Blood can change color during menstruation, ranging from bright red to pink to brown.

If you drop trou on your period and see anything but red, try not to panic. Period blood isn’t always red, and different colors of blood can mean lots of things.

Different blood colors aren’t usually a cause for concern. But occasionally, they may be a sign of something that warrants a visit with a healthcare professional.

Brown discharge is usually old blood that’s had time to oxidize, which is why the different hue. It can be associated with a few things:

The beginning or end of your period

The blood flow is slower at the start and end of your period, meaning it takes longer to exit your body.

The longer it sits in your body, the more time it has to oxidize, causing it to turn brown. In some cases, brown blood could be left over from your previous period.

Pregnancy

Brown blood or spotting can be a sign of implantation bleeding, which is an early sign of pregnancy. It usually occurs around 10 to 14 days after conception.

Some other signs and symptoms of implantation are:

  • mild cramps
  • swollen breasts
  • nausea
  • vomiting

Lochia

Lochia is postpartum bleeding that occurs for the first four to six weeks after giving birth.

This bleeding usually starts out heavy and turns pinkish or brown around day four.

Missed miscarriage

Miscarriage is usually associated with bright red bleeding, but some people experience what’s called a missed miscarriage, or sometimes a “missed abortion” or “silent miscarriage.”

With a missed miscarriage, the pregnancy stops developing, but the tissue doesn’t pass out of the uterus for at least 4 weeks. There isn’t heavy bleeding, only dark brown spotting or bleeding.

Any bleeding during pregnancy warrants a visit to your healthcare professional.

Perimenopause

Fluctuations in estrogen levels during perimenopause affect the lining of your uterus.

This can cause changes to your flow’s frequency, texture, and color, including brown period blood or spotting at different times during your cycle.

The brown blood is usually just blood and uterine tissue making its way out of you.

Perimenopause symptoms can range from mild to severe. Along with changes in your period, you can also experience hot flashes, vaginal dryness, and sleep problems.

FYI, the average age to go through menopause is 51, but perimenopause can start as early as your 30s.

Polycystic ovarian syndrome (PCOS)

PCOS can prevent ovulation. When this happens, your uterine lining builds up but doesn’t shed properly, leading to light or missed periods with brown blood or discharge in between.

Here are some other PCOS symptoms to be aware of and bring up with a healthcare professional:

  • excess hair growth
  • weight gain
  • trouble getting pregnant
  • acne

You might notice dark red period blood when you first get up in the morning or after lying down for a while.

The deep red shade may be due to gravity, which keeps the blood in the uterus for a while but not long enough for it to oxidize and turn brown.

Dark red blood is also associated with:

The end of your period

Dark red blood near the end of your period can result from your slowing flow.

Lochia

Postpartum bleeding is often dark red and heavy for the first three days. After that, the blood gets darker as the bleeding slows.

Fresh blood flowing fast — like at the start of your period — is bright red. For some, a bright red bleed may happen from start to finish, while for others, it may darken as the flow slows.

Bright red blood is also associated with:

Infection

Some sexually transmitted infections (STIs), like chlamydia and gonorrhea, can cause bleeding between periods.

STIs can also cause:

  • foul-smelling discharge
  • pain during penetrative sex
  • pain or burning when you pee

If you suspect you have an STI, consult with a healthcare professional for testing.

Other infections, like bacterial vaginosis or yeast infections, can also cause bleeding due to vaginal irritation.

Miscarriage

Bleeding or spotting during pregnancy doesn’t always mean a miscarriage, but it can. Consult a healthcare professional for any bleeding during pregnancy to be sure.

A miscarriage can cause bright red bleeding or clots. During a miscarriage, some people also experience abdominal pain, cramping, and dizziness.

Uterine polyps or fibroids

These noncancerous growths in the uterus may cause heavy flow during your periods or at other times throughout the menstrual cycle.

They can be large or small and cause other symptoms like pelvic pain and pressure.

Adenomyosis

Adenomyosis occurs when the tissue that normally lines your uterus grows into your muscle tissue, thickening it.

This can cause heavy, painful periods, ongoing pelvic pain, and pain during penetrative sex.

Pink blood at the beginning or end of your period, especially if you’re spotting, is usually just blood diluted by cervical fluid.

Pink blood is also associated with:

Lochia

From day four onward, lochia — or postpartum bleeding — may be pinkish or brownish in color.

Low estrogen

Sometimes, pink menstrual blood is a sign of low estrogen levels. Estrogen helps to stabilize the uterine lining.

Without it, you may shed the lining at times other times in your cycle, leading to the spotting of various hues, including pink.

Perimenopause, menopause, and using estrogen-free hormonal birth control, like the minipill or a hormonal IUD, can cause low estrogen.

Ovulation

Some people experience spotting during ovulation, which usually happens around mid-cycle.

Ovulation can also cause an increase in cervical fluid, which can dilute blood and make it light red or pink.

Miscarriage

If you’re pregnant, a gush of clear or pink fluid from the vagina may be a sign of miscarriage.

Other signs of miscarriage include:

  • cramping
  • passage of tissue
  • loss of pregnancy symptoms

Orange discharge can happen when blood mixes with cervical fluid. Orange blood is also associated with:

Implantation spotting

Some people report seeing orange or pink spotting around the time of suspected implantation or 10 to 14 days after conception.

Not everyone experiences implantation spotting, but it can range in color. If you have spotting that doesn’t turn into a period, it’s a good idea to take a pregnancy test.

Infection

Any abnormally colored or unusual discharge may also be a sign of bacterial infection or STI.

Some other STI symptoms that can accompany out-of-the-ordinary discharge color include a foul smell and pain when you pee or during penetrative sex.

Your period blood shouldn’t be gray or a similar hue, like off-white. If it is, consult with a healthcare professional.

Here’s why:

Infection

This hue may indicate that you have an infection brewing, like bacterial vaginosis. Other signs of infection include:

Miscarriage

If you’re pregnant, gray discharge may be a sign of miscarriage. Tissue passing from the vagina may be gray in color as well.

Seeing black period blood can be alarming, but like brown blood, it’s usually just old blood that’s lingered in your body too long. This is most likely to happen during low-flow days at the start or end of your period.

Here are some other possible (but less likely) causes of black blood:

Stuck or forgotten object

Black discharge may be a sign that a foreign object is stuck in your vagina (it happens). Maybe you accidentally forget to remove a tampon or insert a second one.

Sex toys, menstrual cups, and contraceptives, like diaphragms, caps, and condoms, are other objects that can get stuck in your vagina.

Over time, these can irritate the lining of your vagina and cause an infection.

Along with black discharge, you might also notice a foul smell, itching or rash in your vagina and on your vulva, and a fever.

Consult a healthcare professional immediately if you suspect you have something stuck inside.

Infection

Pelvic inflammatory disease and STIs can cause vaginal bleeding and unusual discharge.

Heavy vaginal discharge of any color that has a foul smell can be a symptom of these, along with:

  • bleeding during or after sex
  • painful urination
  • itching
  • pelvic pain or pressure
  • spotting between periods

Missed miscarriage

Black bleeding or spotting can be a sign of a missed miscarriage that happens when the pregnancy stops developing but doesn’t pass out of your body for 4 weeks or more.

Other than dark brown or black spotting or bleeding, you may not have any other symptoms.

Lochia

Lochia, the postpartum bleeding that occurs four to six weeks after delivery, may start out heavy and red with clots, then slow and change to brown after the fourth day.

The flow could turn dark brown or black if it is especially slow.

Is it natural for the color to be different at the beginning and end of your period?

Yes! Your period may change colors from the beginning to the middle to the end. You may even have different colors from month to month or at different times.

In most cases, the variation from bright red to dark red to brown has something to do with the flow and time the blood has been in the uterus.

Your flow may be faster at the beginning of your period and trail off toward the end. You may also have dark red blood after lying down for a long time. You may see bright red blood on your heaviest days.

What if your period blood is watery or filled with clots?

Watery period blood is likely just new blood flowing quickly from your uterus. As for clots, these also typically aren’t a cause for concern. They happen as your uterus sheds its lining. Size matters, though.

If you pass clots bigger than a quarter in size, it’s worth mentioning it to a healthcare professional. The same goes for clots that accompany unusually heavy bleeding.

Heavy bleeding, or menorrhagia — which may or may not be accompanied by clots — can lead to anemia and cause symptoms like fatigue and shortness of breath.

A healthy period can be a variety of shades and textures, but some period changes should be mentioned to a healthcare professional.

For instance, if your period lasts longer than 7 days or is so heavy that you’re soaking through a pad or tampon every hour or two, it’s time to make an appointment.

Other reasons to make an appointment:

  • your cycles are irregular, changing dramatically in length from one month to the next
  • your cycles are shorter than 24 or longer than 38 days in length
  • you haven’t had a period in three months or longer
  • your bleeding is accompanied by other symptoms, like severe pain
  • you bleed between periods
  • you’ve gone through menopause and start bleeding again
  • you’re pregnant and start spotting or bleeding
  • you have gray discharge, which could mean a miscarriage or infection

Your period blood color and texture can change from cycle to cycle or even day to day, especially during certain stages of life, like when you’ve just started menstruating or are headed to menopause.

Most changes in period color aren’t a big deal, but it’s worth noting it and any other symptoms. Don’t hesitate to talk with a healthcare professional if you have any concerns about your period.