Introduction: Cephalopelvic Disproportion (CPD) is a condition where the baby’s head or body is too large to fit through the mother’s pelvis. This can happen when the baby is too big, the pelvis is too small, the baby is in a wrong position, or the relationship between the baby and the pelvis is incorrect .CPD is rare, but often diagnosed when a women’s labor fails to progress, the cervix has stopped dilating, or the baby does not descend through the pelvis. When an accurate diagnosis of CPD has been made, the safest type of delivery for mother and baby is a cesarean.Possible causes of cephalopelvic disproportion (CPD) include:Large baby due to:Hereditary factors-Diabetes-Postmaturity (still pregnant after the due date has passed)-Multiparity (not the first pregnancy)-Abnormal fetal positions-Small pelvis-Abnormally shaped pelvis.Complications of CPD include an increased risk of cesarean section and shoulder dystocia with a vaginal delivery as well as an increased risk of postpartum bleeding.Most women with CPD have a successful pregnancy outcome after a cesarean delivery and there is no evidence to suggest that CPD affects a baby after its birth. Statistics suggest that about one out of 3 cesarean sections are the result of some form of CPD. Another study shows that 65 percent of women who received a diagnosis of cephalopelvic disproportion in an earlier pregnancy went on to deliver vaginally in subsequent pregnancies. In fact, many of these women had larger babies on subsequent pregnancies than with the CPD baby.
Methods: There are four main types of pelvic shapes in women, each with unique characteristics that can influence childbirth:1-Gynecoid Pelvis: This is the most common type, accounting for about 50%of women. It has a round and wide shape, which is ideal for childbirth, making vaginal delivery easier.2-Android Pelvis: Resembling a male pelvis, this type is heart-shaped or triangular and narrower. It can make vaginal delivery more challenging, often requiring a cesarean section.3-Anthropoid Pelvis: This pelvis is long and oval-shaped, providing more room front to back. While it can facilitate vaginal birth, it may lead to longer labor.4-Platypelloid Pelvis: The least common type, it is wide and flat. This shape can make vaginal delivery more difficult.
Results: Pelvimetry is the measurement of the female pelvis, primarily to assess its size and shape in relation to childbirth. This can help determine if the pelvis is adequate for a vaginal delivery or if there might be complications such as cephalopelvic disproportion, where the baby's head is too large to pass through the pelvis.There are different methods of pelvimetry:1-Clinical Pelvimetry: This involves a physical examination where the healthcare provider manually assesses the dimensions and shape of the pelvis.2-Radiographic Pelvimetry: This uses imaging techniques like X-rays, CT scans, or MRI to measure the pelvis more precisely.However, the routine use of pelvimetry has decreased because many studies suggest that it doesn't significantly change the management of labor and delivery.The choice of pelvimetry method often depends on the clinical situation:1-Suspected Cephalopelvic Disproportion (CPD).2-Previous Obstetric History.3- Fetal Position and Size.4- Maternal Health Conditions.
Conclusion: Clinical pelvimetry steps typically involved:1-Preparation:The healthcare provider explains the procedure to the patient and obtains her consent. The patient is then positioned comfortably, usually lying on her back with her knees bent and feet apart.2- Assessment of Pelvic Inlet: - Diagonal Conjugate: The provider measures the distance from the lower border of the pubic symphysis to the sacral promontory using their fingers.Obstetric Conjugate:This is estimated by subtracting 1.5 to 2 cm from the diagonal conjugate.3- Assessment of Midpelvis:Ischial Spines: The provider palpates the ischial spines to determine their prominence and the distance between them. This helps assess the transverse diameter of the midpelvis.4- Assessment of Pelvic Outlet: Subpubic Angle: The angle formed by the pubic bones is assessed. A wider angle is generally more favorable for vaginal delivery.Intertuberous Diameter: The distance between the ischial tuberosities is measured, which indicates the width of the pelvic outlet.5- Overall Pelvic Shape: The provider evaluates the overall shape of the pelvis (gynecoid, android, anthropoid, or platypelloid) based on the findings from the above assessments.Clinical pelvimetry is a useful tool, but its routine use has declined due to the availability of more precise imaging techniques and the understanding that many women can have a successful vaginal delivery regardless of pelvimetry results.