The early signs and symptoms of pregnancy may be very unspecific, closely resembling premenstrual symptoms. For some women, it can be hard to tell the two situations apart. Early pregnancy signs can be so misleading that it is even possible that, in the first days of pregnancy, the woman presents a mild vaginal bleeding caused by the implantation of the egg in the uterus wall.
It is not uncommon, therefore, to find women who only discover they are pregnant after 3 or 4 months of gestation, simply because they have confused the early symptoms of pregnancy with their premenstrual symptoms, and the mild vaginal bleeding with an actual menstruation.
In this article, we will explain the differences between the signs of pregnancy and menstruation. In order to facilitate the reading of this text, we will write it in the form of FAQ.
Can you get your period while you’re pregnant?
No. You can’t have your period while you’re pregnant. A pregnant woman may even have vaginal bleeding during pregnancy, but technically she does not menstruate.
Why the vaginal bleeding of a pregnant woman will never be considered menstruation?
During the menstrual cycle, the cells of the endometrium (internal wall of the uterus) proliferate, making the uterus thicker and with highly vascularized layers. The endometrium proliferates to become a suitable place to receive a fertilized ovum and initiate a pregnancy.
If the woman ovulates and conception does not occur, the hormonal stimulus for the expansion and maintenance of this thick uterine wall disappears. As the estrogen and progesterone levels drop, the small arteries bringing blood supply to the endometrium close off. Without adequate blood supply, the endometrium becomes deprived of nourishment and oxygen, and eventually collapses.
Menstruation, therefore, is not exactly a blood loss, but rather the shed of uterine tissue along with blood vessels and coagulated blood.
During pregnancy, the internal wall of the uterus does not collapse, otherwise, the fetus would be carried along, causing a miscarriage. Therefore, any bleeding that occurs during pregnancy cannot be considered menstruation. Menstruation and pregnancy are incompatible events.
What are the causes of bleeding in early pregnancy that can be confused with menstruation?
Between 20 and 40% of pregnant women have at least one episode of vaginal bleeding during the first trimester of pregnancy. There are various causes, including implantation of the egg (fertilized ovum) in the uterus, hormonal variations, lesions or wounds in the vulva, vagina or uterus, miscarriage, threatened miscarriage, ectopic pregnancy, etc.
The main clue is a change in the usual characteristics and timing of your menstrual bleeding. If you are of childbearing age, have recently had sex without proper contraceptive protection (i.e. condoms, pills, or any other contraceptive method) and few days later have had a vaginal bleeding that is different from what you are used to seeing, this may be a sign of pregnancy.
Pregnancy bleeding is usually bright red, except in few situations, such as ectopic pregnancy and miscarriage, when bleeding is darker. In many cases, nonetheless, the general characteristics of the bleeding are often very different from those of menstruation.
So, is it easy to distinguish menstruation from vaginal bleeding during pregnancy?
Not always, especially if the woman does not yet know that she is pregnant.
The characteristics of menstrual bleeding are different from woman to woman. There are those who have a small, short-lived menstrual flow that may look like the type of bleeding that can occur during the early stage of pregnancy. It is, therefore, not uncommon to find women who bleed during the first few months of gestation and mistakenly think that their period is coming as usual.
Three issues should be taken into account when evaluating vaginal bleeding:
- Is the bleeding coming on the expected date of menstruation?
- Does the bleeding have the usual duration time and volume of your period?
- Are the characteristics of the blood similar to your period?
If you answered yes to at least 2 of the 3 questions, the chance of it being just menstruation is quite high.
What are the other pregnancy signs that are similar to those of menstruation?
Some premenstrual symptoms, such as cramps, fluid retention, breast enlargement, mood swings, and many others, may occur both in early pregnancy and during the premenstrual period. The clue again is the same used to distinguish bleedings: compare the characteristics of the symptoms.
Usually, the symptoms of pregnancy may be similar, but not exactly the same as in the period right before the menses.
The feminine intuition is something that must always be taken into account. When a woman feels that there is something different about her menstrual pattern or premenstrual symptoms, it is always a good idea to take a pregnancy test to rule out an early pregnancy, especially if the period is late.
Obviously, if the woman has not had intercourse in the past 4 months, there is no way she is in the early stages of pregnancy. In this case, changes in the menstrual pattern should be evaluated by a gynecologist.
Does having a late period always mean pregnancy?
Of course not. If, on the one hand, every pregnancy causes menstrual delay, the opposite is not true. Not every menstrual delay is synonymous with ongoing gestation. There are several causes for a late period, including emotional stress, infections and interruption of a contraceptive pill (see: WHY IS MY PERIOD LATE? 15 Possible Reasons).
Therefore, if your menstruation has been delayed for some days, there may be better explanations other than pregnancy. However, every sexually active woman with a menstrual delay greater than one week should take a pregnancy test to rule out pregnancy.
Trying to guess if you are pregnant or not only based on the symptoms isn’t very efficient. The diagnosis of pregnancy should be done with exams and not with a “crystal ball”.
The most correct thing to do is the following: If your menstruation is late, and you suspect that you may be pregnant (even if the suspicion is very slight), take the pregnancy test. With at least one day of menstrual delay, the vast majority of tests have a high sensitivity rate, close to 100%.