Getting your period every two months, or roughly every 60 days, means your menstrual cycle is significantly longer than the typical 21-to-35-day range. The medical term for this is oligomenorrhea, defined as cycles longer than 35 days or fewer than 8 or 9 periods per year. It’s relatively common, and while it’s sometimes just a temporary blip caused by stress or a life transition, it can also signal an underlying hormonal issue worth investigating.
What a Normal Cycle Actually Looks Like
The average menstrual cycle lasts 28 days, but anything between 21 and 35 days is considered normal. That range exists because the first half of your cycle, when an egg is maturing, varies in length from person to person and even month to month. The second half, after ovulation, is more consistent at roughly 14 days.
When your cycle stretches to 60 days, it usually means something is delaying or preventing ovulation. Without ovulation, your body doesn’t get the hormonal signal to shed the uterine lining on schedule. Eventually it does shed, but much later than expected.
PCOS Is the Most Common Cause
Polycystic ovary syndrome (PCOS) is the single most common reason for consistently long cycles in people of reproductive age. It’s diagnosed when at least two of the following are present: signs of excess androgens (like acne, thinning hair, or excess body hair), irregular or absent ovulation, and a specific appearance of the ovaries on ultrasound.
In PCOS, higher-than-normal levels of androgens interfere with the egg’s development and release. Your body keeps trying to ovulate but can’t complete the process on time, so the cycle drags on for weeks. Cycles longer than 35 days, or fewer than 8 per year, are one of the hallmark patterns. If your periods have been infrequent for a while and you also notice breakouts along the jawline, hair growth on your chin or chest, or difficulty losing weight, PCOS is worth discussing with your doctor.
Thyroid Problems and Prolactin Imbalances
Your thyroid gland has a surprisingly strong influence on your cycle. Both an underactive and overactive thyroid can lead to infrequent periods. An overactive thyroid raises levels of a protein that binds to estrogen in the blood, which throws off the delicate hormonal feedback loop that triggers ovulation. An underactive thyroid slows everything down, including the signals between your brain and ovaries.
Prolactin, the hormone responsible for milk production, can also be a culprit. Even outside of pregnancy and breastfeeding, prolactin levels sometimes rise due to certain medications, a small benign growth on the pituitary gland, or other causes. Moderately elevated prolactin typically causes oligomenorrhea, with cycles spacing out just as you’re describing. Higher levels can stop periods altogether. Both thyroid issues and elevated prolactin are detected with simple blood tests and are very treatable.
Stress, Weight, and Energy Balance
Your brain is constantly monitoring whether conditions are favorable for a potential pregnancy, even if pregnancy is the last thing on your mind. When the answer is “not right now,” it dials down the hormonal signals that drive ovulation.
Chronic psychological stress is one of the strongest triggers. Elevated cortisol, your body’s primary stress hormone, directly suppresses the brain signal that kicks off each cycle. This isn’t about having a stressful week. It’s the kind of sustained pressure that comes from months of sleep deprivation, relationship turmoil, grief, or work burnout. Research on people with stress-related cycle loss shows they have a heightened cortisol response even to mild physical or emotional challenges, suggesting their stress system is stuck in overdrive.
Body weight plays a role at both extremes. In one study of adolescents, every single participant with a BMI in the overweight range (25 to 29.9) had infrequent cycles, while about 75% of those with a BMI in the normal range had regular periods. Being significantly underweight disrupts cycles too, because your body interprets low body fat as a sign of insufficient resources.
Exercise and Under-Fueling
If you exercise intensely without eating enough to match your energy output, your reproductive system is one of the first things your body deprioritizes. This isn’t limited to elite athletes. It happens to recreational runners, dancers, and anyone in a sustained caloric deficit.
The threshold researchers have identified is an energy availability below 30 calories per kilogram of fat-free body mass per day. In practical terms, that means the calories left over after subtracting what you burn during exercise aren’t enough to support basic body functions. At that level, your brain reduces the hormonal drive for ovulation, and periods become infrequent or stop entirely. The healthy target is around 45 calories per kilogram of fat-free mass. If your periods became irregular after ramping up training or cutting calories, the connection is likely not a coincidence.
Perimenopause and Other Life Stages
If you’re in your mid-to-late 40s, longer cycles are a hallmark of perimenopause, the transition phase leading up to menopause. This transition lasts an average of four years, though it can range from two to eight. During this time, you may not ovulate every month. Periods can space out, come closer together, be heavier or lighter, or disappear for a few months before returning. Skipping a month or two and then getting a period again is completely typical of this stage.
Irregular cycles are also common and expected in the first couple of years after your very first period. Teens often go 45 to 60 days or longer between cycles while their hormonal system is still maturing. This usually resolves within two to three years of menarche without any treatment.
Signs That Need Attention
An occasional long cycle, especially during times of stress, illness, or travel, is rarely cause for alarm. But certain patterns alongside infrequent periods deserve a closer look. Pay attention if your period lasts longer than 7 days when it does arrive, if you’re soaking through a pad or tampon every one to two hours, or if you feel dizzy or faint from blood loss. These point to abnormally heavy bleeding that may need treatment regardless of what’s causing the spacing.
If your cycles have been consistently longer than 35 days for several months and you’re not in your early teens or late 40s, it’s worth getting a basic workup. That typically involves blood tests checking thyroid function, prolactin, and androgen levels, along with a conversation about your stress, weight, exercise habits, and any medications you take. In many cases, the cause is identifiable and manageable once someone actually looks for it.