Why is my dog's nipple swollen and red during her first heat cycle?

That could be a normal reaction of the mammary glands after the season, and it is likely to resolve spontaneously one or two weeks after the season. if signs persist more than that and discharge comes out from nipples a check up would ideal as false pregnancy or mammary gland inflammation/infection may be present.

Hello. If you are sure that she is not pregnant, then this is just a hormonal response. The breast gland tissue may regress a bit, but as long as she remains unsprayed, she may develop a little more with each heat cycle. Spaying her now may help regress the tissues totally, but with each additional heat cycle, she may develop just a little bit more. So yes, this is a normal condition in an unsprayed female dog. Thanks for using Petco Pet Education Center, formerly Petcoach.

Hello. The nipple is definitely red & inflamed, but this does not always indicate the presence of an infection. For now, you can rub a little 1% hydrocortisone on the skin 2-3 times a day, & if it is not looking any better by early in the week, please have your veterinarian take a look. Thank you.

a higher hormone activity level such as during heat can indeed make the mammary complexes get more blood supply in preparation for a possible pregnancy. This should go away a little while after coming out of estrus (estrus = heat, and your dog is in heat for about three weeks after she stops bleeding. If the redness does not subside, or if the skin starts to look diseased, you should have your vet give Fufu a skin exam.

It is not unusual for the vulva to remain swollen for a period of time after the "heat" cycle is over. In dogs, there are [4 stages of estrus](https://www.petcoach.co/article/anatomy-and-function-of-the-reproductive-system-in-dogs). The combination of proestrus and estrus, which is often referred to as "heat" by breeders, lasts approximately 21 days. "Heat" is followed by diestrus and anestrus. During proestrus, the vulva swells and has a bloody discharge. During estrus, the vulva softens and becomes pliable in preparation for mating. It can take several weeks following estrus for the vulva to shrink back down in size, but it will never go back to the size it was before the first heat cycle. The same is true of the mammary glands, which enlarge slightly in preparation for [pregnancy](https://www.petcoach.co/dog/condition/pregnancy/).

Hello. This is nothing to be overly concerned about. Manakoa is old enough that there are hormones circulating & this nipple just seems to be a little more sensitive to the effects of estrogen at this point in time. If you were planning on spaying her, this is a good time to consider doing so, but otherwise, as long as the nipple does not continue to show further hormonal influence, it should not significantly affect her. If it does continue to enlarge & seems to bother her, do see your vet. Thanks for contacting Petco Pet Education Center, formerly Petcoach.

Hello and welcome to Petco Pet Education Center, formerly Petcoach. It is possible that Harley could be going through something called 'pseudo-pregnancy'. Dogs can develop mammary glands, produce milk, and will sometimes even start to nest and collect small stuffed animals to nurse. This is normal and will subside in a few weeks. However, it is recommended to get her spayed before her next heat so she doesn't have to go through that stress again. The other possible cause is something called a pyometra. This is an infected uterus and is life-threatening. If you notice any discharge from her vulva, if she is weak, not eating, drinking more, or acting abnormally at all, I would have her seen by your vet right away. Best of luck with Harley.