A couple of weeks ago I read an article about a woman in Utah named Angie Hernandez who only realized that she was pregnant upon giving birth to her daughter. She had recently been feeling unwell but otherwise she claims to have had no pregnancy symptoms. The article even notes that, “She said she even had regular menstrual cycles and wore her regular pants.”
Wait, is that even possible? The regular menstrual cycles thing not the regular pants thing — I personally found that many of my pre-pregnancy pants were still comfortable during my pregnancy.
The “missed period” is a pregnancy symptom staple. Before there were home pregnancy tests, blood tests, or ultrasounds, there was the “is my period late?” test. And it’s worked pretty well for most women throughout history. And yet Hernandez’s story isn’t unique. How many times a year is there a news story about a woman who didn’t know she was pregnant until she gave birth in her toilet? Or maybe you know someone who had not only a surprise pregnancy but a surprise birth. And many of us have probably heard a story about a friend, a cousin, or a friend’s cousin’s sister and how she had regular periods throughout her pregnancy.
So what’s the truth — can you have your period while pregnant?
Technically speaking no, you can’t experience menstruation when you’re pregnant. This is because menstrual bleeding is the shedding of the uterine lining, and the uterine lining does not shed during pregnancy. As Our Bodies, Ourselves explains, “If a fertilized egg implants into the uterus, it sends a signal to the ovary to keep making progesterone, which will help sustain a pregnancy by keeping the uterine lining thick and nourishing.”
In a typical menstrual cycle, the shedding of the uterine lining is followed by the follicular phase in which an ovary prepares to release an egg. During pregnancy the ovaries stop releasing eggs, therefore the follicular phase, ovulation, and the luteal phase do not occur. Basically the entire menstrual cycle goes on hiatus during pregnancy, as well as for a period of time postpartum. The length of this postpartum amenorrhea period varies depending upon a woman’s individual body and whether or not she is breastfeeding.
So if Angie Hernandez was not technically having menstrual periods, what was she experiencing? What are the reasons why a pregnant woman would think she is having her period?
Although a pregnant woman does not experience menstrual bleeding, she may still experience vaginal bleeding. According to Planned Parenthood, vaginal bleeding happens in 20% of pregnancies. This bleeding is usually only a small amount and most often occurs only in the first trimester, although for some women it continues into the second or even third trimesters. A common cause of bleeding during early pregnancy is implantation bleeding. Implantation occurs when the fertilized egg attaches to the uterine wall, generally about two weeks after conception (so right when you’d probably be expecting your period!). A similar form of light bleeding that some women experience during pregnancy is known as breakthrough bleeding. Breakthrough bleeding is thought to be caused by the hormonal shifts that happen in pregnancy. It usually occurs in the first trimester (again when you’re likely to be expecting your period), and lasts for a few days, although for some women it continues into the second trimester.
Implantation bleeding and breakthrough bleeding are more like spotting than an actual period and are not reason for concern. However, heavy vaginal bleeding during pregnancy warrants a call to your care provider, as this may be a sign of a problem that requires medical attention. Ectopic pregnancies, in which the fertilized egg implants somewhere other than the uterus (usually the fallopian tube), can present with vaginal bleeding along with abdominal cramping. Although only about 1 out of every 60 women experience an ectopic pregnancy, it can become dangerous if not addressed quickly. Infection, inflammation, or growths in the pelvic area can also cause vaginal bleeding during pregnancy. Your care provider can help determine the precise problem and how to best address it so that you can continue to have a healthy pregnancy.
A frightening cause of vaginal bleeding during pregnancy is miscarriage. This is a common fear among pregnant women if they experience any vaginal bleeding, but vaginal bleeding by itself is not necessarily a sign of a miscarriage. As the website Better Pregnancies notes, “Only when the bleeding is coupled with severe cramping in the lower stomach and when you notice tissue being released from the vagina should you be worried.”
When significant vaginal bleeding occurs in late pregnancy (after 20 weeks or so), it could indicate a problem with the placenta, which is the organ that supplies nutrients and oxygen to the growing baby and gets rid of waste products in the baby’s blood. Bright red bleeding that isn’t accompanied by abdominal pain may be a sign of placenta previa. This is when the placenta partially or completely covers the cervix, which nearly always necessitates a cesarean birth to ensure the safety of the mother and baby.
Vaginal bleeding that is dark red and accompanied by pain may be a symptom of placental abruption. In this case the placenta begins to separate from the uterine wall during pregnancy. The amount of bleeding varies depending upon how large a section of the placenta has detached. A woman may still be able to give birth vaginally with a placental abruption, but if the condition begins to affect the baby a cesarean birth may be necessary. These conditions affecting the placenta are serious and certainly sound scary, but fortunately they are also rare — placenta previa happens in about 1 in every 200 live births, and placental abruption happens in about 1 in every 100 live births.
So there you have it. I’ve given some reasons why light bleeding may occur during pregnancy (which usually aren’t reason to worry) and some reasons why heavy bleeding may occur during pregnancy (which warrant a call to your care provider). None of these causes however, is menstrual bleeding.
Depending on the usual amount a woman bleeds during her period, the usual length of her period, and the usual length of her cycles, it does however make sense how one of the causes of vaginal bleeding discussed above might be mistaken for continuing to have regular menstrual bleeding throughout pregnancy. I, of course, don’t know the reason why Angie Hernandez continued to experience regular vaginal bleeding throughout her pregnancy, but I am happy that by all reports her pregnancy ended with a healthy birth, baby, and mother. Every female body and every pregnancy is different, and modern medical science still knows relatively little about how the female body works. I believe there is definitely room left for some mystery when it comes to how different women experience pregnancy.
Brigid Taylor is a women’s health and rights advocate, a Lamaze Certified Childbirth Educator, and an avid-reader. Read her full bio here.