You can't have your period when you're pregnant, but you may still bleed

• It isn't possible to be pregnant and have a period, but you could still have vaginal bleeding or spotting throughout your pregnancy.
• Bleeding during pregnancy can be common, however, significant bleeding could be a sign of more serious complications like an ectopic pregnancy or a miscarriage.
• If you're experiencing bright red bleeding, make sure to contact your doctor immediately.

No, it's not possible to have your period while pregnant. However, you still may experience light bleeding or other period-like symptoms like bloating, fatigue, and spotting.

"Bleeding during early pregnancy can be quite common - in fact, it occurs in 15 to 25% of pregnancies in the first trimester (less than 13 weeks)," says Lauren Demosthenes, MD, senior medical director of Babyscripts. "In addition to bleeding that may be mistaken for a period, some women may experience pelvic heaviness or mild cramping that may feel similar to a period. "

Vaginal bleeding during pregnancy can be common and doesn't necessarily mean that there's something wrong. However, bleeding can be a warning sign of something serious such as a miscarriage or ectopic pregnancy.

In this article, we'll discuss why you may be experiencing vaginal bleeding during pregnancy and what it could indicate.

Why can't you technically have a period when you're pregnant?

Throughout the month, your body prepares for pregnancy. It does this by building up the endometrium, or uterine lining. If you become pregnant, this lining serves to help nourish the fertilized egg at the very early stages of pregnancy. If you don't become pregnant, your body sheds the endometrium, via your period. Therefore, it's impossible to be pregnant and have a period, because you don't shed your endometrium while pregnant.

What could period-like symptoms during your pregnancy mean?

"Period symptoms and early pregnancy symptoms are very similar and can be very confusing and difficult to distinguish," says Dori Gelfman, a registered nurse at Fruitful Fertility. "Stomach cramps, sore or tender breasts, and backaches can occur in both instances."

Though the symptoms of pregnancy can vary, these symptoms can sometimes mirror those of PMS.

Signs and symptoms of both PMS and early pregnancy can include:

• Vaginal bleeding or spotting
• Back pain
• Headaches
• Cramping
• Moodiness (anxiety, irritability, crying, etc.)
• Breast pain or swelling
• Increased urination

"It's also common to have some mild cramping - without bleeding - throughout the pregnancy," says Demosthenes. "If this occurs it may just indicate that your ligaments are stretching or your pubic bone is softening which is totally normal. Some women turn to maternity support belts for this - or a period of laying down to relieve some pressure."

What are the causes of vaginal bleeding during pregnancy?

According to a study published in the Annals of Epidemiology, 25% of pregnant women may experience spotting during their first 12 weeks of pregnancy.

There are a variety of causes for vaginal bleeding during pregnancy. The causes of vaginal bleeding are often dependent on the trimester you're in. The below table categorizes what bleeding may mean during different trimesters.

"In the first trimester, bleeding can occur about one-to-two weeks after fertilization when the pregnancy implants into the uterus," says Demosthenes. "The cervix also has some changes in pregnancy which may lead to some slight bleeding after intercourse, a pap smear, or pelvic exam. All of this bleeding is scary but harmless."

Although light vaginal bleeding may not be cause for concern in the first trimester, spotting or bleeding during your second trimester may be a sign of a medical emergency.

"During the second half of pregnancy, bleeding can mean something serious so should always be checked out," says Demosthenes. "Bleeding, pelvic pressure and a mucous discharge can signal something called an 'incompetent cervix' - this is more common in the second trimester."

If you're experiencing vaginal bleeding of any kind while pregnant, you should seek immediate medical attention as it could indicate something more serious such as an impending miscarriage or ectopic pregnancy.

"Always call your doctor if you experience bright red bleeding - either continuous bleeding or a sudden gush of blood," says Gelfman. If you are bleeding and find that the blood is excessive (i.e. completely soaking a panty-liner or underwear in blood) or if you have an intense, stabbing pain on one side of your body, seek immediate medical attention, says Gelfman. These can be signs of something more serious and warrant attention immediately."

Insider's takeaway

Although vaginal bleeding in early pregnancy, or even throughout a pregnancy, can be alarming, it's fairly common and not always a sign of a serious condition.

"You should always ask your doctor if you are questioning what is going on with you or if something doesn't feel right," says Gelfman. "Trust your instincts. It's better to call and be told it is nothing rather than worrying about what it could be."

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