Missing your period can be concerning, especially if you’re not trying to conceive. Many women experience a late period at some point in their lives. While pregnancy is often the first thought, there are numerous other reasons why your menstrual cycle might be delayed. Understanding these potential causes can help ease anxiety and guide you on when to seek medical advice.
A typical menstrual cycle is around 28 days, but anything between 21 to 35 days is considered normal. A period is generally considered late if it hasn’t started within 35 days from the beginning of your last period. Obstetrician-gynecologist Dr. Karen Carlson explains that experiencing a cycle longer than 35 days warrants attention. Occasional irregularities are common, but consistently missing periods for months could indicate an underlying health issue.
Hormonal fluctuations and various health conditions are frequently behind irregular or late periods, besides pregnancy, breastfeeding, and menopause. Let’s explore some common reasons for a delayed period:
Common Reasons for a Late Period
1. Medications and Contraceptives
Certain medications, particularly hormonal birth control, can significantly affect your menstrual cycle. Dr. Carlson notes that “Contraceptive use like birth control pills can cause irregular bleeding.” Birth control pills work by regulating hormones to prevent ovulation, and this can sometimes lead to changes in your period, including delays or lighter bleeding. Similarly, other medications, including some antidepressants, antipsychotics, chemotherapy, and radiation therapy, can also disrupt your cycle.
It’s also common to experience irregular periods after stopping birth control pills or having an intrauterine device (IUD) removed. It can take a few months for your body to re-establish its natural hormonal rhythm and for regular menstruation to resume.
2. Body Weight Fluctuations
Your body weight plays a crucial role in hormone regulation, which directly impacts your menstrual cycle. Dr. Carlson emphasizes that “Low or high body weight can impact menstrual cycles.” Extreme weight loss, often associated with eating disorders like anorexia nervosa and bulimia nervosa, can lead to periods becoming irregular or stopping altogether. These conditions can severely disrupt the hormonal balance necessary for ovulation and menstruation.
Conversely, being significantly overweight or obese can also cause hormonal imbalances and menstrual irregularities. Excess body fat can affect estrogen production, leading to irregular or missed periods.
Even individuals with low body fat due to intense physical activity, like marathon runners or professional dancers, can experience menstrual changes. Dr. Carlson points out that “Cross-country runners or someone who does rigorous ballet training may have deficient body fat, which can cause people to stop menstruating.” This is because the body may not have enough energy reserves to support both intense activity and regular menstruation.
3. Stress Levels
Stress, both physical and emotional, is a significant factor that can disrupt your menstrual cycle. Dr. Carlson states that stress “can make people stop ovulating and thus have irregular menstrual cycles.” When you experience stress, your body activates the stress response, which can impact the hypothalamus – a part of the brain that regulates your hormones, including those responsible for your menstrual cycle.
Chronic stress, stemming from daily pressures, work demands, or personal challenges, can particularly affect your hypothalamus. This disruption can lead to hormonal imbalances that cause ovulation to become irregular or cease altogether, resulting in a late or missed period. Managing stress through relaxation techniques, exercise, or mindfulness can often help regulate your cycle.
4. Hormone Imbalances and Medical Conditions
Various hormonal imbalances and underlying medical conditions can lead to irregular or absent periods. Dr. Carlson highlights conditions like “polycystic ovary syndrome, or PCOS, thyroid issues, and pre-mature menopause…can make periods unpredictable or stopped.”
Polycystic Ovary Syndrome (PCOS) is a common hormonal disorder that affects women of reproductive age. It is characterized by hormonal imbalances, including an excess of androgens (male hormones), which can interfere with ovulation and lead to irregular periods, as well as other symptoms like acne and excess hair growth.
Thyroid disorders, whether hypothyroidism (underactive thyroid) or hyperthyroidism (overactive thyroid), can also disrupt your menstrual cycle. The thyroid gland plays a vital role in regulating metabolism, and thyroid hormones interact with other hormones in the body, including those involved in menstruation. An imbalance in thyroid hormones can therefore lead to period irregularities.
Premature menopause, also known as primary ovarian insufficiency, occurs when the ovaries stop functioning normally before the age of 40. This condition leads to a decrease in estrogen production and the cessation of ovulation and menstruation.
5. Uterine Scarring
In less common cases, uterine scarring can be a reason for a late or missed period. Dr. Carlson mentions that “menstrual cycles can also be disrupted or halted due to uterine scarring.” Uterine scarring, also known as Asherman’s Syndrome, can occur after certain gynecological procedures, most commonly a dilation and curettage (D&C).
A D&C is a procedure that involves scraping tissue from the uterine lining. In some instances, this can lead to the formation of scar tissue within the uterus. This scarring can prevent the normal thickening and shedding of the uterine lining, which is necessary for menstruation, leading to absent or very light periods.
When to Seek Medical Advice
While occasional late periods can be normal, it’s important to know when to seek medical attention. If your period is consistently late, if you’ve missed periods for three months or more, or if you experience other concerning symptoms alongside a late period, it’s advisable to consult with a healthcare professional. Dr. Carlson recommends calling 800.922.0000 to schedule an appointment with an OB-GYN if you have concerns about irregular periods or if your period is more than 35 days late. They can help determine the underlying cause and recommend appropriate management or treatment.
