When bleeding appears outside the expected period date, or comes around the time of a period but is light and stops within 1 to 2 days, it is not easy to tell whether it is a period or abnormal bleeding. In short, a normal period comes every 21 to 40 days and lasts about 3 to 7 days, bleeding outside that window should raise the suspicion of abnormal bleeding, and if the same symptom continues for 2 months or longer, testing is advisable. This article covers the differences between the two types of bleeding and their causes.
What does a normal period look like?
A normal menstrual cycle is between 21 and 40 days, and although it varies with a person's constitution and hormonal state, most periods show a regular pattern, returning at around the same time. Knowing how many days apart one's own periods come makes it possible to notice bleeding that falls outside the expected date, so the regularity of the cycle is the basic standard for identifying abnormal bleeding.
Bleeding in a normal period usually lasts about 3 to 7 days and becomes lighter as the days pass. The colour is also a clue: it starts out red and gradually turns a dark reddish brown as the period ends, so checking whether duration, amount and colour all follow this course helps in judging whether the bleeding is a normal period.
What kind of bleeding should make me suspect abnormal bleeding?
Abnormal bleeding is bleeding that occurs outside the normal period, and it can arise mainly from the uterus, cervix, ovaries, fallopian tubes or vagina. Even bleeding that overlaps with the expected period date can be light, more painful than usual, or stop within 1 to 2 days, so it is not easy to tell a period from abnormal bleeding by the cycle alone.
A short duration, a small amount and a bright red colour are described as the typical features of abnormal bleeding, but they do not appear in the same way in everyone. In some people the bleeding continues for 3 days or more, and patterns differ from person to person, so it is important to look at how irregular the timing, amount and duration are compared with the usual period.
- Duration — often brief, lasting about 1 to 2 days and then stopping
- Amount — often lighter than a usual period
- Colour — often bright red, unlike a period, which ends in a dark reddish brown
What causes abnormal bleeding?
Recurring abnormal bleeding should be regarded as a signal that something is wrong in the body, and possible causes include uterine conditions such as uterine fibroids, uterine polyps, endometriosis and endometrial hyperplasia, as well as hormonal imbalance and medication. Abnormal bleeding can also occur when ovulation is disrupted by immature follicles, as in polycystic ovary syndrome, so the menstrual cycle as a whole is reviewed.
When abnormal bleeding is caused by a problem in the uterus or ovaries, it can also affect a future pregnancy, so it is important to watch it carefully and manage it with appropriate treatment. If the same symptom continues for 2 months or longer, it is advisable to be tested to find the cause and, for the sake of early detection, to seek help from a medical team.
- Uterine conditions — uterine fibroids, uterine polyps, endometriosis and endometrial hyperplasia can be the cause
- Hormonal imbalance — when hormonal balance is disturbed, bleeding can occur outside the period as well
- Medication — a medicine currently being taken is sometimes suspected as the cause of abnormal bleeding