Amenorrhea means having no menstrual periods. It is usually checked when periods stop for three months in a row (or six months if they were irregular), or when periods have not started by age 15. Pregnancy is the most common cause; others include stress, weight change, intense exercise, PCOS, thyroid or prolactin problems and early menopause.
- Primary
- No first period by age 15
- Secondary
- Periods stop for 3–6 months
- First test
- Pregnancy test
- Common tests
- Ultrasound, hormone blood tests
- Treatment
- Depends on the cause
- Seen by
- Dr. Sun-Ok Lee, OB-GYN specialist
What counts as amenorrhea?
Amenorrhea is the absence of menstrual periods during the years when they would normally occur. Doctors describe two types:
- Primary amenorrhea — periods have not started by age 15, or within a few years of breast development.
- Secondary amenorrhea — periods stop for three months in a row in someone who had regular cycles, or for six months in someone whose cycles were irregular.
Not having a period is expected during pregnancy, while breastfeeding, after menopause and with some hormonal contraceptives such as the hormonal IUD. If your cycle has simply become unpredictable rather than absent, see irregular periods.
What are the common causes?
| Cause | What happens | Typical clues |
|---|---|---|
| Pregnancy | Ovulation and periods pause | Positive pregnancy test, breast tenderness, nausea |
| Hypothalamic (stress, low weight, intense exercise) | The brain lowers the hormone signals to the ovaries | Recent weight loss, heavy training, major stress, travel or shift work |
| Polycystic ovary syndrome (PCOS) | Ovulation becomes infrequent | Acne, extra hair growth, irregular cycles since teens |
| Thyroid or prolactin problems | Hormone imbalance disrupts ovulation | Fatigue, weight change, milky nipple discharge |
| Primary ovarian insufficiency or menopause | The ovaries produce fewer eggs and less estrogen | Hot flushes, night sweats, vaginal dryness |
| Uterine scarring (Asherman’s syndrome) | Scar tissue prevents the lining from building up | Previous D&C or uterine surgery |
| Medications and contraception | Hormones or other drugs suppress bleeding | Hormonal IUD, injection, some psychiatric medications |
Several causes can overlap. Many are linked to wider hormonal imbalance, which is why testing usually looks at more than one hormone.
How is the cause diagnosed?
- Pregnancy test A urine or blood pregnancy test is always the first step, even if pregnancy seems unlikely.
- History in English Your doctor asks about your cycle history, weight, exercise, stress, medications, contraception, past surgery and symptoms such as acne, hair growth or hot flushes.
- Pelvic ultrasound A pelvic ultrasound on the same day checks the uterine lining and the ovaries, including signs of polycystic ovaries.
- Hormone blood tests Commonly thyroid function (TSH), prolactin, FSH, LH and estradiol, and androgens if PCOS is suspected. Some results take a few days.
- Further tests if needed A hormone challenge test, hysteroscopy for suspected scarring, or referral for brain imaging if prolactin is very high.
How is amenorrhea treated?
Treatment targets the underlying cause rather than the missing period itself:
- Lifestyle-related (hypothalamic) — restoring energy balance, adjusting training and addressing stress; hormone therapy may be considered to protect bone health.
- PCOS — cycle regulation with hormonal contraception or cyclic progestin, lifestyle support, and ovulation induction if pregnancy is wanted.
- Thyroid or prolactin problems — medication to correct the hormone level, often in coordination with an endocrinologist.
- Low estrogen (premature ovarian insufficiency) — hormone replacement to protect bones and heart health, and fertility counseling.
- Uterine scarring — hysteroscopic removal of adhesions.
If you are trying to conceive, ask about preconception counseling, because restoring ovulation is often part of the plan.
- No period for three months or more
- Unsure whether it is pregnancy, stress or hormones
- Worry about fertility and bone health
- Symptoms such as acne, hot flushes or nipple discharge
- Pregnancy ruled in or out on the same day
- Cause identified with ultrasound and hormone tests
- Treatment aims to restore cycles or protect health
- Clear explanation and English lab reports
When should you see a doctor?
Book a check-up if you have missed three periods in a row, your periods have not started by 15, or your cycles have become much longer than before. Earlier evaluation is sensible if you also notice nipple discharge, new headaches or vision changes, excess hair growth, hot flushes, or if you are trying to get pregnant.
Visiting Yoonho as an international patient
At Yoonho Women’s Hospital in Apgujeong, Seoul, an amenorrhea work-up usually starts with a consultation in English, a pregnancy test and an ultrasound on the same visit; blood test results are reviewed at a follow-up visit or shared by message. Bring a note of your last period dates and any medications. If you only need a pregnancy check, see pregnancy test and early ultrasound in Seoul.
Consultations are generally around ₩50,000–100,000 as a guide, with tests charged separately; a written estimate is given after consultation. NHI-enrolled residents are usually covered for medically necessary tests — see health insurance for foreigners.
Why international patients choose Yoonho
Frequently asked questions
How many missed periods should I wait before seeing a doctor?
Doctors usually evaluate amenorrhea after three missed periods in someone with previously regular cycles, or six months for irregular cycles. Take a pregnancy test first, and see a doctor sooner if you have other symptoms or want to conceive.
Can stress or moving to Korea stop my period?
Yes. Major stress, travel, jet lag, changes in diet or sleep and weight loss can temporarily suppress ovulation. If periods do not return within a few months, other causes should be checked.
Is it harmful not to have periods?
Not having a period is not dangerous in itself, but some causes involve low estrogen, which can weaken bones over time, and others such as PCOS may thicken the uterine lining. That is why the cause should be found.
Can I still get pregnant if I have amenorrhea?
It depends on the cause. Ovulation can return unpredictably, so contraception is still needed if you do not want pregnancy. If you want to conceive, treatment can often help restore ovulation.
Do I need an appointment?
Walk-ins are welcome during opening hours, but booking via WhatsApp or KakaoTalk helps reduce waiting time, especially if you would like blood tests on the same day.
OB-GYN Specialist · Director of OB-GYN
M.D., Ewha Womans University College of Medicine · Former Clinical Instructor, Ewha Womans University Mokdong Hospital · Member, Korean Society of Menopause
Last reviewed: . This page is for general information and does not replace an in-person consultation.
Talk to an English-speaking gynecologist
Yoonho Hospital · 304 Apgujeong-ro, Gangnam-gu, Seoul · Mon–Fri 9:00–18:00, Sat 9:00–13:00 · Walk-ins welcome.