A missed period can be stressful and frightening, and there’s nothing wrong with seeking out professional help just to be sure there’s nothing amiss. On average, most people get their periods every 28 days. But a healthy person’s menstrual cycle can last from 21 to 35 days.
As long as you are sure you are not pregnant and you feel well in yourself there is no need for concern if you miss one or two periods. If you don’t have a period for 3-6 months, or have other symptoms then you should consult a doctor. As you plan to see a doctor, you can also note these very common factors and see the one likely contributing to you missing your period.
Stress
Missing one period while going through a very stressful situation is common. Stress (physical and mental) is a common reason why someone might miss their period. Life events such as a vacation can cause a missed period as well, for likely the same physiological reasons as stress. Perhaps you’re just stressed from a big project or a big move, you’ve been sleeping very poorly, or maybe you’re just recovering from jet lag after a short vacation.
Stress affects the chemical messengers called hormones which are released from your brain. These hormones then go on to interrupt the production of gonadotropin-releasing hormone (GnRH)—a hormone that regulates ovulation and normally triggers your periods.
Weight Gain or Loss
Weight gain and weight loss can be reasons why a period is missed. Going too far in either direction can just be physically jarring for a body, and these sudden changes can prevent the body from having a normal period.
If you have an eating disorder called anorexia nervosa, losing too much weight can result in your periods stopping. It may also happen to athletes, gymnasts, long-distance runners and people who do an excessive amount of exercise.
Obesity influences estrogen and progesterone regulation and may even lead to issues with fertility. A detox diet, a new vigorous workout routine, or going from very active to sedentary can all be factors.
Polycystic Ovarian Syndrome (PCOS)
Polycystic ovarian syndrome, or PCOS, is a very common hormone disorder in women. Those with PCOS produce more androgen (a kind of sex hormone) than usual for a body with female reproductive organs, which can cause ovarian cysts, resulting in irregular periods . Without enough of the correct hormones to trigger ovulation it would be impossible to menstruate, hence a missed period. Women with PCOS may have other symptoms such as difficulty losing weight, spots (acne) and too much body hair.
Hormones Changes or Imbalance
A number of conditions which affect hormone levels may cause missed periods. Prolactin, a hormone that is known to stimulate the production of breast milk can be a problem. High prolactin levels can get in the way of a normal production of estrogen and progesterone, which can throw your ovulation and menstruation cycles off.
Another area of hormonal imbalance is with the thyroid gland. The thyroid is a gland that produces and releases hormones, and it interacts with your reproductive system to keep your ovulation and menstruation running on time. If you are producing either too much hormone (hyperthyroidism) or too little (hypothyroidism), your periods may be affected.
Breastfeeding
It is perfectly normal to have irregular periods and missed periods while you are breastfeeding, particularly if breastfeeding provides your baby with all or almost all of their calories. This is because the hormone that causes you to make milk, prolactin, also stops you from ovulating and having your period. No release of hormones means no ovulation can take place, and so you have no period. Some women may even experience spotting and irregular periods while you’re breastfeeding. It’s completely normal to have inconsistent cycles when you’re breastfeeding a baby.
Chronic diseases
Certain chronic illnesses such as celiac disease and diabetes can also affect your period. Blood sugar changes can affect hormones, and poorly controlled diabetes can lead to irregular periods.
Celiac disease is a disorder in the body that prevents the body from absorbing nutrients from food and often hurts the new intestine. Celiac is bad because it causes inflammation in the small intestine and prevents the body from absorbing vital nutrients, contributing to missed or late periods.
Medical treatment
It might seem a little strange , but certain medical treatments may cause delay or a missed period. A number of operations may result in absent periods. For example, after a hysterectomy (an operation where the womb is removed.), you will not have periods. As the blood during a period comes from the womb, you will never have periods again afterwards.
Another operation called endometrial ablation, which is sometimes done for heavy periods, also causes periods to stop. In this operation the lining of the womb is removed. This is not usually permanent and periods start again in time.
Treatments for cancer, such as radiotherapy or chemotherapy, can also damage the ovaries and result in absent periods. Recreational drugs such as heroin may also cause periods to stop.
Certain Drugs like Antidepressant and Emergency Contraception
Some medications, like anti-depressants, have been reported to cause some initial changes in periods. Examples are some medicines for schizophrenia (antipsychotic medicines), an anti-sickness medicine called metoclopramide and strong painkillers called opiates.
An emergency contraceptive could cause a missed period. An emergency contraceptive, like Plan B, contains the progestin hormone levonorgestrel, which is also in hormonal birth control. Levonorgestrel prevents ovulation, which can cause menstrual abnormalities.
Perimenopause and Menopause
Perimenopause is the period of transition between reproductive age and a non-reproductive age. Your periods may be lighter, heavier, more frequent, or less frequent during this time. In most cases, they’ll just be different than what you’re used to.
Early menopause can also lead to missing your period. If periods stop before the age of 40, this is very early and is said to be premature menopause. If periods stop between 40 and 45 years of age, it is called early menopause. At the menopause, periods stop.
No Reason at All
Maybe none of the above apply to you. You’re not stressed, have not made any significant lifestyle changes, your weight is unchanged, you’re not on birth control or any medications, and you don’t have any other conditions that could have an effect on your cycle. That’s totally normal as well.