Nipple discharge 

  • Overview


One of the most obvious explanations for fluid leaking from the nipple is that you're pregnant or currently breastfeeding.

Nipple discharge may also be caused by a wide range of conditions, most of which are harmless or easily treated.

If you are unsure of the cause of your breast discharge or you're embarrassed or worried, see your GP, especially if the discharge is bloodstained or only comes from one breast.

Am I pregnant?

If the discharge is milky and comes from both nipples, the most likely explanation is that you're pregnant.

In pregnancy, the breasts may start to produce milk from as early as the second trimester (weeks 14-26), and some women continue to produce milk up to two years after stopping breastfeeding.

If you think you may be pregnant, see your GP or pharmacist for a pregnancy test. You can also read our article on Am I pregnant?

Non-pregnancy causes

If pregnancy has been ruled out, it's likely that your nipple discharge is caused by one of the following conditions:

  • duct papilloma – this is a harmless growth inside your breast duct (the tube that carries milk from the gland to the nipple) that typically causes bloodstained discharge from one breast
  • duct ectasia – this is a harmless, age-related breast change that can result in a cheesy or discoloured discharge from both breasts 
  • breast or nipple abscess – this is a painful collection of pus that forms in the breast tissue or around the nipple, usually as a result of bacterial infection

These conditions are explained in more detail below to give you a better idea of whether you may be affected. However, it's important to see your GP for a professional diagnosis and treatment.

Duct papilloma

If the discharge is bloodstained and from a single breast, the cause is likely to be duct papilloma.

A papilloma is a harmless wart-like growth, usually about 1-2cm in size, found inside one of the breast ducts. The breast ducts carry milk from the gland to the nipple (see diagram). The papilloma is usually just behind the nipple and can cause fluid or blood to seep out of the nipple. 

You'll usually just have one papilloma, which means it can be easily removed.

Although the discharge may be alarming, rest assured that papilloma is not cancer and is not likely to turn into cancer. However, you should still get it checked by your GP so they can rule out breast cancer and offer you any necessary treatment.

Duct ectasia

If the discharge is brown, green or cheesy, it's likely you have a harmless condition called duct ectasia.

Duct ectasia tends to affect women approaching the menopause. As the breasts age, the milk ducts behind the nipple get shorter and wider and may produce a discharge. This is a normal, age-related change and nothing to worry about.

A lump can sometimes be felt behind the nipple, which is just scar tissue, and the nipple sometimes becomes inverted.

Even though this condition is harmless and tends to clear up without treatment, it's important that you see your GP so they can rule out breast cancer. Having duct ectasia does not increase your risk of developing breast cancer in the future.

An abscess

If the discharge contains pus, the cause will probably be a breast abscess or abscess around the nipple.

An abscess is a painful collection of pus that usually forms under the skin after a bacterial infection. The surrounding skin may also be red, warm and swollen.

A breast abscess is usually a complication of mastitis (inflammation of the breast). If you have been to see your GP because of mastitis, you may already have been given antibiotics. If after taking antibiotics your breast is still hard, red and painful, your GP may refer you to a specialist breast unit to confirm the diagnosis of a breast abscess.

More unusual causes

Less common causes of nipple discharge are:

  • the contraceptive pill – the discharge is usually just a temporary side effect of starting the pill (some women also get breast tenderness and breast enlargement)
  • fluctuating hormones from puberty or the menopause
  • previous breastfeeding – some women continue to produce milk up to two years after they've stopped breastfeeding  
  • stimulation of the nipples, for example through sex
  • medication that causes raised levels of the milk-producing hormone prolactin – this includes SSRI antidepressants and tranquillisers
  • a type of non-cancerous brain tumour called a prolactinoma, which causes raised levels of prolactin
  • a hormone problem such as an underactive thyroid gland or Cushing's disease
  • a clogged milk duct called a galactocele, which is usually associated with childbirth 
  • an early form of breast cancer called carcinoma in situ, which is found inside the milk ducts and hasn't yet spread (it is usually picked up during a routine mammogram)

When you should be referred

Your GP should refer you to a specialist for further investigation if:

  • you're over 50 (unless there's an obvious harmless reason for your discharge)
  • you have a bloody discharge
  • you are a man with nipple discharge

Breast cancer is an unlikely cause, but needs to be ruled out, especially if:

  • you are over 40
  • you have a breast lump
  • your discharge contains blood
  • only one breast is affected

Page last reviewed: 17/05/2013

Next review due: 17/05/2015


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The 4 comments posted are personal views. Any information they give has not been checked and may not be accurate.

Temil said on 01 October 2014

I'm 18 years old, and recently I've noticed milky discharge coming out of my left nipple. I'm currently on my period and its still happening. Its really strange because I'm a virgin...

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Xti19 said on 21 April 2014

I'm 21 years old, I have been having green and occasionally milky discharge from my left nipple for the last year and a half, I though I'd share my experience on here for any other lady who's as worried as I was. I noticed the discharge by chance, it only appeared when I applied pressure. Seeing as I had no lumps I left it go a month to see if it would clear off on its own. When it didn't I went to see my GP who examined me and took blood tests (which came back normal) before deciding she didn't know what was wrong and referring me to the hospital for scans ect. At that point I got even more worried, fearing the worst. I was then informed that I had been put onto 8 week waiting list for the tests.
seeing as I have a dreadful history of breast cancer in my family including my grandmother, an aunt who discovered her cancer at 25 and a great aunt who died at 36 with breast cancer, I decided to go private.
I went immediately to the specialist for tests where he examined me and told me that it was completely normal, that my breast tissues were just making allot of fluid that wasn't being broken down, but that's just my breast. On my insistence he scanned me to be sure but found no irregularities at all.
The fluid stopped appearing last month.
I hopefully this post will give a little reassurance to anyone experiencing the same problem and worrying, all the same I would highly recommend going and getting checked out, Especially if you have bloody discharge. Hope this helps ladies!

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suzza42 said on 19 October 2011

I am also 21 years old and got all the symptoms how ever i am currently waiting an appointment for my second round of blood tests and has been dreading what they may find. . . i have been told that it was nothing and then i got told it may be worse than they predicted . . . i am now thinking all sorts of what it could be but i am just thankful that someone else has gone through what i am going through now. This problem is effecting my day to day life and family members say i am not myself all because the doctors find the symptoms interesting but don't know why it is happening. . . . i hope i will get an answer soon . . .

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kin21 said on 14 October 2011

I'm 21 years old and have suffered from milky nipple discharge for over a year now. All of the possibilities listed on here, I have been tested for, yet there has been no conclusion so far. I have been worried sick taking multiple pregnancy tests, having x-rays and scans and having repeat blood tests to determine the reason to why my body is behaving this way. After all of that drama, the doctor said it must be normal for me and that my body is "just being hypersensitive" to my hormones. I was shocked with the response but I feel there's nothing else that I can do.

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Am I pregnant?

What to do if you think you might be pregnant, including pregnancy symptoms, tests and what to do next