What could be the reason for heavy and prolonged menstrual bleeding? How to treat functional uterine bleeding?

Author: Yu Qi, Chief Physician, Peking Union Medical College Hospital

Reviewer: Bai Wenpei, Chief Physician, Beijing Century Altar Hospital, Capital Medical University

Normal menstruation includes four basic elements:

First, the menstrual cycle is 21-35 days, with an average of 28 days;

Second, the length of menstrual period is ≤7 days, with an average of 4-6 days;

Third, the amount of menstrual bleeding, which was previously set at 5-80 ml, is now considered excessive menstrual bleeding that affects the quality of life as menorrhagia, and hypomenorrhea if the total amount of menstrual blood cannot soak through a daily sanitary napkin;

Fourth, menstrual blood is dark red in color and has a relatively viscous texture.

1. What could be the possible reasons for heavy menstrual bleeding and prolonged menstrual bleeding?

If menstruation is abnormal, with heavy bleeding, long bleeding time, and bleeding during non-menstrual periods, we call it abnormal uterine bleeding.

Abnormal uterine bleeding may be caused by organic disease or functional disorder.

Organic diseases, in simple terms, are inflammation, tumors, trauma, etc. These are probably the main causes. In addition, another reason is pregnancy.

For obstetricians and gynecologists, if they encounter a patient who has no menstruation or has continuous bleeding, they will immediately think about whether the person is pregnant, and they must first clarify this matter.

Of course, for obstetricians and gynecologists, what is more terrifying than pregnancy is ectopic pregnancy, which can also cause heavy bleeding and needs to be treated in a timely manner.

If a patient continues to bleed and factors that can cause abnormal uterine bleeding, such as pregnancy, ectopic pregnancy, tumors, injury, inflammation, etc., are ruled out, it is called dysfunctional uterine bleeding, or DUB for short.

2. What are the types of functional uterine bleeding?

Dysfunctional uterine bleeding can be divided into two main categories: ovulatory and anovulatory.

Why can there be successful bleeding without ovulation? Because there are eggs growing in the ovaries, but no ovulation. When the eggs grow, they can produce estrogen, which can make the endometrium thicker. However, if the grown eggs are not released, they will slowly shrink. Once they shrink, the estrogen level will drop, and then some small eggs will continue to grow, so the estrogen level will continue to fluctuate.

Fluctuations in estrogen levels can cause the endometrium to shed and cause bleeding. This bleeding cannot be stopped and will increase in volume, which is called anovulatory functional uterine bleeding.

Who is prone to anovulatory functional uterine bleeding? One is during adolescence, and the other is during menopause. Because during adolescence, the function of the hypothalamus-pituitary-ovarian axis is not well established, and during menopause, the function of this axis is almost gone, so it will cause functional disorders and anovulation.

We often see that children aged thirteen or fourteen are particularly prone to this condition. Continuous bleeding may lead to very severe anemia, which is very dangerous.

Figure 1 Original copyright image, no permission to reprint

Another category is ovulatory functional uterine bleeding. Ovulatory functional uterine bleeding can be divided into several situations:

The first type is that the menstrual flow is heavy, the cycle is very regular, and the bleeding time is within seven days. However, the amount of bleeding is particularly heavy every time the menstruation comes, especially in the first three or four days of the menstrual period. This situation is called menorrhagia.

Figure 2 Original copyright image, no permission to reprint

What is the main cause of menorrhagia? When the endometrium sheds and bleeds, the coagulation system in the body starts to slowly stop the bleeding. However, the small blood clots caused by the coagulation system cannot stay in the blood vessels for a long time. If the blood clots stay in the blood vessels for a long time, they will cause blood vessels to be blocked and there will be no blood supply in the future. Therefore, whenever the coagulation system is activated, there must be a fibrinolytic system to start and then dissolve the blood clots.

In some people, the fibrinolytic system is too powerful. It dissolves the small blood clots created by the coagulation system before they can stop the bleeding, so these people will bleed a lot.

In addition to menorrhagia, which is a type of functional uterine bleeding related to ovulation, there is also intermenstrual bleeding, which is vaginal bleeding when menstruation is not supposed to occur. This also involves many situations, such as poor corpus luteum function, incomplete corpus luteum atrophy, or ovulation bleeding. However, this type of bleeding is generally not very serious, just spotting, which will heal in a few days and generally does not require treatment. If the amount of ovulation bleeding is heavy and there are uncomfortable symptoms, active treatment is required.

3. How to treat dysfunctional uterine bleeding?

For adolescent girls with anovulatory functional uterine bleeding, two steps are generally taken: the first is to stop the bleeding, and the second is to control the cycle.

There are many ways to stop bleeding. The simplest and most suitable method is the contraceptive pill. The contraceptive pill can stop bleeding, but it does not solve the problem of anovulation. So she may have this situation every month in the future. What should I do? I have to control the cycle. The way to control the cycle is still to use contraceptive pills, so contraceptive pills are the simplest and most convenient method.

After stopping the bleeding, control the cycle for half a year, then stop the medication and see if she regains regularity on her own.

For menopausal women with anovulatory dysfunctional uterine bleeding who are over 40 years old, contraceptives are generally not used. Instead, progesterone is used to stop the bleeding and the cycle is also controlled. The method of controlling the cycle is cyclical progesterone, which is given for 10-14 days each month to control the menstrual cycle. This is also a common method.

As for menorrhagia, it is usually caused by hyperactivity of the fibrinolytic system, and antifibrinolytic drugs are also a method. There is also a contraceptive ring containing progesterone, which can also greatly reduce the amount of menstrual bleeding.

As for intermenstrual bleeding, if you want to have a child, you can use ovulation-stimulating drugs, and if you don't want to have a child, you can use contraceptive pills. So different situations require different drugs to treat.