• Cramps but no period could be caused by normal ovulation pain or an ovarian cyst.
• If you suspect you may be pregnant, abdominal cramps could also be caused by an ectopic pregnancy, a miscarriage, or pregnancy itself.
• You may also feel abdominal cramping if you have chronic conditions like endometriosis or inflammatory bowel disease (IBD).

Many of us have felt the uncomfortable lower-belly cramps that can come with your period. But cramps can show up outside of your period, too.

There are many conditions that can trigger abdominal cramps - and while many are normal, some may be dangerous and could require medical attention.

Here are nine reasons you may have cramps while not on your period, and some tips for how to tell what is causing your cramps.

1. Ovulation

Ovulation cramps happen when one of your ovaries releases an egg as part of your monthly menstrual cycle. About one in five women experience cramps when they ovulate.

These cramps usually come about 14 days before your period and can feel like a sharp twinge of pain or a dull ache. Ovulation cramps are usually only on one side of your lower belly and can last from just a few minutes up to a couple of days.

2. Ovarian cyst

Ovarian cysts are small sacs filled with fluid that grow inside or along the outside of your ovaries. Ovarian cysts are relatively common, affecting about one in five women in the US, and small ones may not cause any symptoms. But larger ovarian cysts can cause intense cramps in your lower belly, usually just on the side where the cysts are growing.

If you have fever or vomiting along with your cramps, you should get medical attention. This is a sign that a cyst may have ruptured, which can cause internal bleeding.

3. Pregnancy

During your first trimester of pregnancy, you might have some cramping caused by your uterus expanding.

In your second trimester, you may also have cramps when the muscle that supports your uterus stretches. In most cases, these cramps are not severely painful and should only happen occasionally.

"Usually, cramping during the early part of pregnancy is very mild," says Christine Greves, MD, a gynecologist at the Winnie Palmer Hospital for Women and Babies.

4. Ectopic pregnancy

An ectopic pregnancy happens when a fertilized egg implants outside of your uterus, usually in your fallopian tubes. Ectopic pregnancies are a type of miscarriage, but unlike most miscarriages, you will need specialized medication or surgery to remove the pregnancy.

Ectopic pregnancies can cause intense, painful cramping along with other symptoms. "An ectopic pregnancy may involve heavy vaginal bleeding, severe abdominal pain, lightheadedness, and dizziness," Greves says.

5. Miscarriage

A miscarriage happens when you lose a pregnancy before it has reached 20 weeks. Up to one in five pregnancies end in miscarriage, and most of the time, you will have painful cramps. Miscarriage cramps may last for only a short time, but they can stretch for hours in some cases.

"A miscarriage generally can cause lower pelvic cramping that doesn't favor a side," Greves says. "There may be spotting or bleeding that accompanies it." Another sign of a miscarriage is if you are passing fluid and tissue from your vagina.

6. Pelvic inflammatory disease

Pelvic inflammatory disease (PID) happens when you have an infection in your reproductive organs, including your ovaries, uterus, or vagina. PID is often caused by sexually transmitted infections like gonorrhea or chlamydia.

PID can cause painful cramps, but there are often other symptoms as well, like fever, bad-smelling discharge, and a burning feeling when you pee.

7. Inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic condition that causes damage to your digestive system. IBD makes it harder for you to digest food and, in some cases, it can trigger dangerous bleeding in your intestines.

IBD can cause pain and cramping in your abdomen, especially after eating, but it may also come with symptoms like diarrhea and bloody stool. In many cases, IBD can make you lose your appetite as well, which can lead to weight loss.

8. Endometriosis

Endometriosis is a chronic disorder in which extra tissue grows on the outside of your uterus, ovaries, or other nearby organs. This extra tissue can cause extreme pain and cramping, especially during your period or during sex.

Other signs of endometriosis are abnormally heavy periods as well as bleeding in between your periods. You may also have pain while you pee or during bowel movements.

9. Appendicitis

Appendicitis is a serious condition in which your appendix suddenly becomes inflamed, often because of an infection. Appendicitis can be dangerous - if you don't get treatment quickly to have your appendix removed, it can rupture and cause a widespread infection or even death.

"Appendicitis usually involves right lower quadrant pain, lack of an appetite, and a fever," Greves says. Appendix pain may start out feeling like a normal stomach ache, but it doesn't go away and will keep getting worse until you get treatment.

Insider's takeaway

There are various reasons you may be having belly cramps and in many cases, there is nothing serious to worry about. But if you have pain that feels unusual or concerning, it's best to reach out to your doctor to make sure there aren't any serious medical issues.

Dweck says you should contact your doctor if you have any severe or unfamiliar pain, particularly if you are pregnant.

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