Cephalopelvic disproportion (CPD) is a medical condition that occurs when the baby's head or body is too large to pass safely through the mother's pelvis during childbirth. This condition can make vaginal delivery difficult or impossible, and may require a cesarean section (C-section) to deliver the baby.

CPD can be caused by several factors, including the size and shape of the mother's pelvis, the size and position of the baby, and medical conditions such as diabetes or obesity that can cause the baby to grow larger than average. CPD is typically diagnosed during labor when progress has stalled despite strong contractions, and the baby's head is not descending into the pelvis.

If CPD is suspected, the healthcare provider will typically perform a physical examination to assess the size and position of the baby and the shape and size of the mother's pelvis. Imaging tests such as ultrasound or X-ray may also be used to help make the diagnosis. If CPD is confirmed, the healthcare provider will discuss the risks and benefits of different delivery options with the mother and develop a plan for safe delivery.

Pelvimetry is a medical measurement and evaluation of the size and shape of the pelvis, which can be performed in several ways:

1. Clinical pelvimetry: This involves physical examination to assess the dimensions of the pelvis by palpation and measurement of the distance between bony landmarks.
2. Radiological pelvimetry: This uses X-ray or CT imaging to obtain more accurate measurements of the pelvic diameters, including the anteroposterior, transverse, and oblique dimensions.
3. Magnetic resonance imaging (MRI) pelvimetry: This method is considered the most accurate for assessing the size and shape of the pelvis, as it provides detailed images without radiation exposure.

Pelvimetry is often used in obstetrics to evaluate whether a woman's pelvis can accommodate a fetus during childbirth (known as "obstetric pelvimetry"). It helps healthcare providers determine if a vaginal delivery is possible or if a cesarean section may be necessary. However, the use of pelvimetry in modern obstetrics has become less common due to its limited predictive value and the increasing focus on individualized birth management.

Vacuum extraction, obstetrical is a medical procedure used during childbirth to help deliver the baby when there are signs of fetal distress or if the mother is experiencing exhaustion during labor. This assisted delivery technique involves the application of suction through a vacuum device that attaches to the baby's head, allowing the healthcare provider to gently pull the baby out as the mother pushes.

The vacuum extractor consists of a soft or rigid cup connected to a pump, which creates negative pressure inside the cup. The cup is placed on the fetal scalp and engaged during a contraction when the cervix is fully dilated and the baby's head has descended into the pelvis. The healthcare provider then uses controlled traction to help deliver the baby while monitoring both the mother and the infant for any signs of distress or complications.

Vacuum extraction should only be performed by experienced healthcare providers, as it carries risks such as scalp trauma, cephalohematoma (a collection of blood under the skin on the baby's head), subgaleal hematoma (a more serious type of bleeding beneath the scalp), and intracranial hemorrhage (bleeding inside the skull). Proper evaluation, technique, and monitoring are crucial to minimize these risks and ensure a safe delivery for both mother and baby.

Pregnancy is a physiological state or condition where a fertilized egg (zygote) successfully implants and grows in the uterus of a woman, leading to the development of an embryo and finally a fetus. This process typically spans approximately 40 weeks, divided into three trimesters, and culminates in childbirth. Throughout this period, numerous hormonal and physical changes occur to support the growing offspring, including uterine enlargement, breast development, and various maternal adaptations to ensure the fetus's optimal growth and well-being.

Congenital structural myopathies are a group of inherited genetic disorders that affect the structure and function of skeletal muscles. These conditions are present at birth or develop in early infancy and are caused by genetic mutations that lead to abnormalities in the muscle contractile apparatus, including the sarcomere, muscle filaments, and muscle membrane.

The structural abnormalities can affect the muscle fibers' ability to generate force, leading to muscle weakness, hypotonia (low muscle tone), and other symptoms. The severity of the condition can vary widely, from mild to severe, depending on the specific type of myopathy and the extent of muscle involvement.

Examples of congenital structural myopathies include:

1. Congenital fiber-type disproportion (CFTD): a condition characterized by small, atrophic type 1 muscle fibers and normal or enlarged type 2 fibers.
2. Central core disease (CCD): a condition caused by mutations in the ryanodine receptor gene, which leads to the formation of abnormal structures called cores within the muscle fibers.
3. Nemaline myopathy: a condition characterized by the presence of rod-shaped structures called nemalines in the muscle fibers.
4. Myotubular myopathy: a condition caused by mutations in the myotubularin gene, which leads to abnormalities in the muscle fiber nuclei and weakened muscle function.
5. Congenital muscular dystrophy (CMD): a group of conditions characterized by muscle weakness, hypotonia, and joint contractures, often associated with structural abnormalities in the muscle membrane or extracellular matrix.

Diagnosis of congenital structural myopathies typically involves a combination of clinical evaluation, genetic testing, and muscle biopsy. Treatment is generally supportive and may include physical therapy, orthotics, and assistive devices to help manage symptoms and improve function. In some cases, medications or surgical interventions may be necessary to address specific complications.

Muscle hypotonia, also known as decreased muscle tone, refers to a condition where the muscles appear to be flaccid or lacking in tension and stiffness. This results in reduced resistance to passive movements, making the limbs feel "floppy" or "like a rag doll." It can affect any muscle group in the body and can be caused by various medical conditions, including neurological disorders, genetic diseases, and injuries to the nervous system. Hypotonia should not be confused with muscle weakness, which refers to the inability to generate normal muscle strength.

An encyclopedia is a comprehensive reference work containing articles on various topics, usually arranged in alphabetical order. In the context of medicine, a medical encyclopedia is a collection of articles that provide information about a wide range of medical topics, including diseases and conditions, treatments, tests, procedures, and anatomy and physiology. Medical encyclopedias may be published in print or electronic formats and are often used as a starting point for researching medical topics. They can provide reliable and accurate information on medical subjects, making them useful resources for healthcare professionals, students, and patients alike. Some well-known examples of medical encyclopedias include the Merck Manual and the Stedman's Medical Dictionary.

The pelvic bones, also known as the hip bones, are a set of three irregularly shaped bones that connect to form the pelvic girdle in the lower part of the human body. They play a crucial role in supporting the spine and protecting the abdominal and pelvic organs.

The pelvic bones consist of three bones:

1. The ilium: This is the largest and uppermost bone, forming the majority of the hip bone and the broad, flaring part of the pelvis known as the wing of the ilium or the iliac crest, which can be felt on the side of the body.
2. The ischium: This is the lower and back portion of the pelvic bone that forms part of the sitting surface or the "sit bones."
3. The pubis: This is the front part of the pelvic bone, which connects to the other side at the pubic symphysis in the midline of the body.

The pelvic bones are joined together at the acetabulum, a cup-shaped socket that forms the hip joint and articulates with the head of the femur (thigh bone). The pelvic bones also have several openings for the passage of blood vessels, nerves, and reproductive and excretory organs.

The shape and size of the pelvic bones differ between males and females due to their different roles in childbirth and locomotion. Females typically have a wider and shallower pelvis than males to accommodate childbirth, while males usually have a narrower and deeper pelvis that is better suited for weight-bearing and movement.

Prolonged pregnancy, also known as post-term pregnancy, is a medical condition defined as a pregnancy that continues beyond 42 weeks (294 days) of gestation from the first day of the last menstrual period. It is important to note that this definition is based on the estimated date of delivery and not the actual conception date. Prolonged pregnancies are associated with increased risks for both the mother and the fetus, including stillbirth, meconium aspiration, fetal distress, and difficulty during labor and delivery. Therefore, healthcare providers closely monitor pregnant women who reach 41 weeks of gestation to ensure timely delivery if necessary.

A postmature infant is a newborn who is delivered at or after 42 weeks (294 days) of gestation. These infants are also known as "post-term" or "post-dates." At this stage, the placenta may not function optimally, leading to potential issues such as decreased fetal movement, meconium staining of amniotic fluid, and low birth weight. Postmature infants may require close monitoring and evaluation after delivery to ensure their well-being.