X-rays are a form of high-energy, invisible electromagnetic radiation capable of penetrating solid objects, including the human body. Discovered by Wilhelm Röntgen in 1895, they revolutionized medical diagnostics by allowing clinicians to view internal structures without invasive surgery. In everyday midwifery and general medical practice, standard radiographs help confirm skeletal injuries, assess chest conditions, and evaluate foreign bodies. Understanding how these rays work forms the foundation of safe diagnostic imaging.
An X-ray machine relies on an evacuated glass tube containing a cathode and a anode. When high voltage is applied, electrons are accelerated from the heated cathode and crash into a heavy metal target, usually tungsten, at the anode. This sudden deceleration converts the kinetic energy of the electrons into high-energy photons—namely, X-rays—along with a large amount of thermal waste.
On the electromagnetic spectrum, X-rays sit between ultraviolet light and gamma rays, possessing short wavelengths and high frequencies. This high frequency is precisely what gives them the energy to pass through soft tissues.
When an X-ray beam passes through the human body, the photons experience different fates depending on the density of the tissue they encounter.
Interpreting a radiograph requires recognizing five basic radiographic densities on a grayscale: air, fat, soft tissue (or fluid), bone, and metal. Metal, such as surgical clips or jewelry, appears brightest white. Air appears black. Soft tissues and water share an intermediate gray shade, making it difficult to distinguish between muscle and fluid without clinical context. Midwives reviewing pelvic or chest films must systematically evaluate these shades to spot abnormalities like fractures, fluid overload, or free air in the abdomen.
Ionizing radiation carries biological risks, including cellular damage and increased long-term cancer susceptibility, because it can disrupt chemical bonds and DNA. In maternity care, safeguarding pregnant women and developing fetuses is an absolute priority. Midwives and radiographers adhere strictly to the ALARA principle—keeping exposure As Low As Reasonably Achievable.
Key safety measures include:
In busy Nigerian clinics and tertiary hospitals, X-rays remain a cost-effective and accessible diagnostic tool. Chest radiographs are routinely requested to evaluate persistent coughs, tuberculosis, and cardiac enlargement. In obstetric and gynecological emergencies, erect abdominal plates help detect free gas from a ruptured viscus or identify retained metallic foreign objects. Despite the rise of advanced imaging like ultrasound and MRI, the plain radiograph remains a frontline modality due to its speed and availability.