A back injury can affect the regularity and characteristics of a menstrual cycle. The connection is not always direct, but involves a combination of physical and physiological factors. The body’s network of nerves, its response to the stress of an injury, and medications used for treatment can all play a part in altering your period.
The Connection Between Nerves and Pelvic Function
Your spine houses the nerves that control many bodily functions, including those of the pelvic organs. The nerves that supply the uterus and ovaries emerge from the lower back, specifically the thoracolumbar (T12-L2) and lumbosacral (L4-S3) regions of the spine. An injury in this area, such as a herniated disc or inflammation, can physically compress or irritate these nerves.
This nerve interference can disrupt the signals between your brain and reproductive organs, affecting the hormonal cascade that governs ovulation and the uterine lining. Consequently, this may lead to irregular cycles, a missed period, or changes in menstrual pain.
In some cases, the compression of specific nerve roots can lead to symptoms that mimic other conditions. For example, compression of the sacral nerves can cause pain that radiates down the leg, a symptom often associated with sciatica.
The Body’s Systemic Response to Injury
A significant back injury is a major physical stressor that activates the hypothalamic-pituitary-adrenal (HPA) axis, the body’s primary stress response system. This leads to the release of stress hormones, most notably cortisol.
Elevated cortisol levels can interfere with the reproductive hormones that govern the menstrual cycle, such as estrogen and progesterone. This hormonal disruption can suppress or delay ovulation, leading to an irregular or missed period.
A back injury also initiates a systemic inflammatory response, releasing chemicals called cytokines to aid in healing. These circulating cytokines can also interfere with the hormonal balance required for a regular menstrual cycle.
Influence of Pain Management and Medication
The medications used to manage back pain can also influence your menstrual cycle. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, are a common treatment for back pain. These drugs work by inhibiting the production of prostaglandins, which are compounds that cause inflammation and pain.
Prostaglandins also play a part in menstruation by causing the uterine contractions that help shed the uterine lining. By reducing prostaglandin levels, NSAIDs can lessen the intensity of these contractions, which may result in a lighter or delayed period. This effect is usually temporary.
Other types of pain medication, such as muscle relaxants or opioid painkillers, can also have side effects that impact the menstrual cycle. These medications can affect the central nervous system and hormonal regulation, potentially leading to menstrual irregularities.
When to Seek Medical Advice
While temporary menstrual changes can occur after a back injury, certain symptoms warrant a consultation with a healthcare provider to get an accurate diagnosis.
You should seek medical advice if menstrual irregularities persist for more than two or three cycles. The sudden onset of severe and debilitating period pain that is not typical for you also warrants a medical evaluation. If you miss a period and pregnancy is not a possibility, it is a good idea to speak with a doctor.
Pay close attention to any accompanying neurological symptoms. Numbness or weakness in the legs, or any changes in bowel or bladder control, are considered red-flag symptoms and require immediate medical attention. These could indicate a more serious spinal issue that needs urgent evaluation.