made at the lowest point of the swelling and it drained quite a bit.mostly blood and serous fluids.was told to flush the incision for a good 5 days which i did.everything looked much better until the area started to fill up again.since the incision was still open,it drained some more ,mainly after she got up from her naps -please note she is 34 and has a harder time to get up,more often that not sitting on her butt for a while - so this went on for quite a while,spontaneous draining followed by slow refilling.in april when nothing had changed ,i had the vet come out again .he said that it very likely JUST is a hematoma /seratoma ,probably not an abscess ( no pus and apparently not painful ) and that the only thing one could do would be to make a larger incision ,check the inside and possibly take out some growth,scar tissue etc ( if i remember his words correctly ) .not an option though considering the way she gets up .by now ,four months later,the swelling is still of the same size,some days a bit smaller ,other days larger .it sometimes still drains a little bit and it is still blood that’s coming out,not pus.of course it does bother the mare and i wish it would get absorbed by the body but might have to face that it never will.apparently there is no course of action but wait and hope for the best.i realize these things can take a LONG time but how long is long ? i also realize this could be a tumor or some sort of growth but surgery is not an option,partly due to her age ,partly due to the very long distance to the next animal hospital since we live way off the beaten track.
i’ve been reading all the previous posts about this topic and it looks like it is either DRAIN or DON’T DRAIN …currently thinking to wait it out but happy to hear any suggestions 
