Diagnostic Approach to Back Pain in Pregnant Women

Introduction to Back Pain in Pregnancy

The American College of Obstetricians and Gynecologists recommends that back pain in pregnant women be categorized into three main groups: non-specific low back pain (85% of cases), pain with radiculopathy or spinal stenosis, or pain associated with a specific spinal cause requiring urgent evaluation 1, 2

The American College of Physicians suggests that the essential history should include characteristics of the pain, such as location, frequency, duration, intensity, and history of back pain before pregnancy 1, 3
The American Journal of Obstetrics and Gynecology reports that the prevalence of low back and pelvic pain peaks at 6 and 7 months of gestation 4, 5
The Annals of Internal Medicine recommends evaluating the response to previous treatments and their effectiveness 1, 3

The American College of Physicians identifies signs of infection or malignancy, such as fever, unexplained weight loss, or history of cancer, as red flags that increase the post-test probability of cancer from 0.7% to 9% 1
The Annals of Internal Medicine notes that progressive neurological deficits, such as motor weakness at multiple levels, fecal incontinence, or urinary dysfunction, are red flags that require urgent evaluation 1, 2

The American Journal of Obstetrics and Gynecology suggests that abdominal pathologies, such as pancreatitis, nephrolithiasis, or aortic aneurysm, should be considered as potential causes of referred pain 1, 3
The Journal of the American College of Radiology reports that appendicitis is the most common non-obstetric surgical condition in pregnant women, occurring in 1 in 20 women of childbearing age 6

The American Journal of Obstetrics and Gynecology explains that the physiopathological mechanisms of non-specific low back and pelvic pain include ligamentous laxity, reduced ligament stiffness, and increased demand on stabilizing muscles 5, 7
The American Journal of Obstetrics and Gynecology notes that the prevalence of low back pain occurs in up to two-thirds of pregnancies, and pelvic girdle pain occurs in approximately 20% of pregnancies 4, 5, 7

The Annals of Internal Medicine describes the clinical signs of sciatica, pseudoclaudication, and motor deficits as indicative of radiculopathy or spinal stenosis 1, 2, 3

The Annals of Internal Medicine reports that cancer, fracture, infection, and cauda equina syndrome are specific spinal causes that require urgent evaluation, although they are rare 1, 8, 9

The Journal of the American College of Radiology recommends ultrasound as the primary imaging modality for evaluating abdominal and pelvic causes of referred pain 6, 10
The Journal of the American College of Radiology suggests that MRI is the safest modality for investigating low back pain during pregnancy and should be used as a second-line imaging modality after ultrasound to avoid radiation exposure 6, 10

The Annals of Internal Medicine emphasizes the importance of evaluating psychosocial factors, as they predict the risk of chronic disabling back pain 1, 2, 3
The American Journal of Obstetrics and Gynecology notes that severe cases of low back and pelvic pain are associated with sleep disturbances, altered daily activities, and depression 4, 5

The American Journal of Obstetrics and Gynecology warns against underreporting of low back and pelvic pain by patients, requiring active questioning by healthcare providers 4, 5
The Annals of Internal Medicine cautions against missing red flags that require urgent evaluation and neglecting psychosocial evaluation, as these factors contribute significantly to pain perception 1, 3

The American College of Radiology recommends palpation of spinous processes, gait assessment, and range of motion testing as part of the physical examination priorities for pregnant women with back pain 11

The American College of Radiology suggests that imaging is not routinely necessary for pregnant women with isolated back pain and no red flags, and that MRI without gadolinium is the safest modality for spinal evaluation when imaging is necessary 11

The American College of Radiology advises against routine imaging without red flags, as it wastes resources and provides no benefit 11