3 days VS 7 days for menstruation, which is normal?

"Menstruation" is a topic that makes many female friends anxious on a daily basis. Whether it will come, how much, how many days, whether it comes early or late... all seem to be problems.

But are these anxieties really a sign of illness, or are they unnecessary self-troubles? What are the menstrual conditions that really need to be taken seriously? Let’s talk about this today~

What is menstruation?

What is normal menstruation like?

On a certain social platform, a very widely discussed question is - "Is it abnormal to have a menstrual period of 3 days? Is it a sign of premature aging?"

Image source: Screenshot from a social platform

In fact, whether your menstruation lasts 3 days or 7 days, it is normal.

Let’s start with what menstruation is.

Just like the skin has epidermis and dermis, our endometrium also has basal layer and functional layer. Every month, the basal layer is affected by estrogen and progesterone to grow into the functional layer of endometrium rich in glands and small blood vessels.

If a fertilized egg is formed, the embryo can implant in the functional layer of the endometrium and obtain rich nutritional support and blood supply. If the embryo does not implant, the functional layer will shrink and peel off, and be expelled from the body with bleeding during the shedding. In the next menstrual cycle, the basal layer will grow a new functional layer.

When the endometrium is shed, a mixture of blood, tissue fluid and endometrium is excreted from the body, forming menstruation. Therefore, you can also understand that each menstruation is a process of "molting" of the endometrium. Since the functional layer of each menstruation grows newly in this menstrual cycle, it cannot be guaranteed that it will grow exactly the same every time, so it is common for the same person's menstruation to have slight changes.

Image source: NemoursKidsHealth

Menstrual cycle, menstrual time, and menstrual volume are all characteristic parameters of menstruation, and are important dimensions used to evaluate whether menstruation is normal.

In clinic, many patients are not clear about the method of recording menstruation, which leads to many misunderstandings when communicating with doctors. We can reach a consensus on the recording method first to avoid misunderstandings when describing menstrual characteristics.

Menstrual cycle and menstrual period time

We generally regard the first day of the next menstruation as the first day of a menstrual cycle. The time from the first day of menstruation to the complete end of menstruation is the menstrual time, and the interval between the first days of two menstruations is the menstrual cycle.

For example, if you have your period on the 11th of this month and it ends on the 16th, then your period is 5 days long and the 11th is the first day of your period. If you have your period on the 11th of every month, then the interval between the first days of your periods is about 30 days, and your period is considered to be about 30 days long.

The normal menstrual cycle is 28±7 days, which means that a menstrual cycle of 21 to 35 days is considered normal.

Domestic textbooks give a normal menstrual period of 2 to 8 days, with an average of 4 to 6 days. However, there is also a view that a normal menstrual period of ≤ 8 days is fine, because a short menstrual period does not necessarily mean that there is a specific disease. Therefore, within this range, 3 days and 7 days are both normal, and there is no obvious difference between good and bad.

Menstrual volume

Normal menstrual volume is defined as monthly blood loss of ≤80ml. It should be noted that the amount of bleeding is not equal to the amount of menstrual volume. Since menstruation contains not only blood but also tissue fluid and endometrium, the amount of menstruation must be greater than the amount of bleeding.

Menstrual flow is a very subjective judgment. Most people do not deliberately collect used sanitary napkins or tampons to strictly calculate the amount of bleeding based on the hemoglobin contained in them. Therefore, as long as the amount of bleeding does not affect physical health (such as excessive bleeding leading to anemia) and does not cause damage to psychological and social functions, it is assumed that the amount of menstrual flow is normal.

Of course, if you are curious about your menstrual volume, you can also refer to the following picture:

Image source: Wyatt KM, Dimmock PW, Walker TJ, et al. Determination of total menstrual blood loss. Fertil Steril. 2001; 76(1): 125-131(27)

Excessive menstrual flow vs. insufficient menstrual flow

What to look out for

Heavy menstruation

That is, the amount of menstrual bleeding is >80ml.

There may be many reasons for excessive menstrual bleeding. Some are obesity or excessive estrogen stimulation in certain diseases that lead to a thick endometrium. Some are uterine fibroids, adenomyosis and other diseases that cause the uterus to be too large or contract abnormally. Inflammation, tumors, endometrial polyps, coagulation dysfunction and other problems can also lead to excessive menstrual bleeding.

Regardless of the underlying reason, menorrhagia itself can lead to excessive blood loss, which can lead to the development of anemia. If a single menstrual period causes a large amount of acute bleeding, it may even be life-threatening. Therefore, for menorrhagia, it is necessary not only to stop bleeding for those with acute bleeding, but also to supplement iron or blood transfusion for those who are already anemic to correct anemia. It is also necessary to find the source of menorrhagia and intervene to prevent the condition from recurring or even worsening.

Lack of menstruation

That is, the amount of menstrual bleeding is less than 5ml.

Oligomenorrhea can be caused by many factors. The reproductive system is not fully developed during adolescence and ovarian dysfunction during perimenopause can cause physiological oligomenorrhea. If you are using hormonal contraceptives, such as oral contraceptives, implants, and intrauterine devices containing progesterone, the antagonism of progesterone on estrogen will cause the endometrium to be thin and the menstrual volume to decrease. Other conditions such as being too thin, exercising too much, anorexia, thyroid disease, and damage to the basal layer of the endometrium may also cause oligomenorrhea.

The International Federation of Gynecology and Obstetrics (FIGO) believes that most cases of "oligomenorrhea" do not involve pathological changes and do not require special intervention. Therefore, most people with "oligomenorrhea" do not need to be too anxious. If there is a disease that needs to be treated behind the oligomenorrhea, or if the oligomenorrhea affects the pregnancy plan of the pregnant woman, then see a doctor for targeted treatment. Otherwise, there is no need to worry about it.

When do you need to see a doctor?

Menstrual symptoms vary. What are the abnormalities that require medical attention? Here are some common menstrual problems that require medical attention:

1. The amount of menstruation suddenly increases or decreases significantly;

2. Dysmenorrhea suddenly becomes more severe than before;

3. Menstrual bleeding lasts for more than 8 days;

4. Menstrual cycle is less than 21 days or more than 35 days;

5. Bleeding between two menstrual periods;

6. Having sexual intercourse and delayed menstruation, suspected pregnancy;

7. No sexual intercourse but more than three months have passed since the first day of the last menstrual period;

8. Over 16 years old and still have not had menstruation;

9. Other situations that cause you worry or concern.

I wish everyone has an obedient, sensible and non-annoying menstruation.

References

[1] Xie Xing, Kong Beihua, Duan Tao (eds.); Lin Zhongqiu, Di Wen, Martin, Cao Yunxia, ​​Qi Hongbo (co-eds.). Obstetrics and Gynecology, 9th edition [M]. Beijing: People's Medical Publishing House, 2018

[2]NICEGuideline.Heavymenstrualbleeding(NG44).https://www.rcog.org.uk/en/guidelines-research-services/guidelines/heavy-menstrual-bleeding-nice-clinical-guideline-44/.

[3]DavisE,SparzakPB.AbnormalUterineBleeding.[Updated2023Sep4].In:StatPearls[Internet].TreasureIsland(FL):StatPearlsPublishing;2023Jan-.Availablefrom:https://www.ncbi.nlm.nih.gov/books/NBK532913/

[4]FraserIS,CritchleyHO,BroderM,MunroMG.TheFIGOrecommendationsonterminologiesanddefinitionsfornormalandabnormaluterinebleeding.SeminReprodMed.2011;29(5):383-390.doi:10.1055/s-0031-1287662.

This article is a work of Science Popularization China-Starry Sky Project

Produced by: Science Popularization Department of China Association for Science and Technology

Producer｜China Science and Technology Press Co., Ltd., Beijing Zhongke Xinghe Culture Media Co., Ltd.

Author: Doctor Fei Dao Duan Yu

Reviewer: Lan Yibing, deputy chief physician, Department of Obstetrics and Gynecology, Zhejiang University School of Medicine