Menstruation is a woman’s monthly bleeding, often called your “period.” When you menstruate, your body discards the monthly buildup of the lining of your uterus (womb). Menstrual blood and tissue flow from your uterus through the small opening in your cervix and pass out of your body through your vagina.
During the monthly menstrual cycle, the uterus lining builds up to prepare for pregnancy. If you do not get pregnant, estrogen and progesterone hormone levels begin falling. Very low levels of estrogen and progesterone tell your body to begin menstruation.
Your menstrual cycle is counted from the first day of your period up to the first day of your next period. Your hormone levels (estrogen and progesterone) usually change throughout the menstrual cycle and can cause menstrual symptoms.
Your menstrual cycle may vary from 21 to 35 days long. Most periods last 3 to 5 days, but anywhere from 2 to 7 days is normal. Menstrual cycles may start around the same date every month or they may be irregular. The changing hormone levels as well as the use of certain medications can affect your menstrual cycle and other health problems.
What is a late or missed period?
A late period means that it has not started 5 or more days after the day you expected it to start. A missed period means that you have had no menstrual flow for 6 or more weeks after the start of your last period.
If your period is a few days late, it typically is not a cause for concern. But a period that’s a few weeks late may indicate an underlying condition. If you don’t have any known condition affecting your menstrual cycle, your period should start within 21 to 35 days of your last period, depending on your normal cycle.
List of medications that can cause late or missed period
There are several prescription and over-the-counter medications including supplements that can interact with your hormones and cause late or missed periods, these include:
Levothyroxine
Levothyroxine is used to treat hypothyroidism (a condition where the thyroid gland does not produce enough thyroid hormone). It is also used with surgery and radioactive iodine therapy to treat thyroid cancer. Levothyroxine is in a class of medications called hormones. It works by replacing thyroid hormone that is normally produced by the body.
Without thyroid hormone, your body cannot function properly, which may result in poor growth, slow speech, lack of energy, excessive tiredness, constipation, weight gain, hair loss, dry, thick skin, increased sensitivity to cold, joint and muscle pain, heavy or irregular menstrual periods, and depression. When taken correctly, levothyroxine reverses these symptoms. However, taking levothyroxine can cause irregular menstrual periods in women.
Aspirin
Aspirin is in a group of medications called salicylates. It works by stopping the production of certain natural substances that cause fever, pain, swelling, and blood clots. Aspirin is also available in combination with other medications such as antacids, pain relievers, and cough and cold medications. Studies have shown that high doses (3,000 mg daily for 20 days starting cycle day 5) are associated with a shortening of the menstrual cycle.
Rifampicin
Rifampicin, also known as rifampin, is an ansamycin antibiotic used to treat several types of bacterial infections, including tuberculosis, Mycobacterium avium complex, leprosy, and Legionnaires’ disease. Rifamycins interfere with bacterial DNA-dependent RNA polymerase and are potent bactericidal agents. Rifampin and its analogs kill actively multiplying extracellular organisms, intracellular mycobacteria, and semi-dormant mycobacteria in tissues. However, rifampin has been shown to have some effect on menstrual cycles by causing abnormal bleeding, the complete absence of periods, or increased time between periods.
Blood Thinners
Blood thinners are medicines that help blood flow smoothly through your veins and arteries. They keep blood clots from forming or getting bigger. They’re used to treat some types of heart disease and heart defects, along with other conditions that could raise your risk of forming dangerous clots.
These drugs help protect against heart attacks and strokes. But they also come with risks: For example, they’ll cause you to bleed more than usual if you cut yourself. The most commonly prescribed blood thinner is warfarin. Newer types of anticoagulants are also available and are becoming increasingly common.These include: rivaroxaban (Xarelto), dabigatran (Pradaxa), apixaban (Eliquis) and edoxaban (Lixiana).
Most times blood thinners or anticoagulants do not affect the duration of your period, but they can increase the flow of blood and slightly increase the chance of passing clots during your period. For example, you are likely to bleed more easily than normal while taking apixaban (Eliquis). The kind of bleeding you might have includes periods that are heavier and last longer than usual.
Nonsteroidal anti-inflammatory drugs (NSAIDs)
Non-steroidal anti-inflammatory drugs (NSAIDs) are medicines that are widely used to relieve pain, reduce inflammation, and bring down a high temperature. They’re often used to relieve symptoms of: headaches. painful periods. sprains and strains. Non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen (for example, Advil or Motrin) and naproxen (for example, Aleve) can make a woman may experience less bleeding during her period.
Nevertheless, NSAIDs reduce prostaglandin levels, which are elevated in women with excessive menstrual bleeding. It was suggested that they might help with heavy bleeding and may have a beneficial effect on painful menstrual periods.
Hormonal contraceptives
Hormonal contraceptives contain estrogen and progesterone, or progesterone only. They prevent pregnancy by blocking the release of eggs from the ovaries, thinning the lining of the uterus, or thickening the mucus in the cervix to help keep sperm from reaching the egg. While on hormonal contraceptives, some women may experience a lighter period while others may find that their period stops. This occurs because the medication works by introducing different hormones into your system which alters your menstrual cycle.
Hormone replacement therapy
Hormone replacement therapy is a medication that contains female hormones. You take the medication to replace the estrogen that your body stops making during menopause. Hormone therapy is most often used to treat common menopausal symptoms, including hot flashes and vaginal discomfort.
Hormone replacement therapy can cause irregular bleeding or spotting during the first 4-6 months, especially among those continuously taking combined HRT or Tibolone.
Chemotherapy
Chemotherapy is a cancer treatment where medicine is used to kill cancer cells. There are many different types of chemotherapy medicine, but they all work in a similar way. They stop cancer cells from reproducing, which prevents them from growing and spreading in the body. In women, some chemotherapy drugs can cause significant damage to the ovaries and stop regular menstrual cycles (amenorrhea). The good news is that for women under the age of 40, this is often temporary and periods will start again. However, in women over 40, it’s more often permanent and results in the early onset of menopause.
