We've all got that one friend who only bleeds lightly for 2 days and then they’re done for the month. Frustrating isn't it?
But what about the rest of us? How long should our period last? What's a normal menstrual cycle and when should we be taking a trip to the doctor to talk about our periods?
How long do periods usually last?
Menstrual cycles happen once a month to prepare for a possible pregnancy. If a pregnancy doesn't occur then the uterine lining sheds and the period will start. A typical menstrual cycle is 28 days long and will occur around every 24-38 days. While periods usually last somewhere between 4-8 days, there isn't a definitive "normal period length." Each person is different, and cycles can vary each month [ 1 ] depending on a variety of factors.
Signs your period is too heavy, long, or irregular
It's important to remember that what's 'normal' for your friend, will be different for you. However, there are some things that tell us whether our periods aren't quite right and we need to speak to our doctor.
Each period, most women and people who menstruate will lose 60 milliliters (around 2.02 ounces) of blood, which is around 4 tablespoons. On average that means it would take 4 hours for a pad or tampon to become full. If a person is bleeding around 80 milliliters each period (around 2.70 ounces) they are considered to have heavy bleeding .
Physical signs of heavy periods include:
Heavy periods can have a huge impact on our emotional state too such as,:
It's important to recognize that heavy menstrual bleeding has a major impact on a person’s quality of life, and any interventions should aim to improve this rather than just focusing on blood loss.
If your periods are longer than 7 days on a regular basis then it's considered a long period and you should speak to a doctor , . Longer lasting periods are often referred to as menorrhagia, meaning someone is experiencing heavy periods. Around 1 in every 20 women and people who menstruate have menorrhagia .
If you experience different amounts of time in between your periods then they are irregular. Again, this may be normal for you, especially if you don't have any other period-related symptoms such as painful cramps, blood clots, or heavy bleeding, and doesn't necessarily mean there is a problem. It's especially common for younger teens to have irregular periods during the first 2-3 years after starting their period. It's also common for people entering perimenopause to experience irregular periods. Note that you can still get pregnant despite having irregular periods.
Practice guidelines published in Best Practice & Research Clinical Obstetrics & Gynecology found that between 14% and 25% of women and people who menstruate have abnormal uterine bleeding, including heavy menstrual bleeding .
Is it normal for periods to be short?
Menstrual period cycles can vary in length. For some, this is normal, for others, a trip to the doctor might be needed.
Birth control pills may cause bleeding in the first few weeks and it may take around 3 months for your periods to settle down. You may notice your periods are lighter when taking contraceptive pills as the lining of your uterus isn't as thick., .
There are a range of reasons why people experience lighter and shorter periods, these include :
4 factors that affect how long your period lasts
There are a number of factors that can affect how long your period may last for. These include:
1. Menstruation can change with age
Young people begin their period around the age of 8-12 years. When their periods first start they are likely to last around 5 days. During the first 2-3 years, it's common for the period to be irregular. After this, they will begin to arrive every 4-5 weeks and still only last for around 5 days . During the teenage years, it's common for periods to be heavier and can become lighter in your 20's and 30's, and the menstrual cycle will typically last between 24-38 days.
Entering perimenopause also has an effect on how regular the menstrual cycle is. Women and people who menstruate usually enter this stage in their lives around the age of 40.
2. Birth control's influence on the length of periods
All types of hormonal birth control can have an effect on the menstrual cycle, especially in the first 3-6 months of using it.
How long does a period last while on birth control?
When using the combined pill, the contraceptive patch, the contraceptive injection, and the vaginal ring, it stops an egg being released from the ovary. If you still have a monthly bleed, this may be lighter and is called a withdrawal bleed.
The birth control pill and period length
Whether taking a combined pill which contains estrogen and progestin, or a progestin-only pill, it's likely that you will experience breakthrough bleeding or spotting in the first few months.
If you're taking the progestin-only pill you may also spot if you forget to take the pill, even if it's a couple of hours difference. The pill works by stopping ovulation and preventing the male's sperm from reaching the egg .
It can take around three months for your periods to return to a regular pattern once you stop using the pill.
The birth control injection or implant and period length
The hormonal implant is a tiny tube that is placed underneath the skin in the arm. The tube releases progesterone which inhibits the pituitary gland, to stop the ovaries from releasing an egg. The most common side effect of the implant is light and irregular bleeding .
The injection contains progesterone and is given every 3 months. The injection stops the ovaries from releasing an egg and thickens the cervical mucus. The injection can cause irregular bleeding and may happen during the first few months of having the injection, but this may settle down as you have more injections .
The IUD and period length
The copper IUD may cause you to have irregular bleeding for 3-6 months and may cause heavier or longer periods .
The progestin IUD can also cause irregular bleeding for 3-6 months. This should improve over time, become lighter and may disappear . In fact, a significant number of women and people who menstruate no longer get their period while using a hormonal IUD.
The vaginal ring and period length
The vaginal ring is a flexible ring that is placed inside the vagina, it contains both estrogen and progesterone. You wear the ring for 3 weeks and then remove it to have a period during the 4th week. However, using the ring may cause irregular bleeding or spotting  within the first few months.
The emergency contraceptive pill and period length
Emergency contraception can change the timing of your next period. It may also cause spotting or irregular bleeding during the week or month after you've taken the pill .
3. Underlying health conditions and irregular periods
There are different health conditions that can cause irregular, heavy, or prolonged bleeding such as ,
If you think you may be experiencing any of the above, it's important to go and see your doctor.
4. Sexually transmitted infections (STI's) and irregular periods
Sexually transmitted infections such as chlamydia and gonorrhea can cause irregular bleeding and spotting between periods . Pelvic inflammatory disease is caused when a bacterial infection spreads from the vagina or the cervix to the reproductive organs. This infection can cause abnormal bleeding between periods, during and after sex, and heavy periods .
When to see a doctor about abnormal periods
Abnormal periods vary person to person. Below are some signs that your period is abnormal .
Solutions for long, heavy, or painful periods
Before trying to treat long or heavy periods, it's vital that you speak with your doctor or nurse first to rule out any health conditions and receive any necessary treatment.
If there are no obvious reasons for your long or heavy periods then the doctor may suggest you begin a form of contraception. At first, this may cause irregular bleeding or spotting. However, over time, this should settle and help your periods to fall into a regular pattern.
Not all women and people who menstruate wish to use contraception and may choose to look at other ways to manage their long or heavy periods such as:
If your doctor is in agreement, they may prescribe you the combined contraceptive pill. If you take your packets back-to-back, you will probably skip a period. However, one side effect of taking pill packets together can be unexpected bleeding.
The IUD and vaginal ring can also be used to delay or prevent a period.
The length of a period is unique to a person's body, however, there are factors that can influence menstruation, including health issues and birth control. If you notice any changes to your menstrual cycle or period then it's important to speak to your doctor.
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