It’s common for periods to occasionally be longer or shorter than usual. But if your periods are longer than 38 days, it’s considered a long menstrual cycle, also called oligomenorrhea. There are a few potential causes behind long periods:
Hormonal imbalances
Hormonal imbalances are a common cause of long periods. Here are some specific hormonal issues that can lead to longer menstrual cycles:
- Polycystic ovary syndrome (PCOS): This condition causes the ovaries to produce higher-than-normal amounts of androgens like testosterone. The hormonal imbalance interferes with ovulation.
- Hyperprolactinemia: Elevated levels of the hormone prolactin can inhibit ovulation and cause irregular periods.
- Thyroid disorders: Both hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid) can lead to irregular cycles and amenorrhea (lack of periods).
- Premature ovarian failure: This causes the ovaries to stop functioning normally before age 40. It leads to low estrogen levels and missed periods.
Medications
Certain medications and therapies can potentially cause menstrual irregularities like long cycles:
- Birth control pills: When you first start the pill, it may lead to light, irregular bleeding at first. This normally resolves within a few months.
- Depot medroxyprogesterone acetate (DMPA): This birth control injection can cause prolonged bleeding for some women, especially in the first 6-12 months of use.
- Antidepressants: Drugs like SSRIs may increase prolactin levels and lead to oligomenorrhea.
- Chemotherapy: Cancer treatments can damage the ovaries and cause fluctuations in hormone levels.
Perimenopause
As women approach menopause, usually in their mid to late 40s, periods often become irregular. This transitional time leading up to menopause is called perimenopause. Some things that happen include:
- Periods become further apart
- Menstrual flow might be lighter or heavier
- Cycles may be longer or shorter
- Ovulation may not occur every cycle
These changes are normal and expected as women near the end of their reproductive years. But very long cycles (over 3 months apart) should still be evaluated during the perimenopause transition.
Stress
Physical or emotional stress can interfere with hormonal balances and ovulation. For example, high stress levels lead to increased cortisol secretion. Cortisol inhibits the body’s release of hormones needed for ovulation, which can lead to long and irregular menstrual cycles.
Sudden weight loss or excessive exercise
The female body requires adequate energy stores and body fat levels to ovulate and menstruate properly. Women who lose large amounts of weight quickly through dieting, eating disorders, or excessive amounts of exercise may notice their periods become infrequent or absent altogether.
Anatomical problems
Certain anatomical problems in the reproductive system can cause menstrual irregularities like long cycles:
- Asherman’s syndrome: Scarring in the uterine cavity, often from injury caused by dilation and curettage (D&C). This can lead to light, infrequent periods.
- Endometrial polyps or fibroids: These benign growths in the uterus may lead to light, irregular periods if they grow large enough.
- Congenital anomalies: Birth defects affecting the reproductive tract, like an absent uterus or vagina, can also cause missing or irregular periods.
Primary ovarian insufficiency
Primary ovarian insufficiency describes when a woman’s ovaries stop functioning normally before she turns 40. It’s sometimes called premature ovarian failure. The reduced ovarian function leads to lower estrogen levels and irregular or missed periods.
Pelvic inflammatory disease
Pelvic inflammatory disease (PID) refers to inflammation of the female reproductive organs, usually from a sexually transmitted bacterial infection. PID can damage the ovaries and fallopian tubes, leading to infertility and irregular bleeding.
High prolactin levels
High blood levels of the hormone prolactin can interfere with ovulation by inhibiting the release of key reproductive hormones FSH and GnRH. This leads to irregular cycles.
Thyroid disease
Both hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid) can cause menstrual irregularities. Thyroid hormones directly impact reproductive hormone levels.
Premature menopause
Premature menopause, also called premature ovarian insufficiency, refers to menopause occurring before age 40. It’s linked to long, infrequent menstrual cycles and is usually tied to genetic factors or autoimmune disease.
Conclusion
In summary, long menstrual cycles can stem from hormonal problems, perimenopause, medications, stress, excessive weight loss, anatomical abnormalities, pelvic infections, thyroid issues, and more. See your doctor for proper diagnosis and treatment if you experience this. Treating any underlying condition can often restore normal menstrual cycles.
| Cause | Description |
|---|---|
| Hormonal imbalances | PCOS, thyroid disorders, elevated prolactin levels, etc. can impact cycles |
| Medications | Birth control, antidepressants, chemotherapy |
| Perimenopause | Irregular cycles are common as women near menopause |
| Stress | Physical or emotional stress affects hormone levels |
| Weight loss/exercise | Dramatic weight loss or too much exercise can lead to missing periods |
| Anatomical problems | Uterine scarring, polyps, congenital anomalies |
| Pelvic infections | PID can damage reproductive organs |
| High prolactin | Prolactin inhibits hormones needed for ovulation |
| Thyroid disease | Impacts reproductive hormone levels |
| Premature menopause | Ovarian failure before age 40 |
When to see a doctor
See your doctor if:
- Periods occur more than 3 months apart
- Periods were regular but became very irregular
- Periods were absent for several months and then return
- You have symptoms like facial hair growth, acne, and hair loss along with long cycles
- You’re under age 45 and think you may be in perimenopause
Tracking your cycles and being aware of what’s normal for your body can help identify when it’s time to be evaluated. The doctor can check for any underlying problems and offer solutions to restore regular menstrual cycles.
Diagnosing long periods
To get to the root of long cycles, your doctor will typically:
- Ask about your medical history and symptoms
- Conduct a pelvic exam
- Order hormone tests to check levels of:
- Estrogen
- Progesterone
- Testosterone
- DHEA
- Prolactin
- FSH
- TSH
- Check your glucose/insulin levels to assess for prediabetes or PCOS
- Perform an ultrasound to look at your reproductive organs
- Assess for any anatomical problems or pelvic infections
Treating long periods
Treatment aims to address any underlying problem causing the long cycles. Options may include:
- Hormonal birth control to regulate cycles
- Metformin or IVF drugs for infertility from PCOS
- Thyroid medication for hypothyroidism
- Medication to lower prolactin levels if elevated
- Surgery to remove uterine fibroids or polyps if they cause abnormal bleeding
- Antibiotics for pelvic inflammatory disease
- Lifestyle changes like stress and weight management
- Estrogen therapy for low estrogen levels
If a clear cause can’t be identified, the doctor may prescribe cyclic progesterone or birth control pills to induce regular menstrual bleeding every few months.
When to worry about long periods
While long cycles are usually not harmful in younger women, they can sometimes signal underlying health issues that need medical attention. So it’s important to follow up with your doctor.
Also note that longer menstrual cycles may make it harder to get pregnant. The less frequent ovulation gives you fewer chances to conceive each year. If you’re trying to have a baby without success after 6 months of long cycles, see your doctor for fertility testing.
In women over age 45, very irregular cycles could potentially be a sign of uterine cancer in rare cases. So it’s recommended to report postmenopausal bleeding or unusual discharge to your physician right away.
Tracking your cycles
To identify irregularities, it helps to keep track of when your period starts each month. There are a few ways to monitor your cycles:
- Use a paper calendar to note the start date each month
- Use period-tracking apps like Flo, Clue, or Eve to log your cycles
- Make notes about flow, painful or unusual symptoms, mood changes
- Record your cycles for at least 3-6 months to identify patterns
Pay attention to cycle length, duration of bleeding, and other details. Then you can identify any changes and notify your doctor about long cycles or missed periods.
Causes of long periods by age
Some of the potential causes of longer menstrual cycles differ based on a woman’s age. Here is an overview:
Teens
- PCOS
- Thyroid problems
- High stress levels
- Medications
- Rapid weight loss
- Intense athletic training
- Anatomical defects
20s and 30s
- PCOS
- Hypothyroidism
- Hyperprolactinemia
- Medications like antidepressants
- PID
- Perimenopause (may start in 30s)
40s
- Perimenopause
- Impending menopause
- Uterine fibroids
- Endometrial polyps
- Hormonal imbalances
- Stress
By better understanding what may lead to longer cycles at different life stages, you can work with your doctor to explore the most likely causes and solutions.
Preventing prolonged periods
It’s not always possible to prevent longer menstrual cycles if they are tied to an underlying medical condition. However, a few general tips can support regular, healthy periods:
- Eat a nutritious diet and stay hydrated
- Exercise regularly at moderate intensity
- Aim for a healthy BMI
- Find ways to manage stress effectively
- Limit alcohol intake
- Don’t smoke cigarettes
- Take steps to prevent PID through safe sex practices
- Discuss your medications with your doctor
Additionally, see your gynecologist for routine well-woman visits so any problems that could interfere with normal menstruation can be caught early. Being proactive helps maintain regular monthly periods.
When to see a doctor
Consult your physician if you experience any of the following:
- Menstrual cycles longer than 38 days
- Periods that were regular but became very irregular
- Three months in a row without a period
- Periods return after several months without one
- You’re under 45 and think you may be in perimenopause
- Symptoms like facial hair growth along with irregular cycles
Keeping track of your menstrual cycles helps identify changes that may require medical evaluation. Your doctor can get to the root of longer periods and offer appropriate treatment.