# Seminar 9: Cesarean Delivery and Operative Obstetrics ## Year 3: Obstetrics and Gynecology Clerkship --- ## Learning Objectives By the end of this seminar, students will be able to: 1. Identify indications for cesarean delivery 2. Describe cesarean delivery technique 3. Manage trial of labor after cesarean 4. Recognize complications of cesarean delivery 5. Apply principles of vaginal birth after cesarean 6. Describe shoulder dystocia management --- ## Seminar Outline ### I. Cesarean Delivery Indications Cesarean delivery is the most common major surgical procedure performed in the United States, with rates approaching one-third of all deliveries, and understanding the indications and decision-making process is essential for obstetric care. Labor arrest, which includes failure to progress in the first stage (cervical dilation) or second stage (descent), accounts for approximately 35% of primary cesarean deliveries and represents the most common indication. Non-reassuring fetal status, as determined by fetal heart rate monitoring or other indicators of fetal compromise, accounts for approximately 25% of cesarean deliveries and often requires rapid decision-making. Malpresentation, primarily breech presentation, accounts for approximately 15% of cesarean deliveries, while prior cesarean delivery without trial of labor accounts for another 10%, reflecting the trend toward elective repeat cesarean in many settings. Absolute indications for cesarean delivery represent clinical situations where vaginal delivery would pose unacceptable risk to the mother or fetus. Complete placenta previa, where the placenta completely covers the internal cervical os, prevents safe vaginal delivery and constitutes an absolute indication. Umbilical cord prolapse with a viable fetus requires immediate cesarean delivery unless vaginal delivery is imminent, as continued cord compression during prolonged labor would cause fetal demise. Uterine rupture is a surgical emergency requiring immediate laparotomy. Vasa previa, with fetal vessels crossing the membranes over the internal os, carries high risk of fetal exsanguination if membranes rupture. Active primary genital herpes at the time of labor indicates cesarean to prevent neonatal transmission. Maternal HIV infection with viral load exceeding 1000 copies per milliliter warrants cesarean to reduce vertical transmission risk. Relative indications for cesarean delivery represent situations where cesarean may be preferred but vaginal delivery is not absolutely contraindicated. Prior classical cesarean incision (vertical incision in the upper contractile portion of the uterus) carries significantly higher uterine rupture risk during labor than low transverse incision, making repeat cesarean generally preferred. Prior full-thickness myomectomy, particularly involving entry into the endometrial cavity, carries unknown but potentially elevated rupture risk. Breech presentation is considered a relative indication because, while external cephalic version may be attempted and vaginal breech delivery is possible in selected circumstances with experienced providers, cesarean is recommended in most settings based on trial data showing improved neonatal outcomes. Suspected fetal macrosomia exceeding 4500 grams in diabetic patients warrants discussion of cesarean to prevent shoulder dystocia. Certain maternal cardiac conditions may benefit from avoiding the hemodynamic stresses of labor. The distinction between emergent and scheduled cesarean delivery influences preparation, counseling, and operative approach. Emergent cesarean is required for acute, life-threatening conditions including cord prolapse, suspected uterine rupture, placental abruption with significant hemorrhage, and category III fetal heart rate tracings indicating probable fetal acidosis. The urgency of emergent cesarean varies, with some situations requiring delivery within minutes while others allow time for appropriate preparation. Scheduled cesarean deliveries are planned in advance for indications including prior cesarean without desire for trial of labor, known placenta previa, persistent malpresentation, and maternal request. The timing of scheduled cesarean should generally be at or after 39 weeks gestation to minimize neonatal respiratory morbidity, unless earlier delivery is indicated for maternal or fetal reasons. Panel A: Pie chart showing distribution of cesarean indications with labor arrest (35%), non-reassuring fetal status (25%), malpresentation (15%), prior cesarean (10%), and other causes. Panel B: Absolute indications list including placenta previa, cord prolapse, uterine rupture, vasa previa, active herpes, and high viral load HIV. Panel C: Relative indications comparison showing prior classical incision, prior myomectomy, breech, macrosomia with diabetes, and cardiac disease. Panel D: Emergent versus scheduled cesarean classification with timing considerations and clinical examples. --- ### II. Preoperative Considerations Informed consent for cesarean delivery should be obtained whenever possible and should include discussion of the indication, procedure, risks, benefits, and alternatives. The specific indication for cesarean should be clearly explained, including why vaginal delivery is not appropriate or has become inadvisable during labor. Risks discussed should include bleeding potentially requiring transfusion, infection of the wound or uterus, injury to bladder, bowel, or blood vessels, blood clots, risks of anesthesia, and implications for future pregnancies including increased risk of abnormal placentation. Alternatives, when applicable, should be discussed, though in many emergency situations cesarean is the only reasonable option. Anesthesia risks specific to the planned technique should be addressed, ideally by the anesthesiologist. Documentation of the consent process is essential for medical-legal purposes and to ensure patient understanding. Preoperative preparation ensures patient safety and optimal surgical conditions. NPO (nothing by mouth) status of 6-8 hours is preferred for elective cases to reduce aspiration risk, though emergency cesarean may proceed regardless of NPO status with appropriate aspiration precautions. Laboratory evaluation includes complete blood count to assess for anemia and platelet count, and type and screen to have blood available for transfusion if needed. Large-bore intravenous access should be established, typically with at least one 18-gauge or larger IV catheter. Prophylactic antibiotics, typically a first-generation cephalosporin such as cefazolin, should be administered within 60 minutes before skin incision to reduce surgical site infection. Urinary catheter placement before surgery allows continuous bladder drainage during and after the procedure, reducing the risk of bladder injury and facilitating uterine access. Anesthesia for cesarean delivery is most commonly regional, with neuraxial techniques providing excellent anesthesia while allowing the mother to be awake for the delivery. Spinal anesthesia is the most common technique for scheduled cesarean, providing rapid onset of dense anesthesia with a single injection of local anesthetic and opioid into the subarachnoid space. Epidural anesthesia may be used if an epidural catheter is already in place from labor analgesia, with the block extended by administering a larger dose of local anesthetic. Combined spinal-epidural provides the rapid onset of spinal with the flexibility of an epidural catheter for additional dosing if needed. General anesthesia is reserved for true emergencies when there is insufficient time for regional anesthesia, for contraindications to regional techniques such as coagulopathy or patient refusal, or when regional anesthesia fails. Aspiration prophylaxis with nonparticulate antacid should be administered regardless of anesthesia type. Patient positioning for cesarean delivery optimizes surgical access while minimizing maternal physiologic compromise. The patient is positioned supine on the operating table with left lateral tilt of 15-30 degrees to displace the gravid uterus off the inferior vena cava and prevent supine hypotensive syndrome. This tilt can be achieved using a wedge under the right hip or by tilting the entire operating table. Arms may be extended on arm boards or tucked at the sides depending on the patient's comfort, surgical team preference, and body habitus. Pressure points should be padded to prevent nerve injury, particularly the ulnar nerve at the elbow and the peroneal nerve at the fibular head. Adequate exposure of the lower abdomen while maintaining patient dignity and warmth is achieved through appropriate draping. Panel A: Informed consent checklist showing indication discussion, risks (bleeding, infection, injury, clots), alternatives, and documentation requirements. Panel B: Preoperative preparation timeline showing NPO status, labs, IV access, antibiotic timing, and catheter placement. Panel C: Anesthesia options comparison showing spinal, epidural, combined spinal-epidural, and general anesthesia with indications for each. Panel D: Patient positioning illustration showing left lateral tilt, pressure point padding, and arm positioning options. --- ### III. Surgical Technique Skin incision options for cesarean delivery include transverse and vertical approaches, each with specific advantages. The Pfannenstiel incision is the most commonly used, a curvilinear transverse incision made approximately 2-3 centimeters above the symphysis pubis, typically within or at the superior border of the pubic hairline. This incision provides excellent cosmesis and reduced postoperative pain but may provide limited exposure in emergencies or with significant adhesive disease. The Joel-Cohen incision is a straight transverse incision made slightly higher than the Pfannenstiel and may be associated with faster entry and reduced blood loss. Vertical midline incision provides maximum exposure and is the fastest approach for emergencies or when extensive pathology is anticipated, though it has inferior cosmesis and higher wound complication rates. The choice of skin incision does not dictate the type of uterine incision, and a low transverse uterine incision can be performed through a vertical skin incision. The uterine incision type has significant implications for the current delivery and future pregnancies. The low transverse incision is performed in the lower uterine segment, which is relatively thin and avascular, and is the standard approach used in the majority of cesarean deliveries. This incision type is associated with the lowest risk of uterine rupture in subsequent pregnancies, allowing for consideration of trial of labor after cesarean. The classical incision is a vertical incision in the upper contractile portion of the uterus and is rarely performed today, indicated primarily when the lower segment is not well developed (very early preterm cesarean), with placenta accreta covering the lower segment, or when lower segment access is impossible. A low vertical incision can be made in the lower segment but carries intermediate rupture risk. A J or T extension of a low transverse incision may become necessary when the initial incision proves inadequate for delivery, and this carries increased rupture risk in subsequent pregnancies. The surgical steps of cesarean delivery follow a systematic approach that ensures safe delivery and minimizes complications. After skin incision, dissection proceeds through subcutaneous tissue to the rectus fascia, which is incised transversely. The rectus muscles are separated in the midline, and the peritoneum is entered. A bladder flap is created by incising the visceral peritoneum overlying the lower uterine segment and reflecting the bladder inferiorly, though some surgeons omit this step. The hysterotomy (uterine incision) is made in the lower segment, with care to avoid injury to the fetus. The fetal head is delivered through the incision with gentle upward pressure, followed by the body. After delivery of the neonate and clamping of the cord, the placenta is delivered, either spontaneously or manually. Uterine closure, hemostasis, and abdominal closure complete the procedure. Delivery of the fetus requires technique adapted to the fetal presentation and station. For vertex presentation, the surgeon's hand is inserted beneath the fetal head, which is flexed and elevated through the uterine incision while an assistant may provide gentle fundal pressure. If the head is deeply engaged in the pelvis, a hand or foot can be used to elevate it from below vaginally. For breech presentation, the surgeon identifies and grasps the fetal feet or hips and delivers the fetus by gentle traction with progressive delivery of the legs, trunk, arms, and head. Transverse lie may require internal podalic version to bring the feet to the incision, or extension of the incision if the back is down. An impacted fetal head that is difficult to elevate from the pelvis can be managed by having an assistant push the head up through the vagina. Excessive force should be avoided to prevent uterine extensions and fetal injury. Panel A: Skin incision comparison showing Pfannenstiel (curvilinear low transverse), Joel-Cohen (straight transverse), and vertical midline with advantages and disadvantages. Panel B: Uterine incision types showing low transverse, classical, low vertical, and T-extension with indications and rupture risk for each. Panel C: Surgical step sequence from skin incision through fascial entry, peritoneal entry, bladder flap, hysterotomy, delivery, placenta, and closure. Panel D: Delivery techniques by presentation showing vertex (head elevation), breech (feet or hips), and transverse (version or extension) approaches. --- ### IV. Vaginal Birth After Cesarean (VBAC) The terminology surrounding delivery after prior cesarean delivery requires clarity for appropriate counseling and decision-making. Trial of labor after cesarean (TOLAC) refers to the planned attempt at vaginal delivery in a woman with prior cesarean, recognizing that not all trials of labor will result in vaginal delivery. Vaginal birth after cesarean (VBAC) refers to successful vaginal delivery following a trial of labor after cesarean. Elective repeat cesarean delivery (ERCD) refers to scheduled cesarean without labor in a woman with prior cesarean. The decision between TOLAC and ERCD involves weighing the potential benefits of successful VBAC against the risks of failed TOLAC and uterine rupture, and this decision should be made collaboratively between the patient and provider. Success rates for TOLAC vary based on maternal and pregnancy characteristics, with overall success rates of 60-80% when appropriate candidates are selected. The strongest predictor of successful VBAC is prior vaginal delivery, particularly prior successful VBAC, which is associated with success rates of 85-90%. Women without prior vaginal delivery have lower success rates of 60-70%, and those whose prior cesarean was performed for a recurring indication such as cephalopelvic disproportion or failure to progress have even lower rates. Spontaneous onset of labor is associated with higher success rates than induced labor. Favorable cervical examination at admission predicts higher success. Maternal obesity, advanced maternal age, fetal macrosomia, and short interpregnancy interval are associated with lower success rates. Prediction calculators incorporating multiple factors can help individualize counseling. Good candidates for TOLAC have characteristics associated with high success rates and low rupture risk. Prior low transverse cesarean incision is the standard requirement, as this incision type is associated with the lowest rupture risk of 0.5-1%. Prior successful VBAC strongly predicts subsequent success and indicates that the pelvis is adequate for vaginal delivery. A non-recurring indication for the prior cesarean, such as breech presentation or non-reassuring fetal heart tracing, suggests that the circumstances preventing vaginal delivery previously may not recur. Singleton pregnancy in vertex presentation at term represents the population in which TOLAC has been most studied. Spontaneous labor onset is associated with both higher success rates and lower rupture risk compared to induction. Poor candidates for TOLAC have characteristics associated with high rupture risk or low success likelihood, and elective repeat cesarean may be more appropriate. Prior classical uterine incision carries uterine rupture risk of 4-9%, and trial of labor is generally contraindicated. Multiple prior cesarean deliveries (two or more) increase rupture risk with each additional cesarean, though TOLAC may still be offered after counseling. Prior uterine rupture is a contraindication to TOLAC due to high recurrence risk. Unknown prior incision type presents a challenge; if the prior cesarean was performed at term for standard indications, low transverse incision is likely, but documentation should be sought when possible. Short interpregnancy interval of less than 18 months from prior cesarean to conception is associated with increased rupture risk. Medical or obstetric conditions requiring scheduled delivery may make TOLAC impractical. Panel A: Terminology definitions distinguishing TOLAC (planned attempt), VBAC (successful vaginal delivery), and ERCD (scheduled repeat cesarean). Panel B: Success rate chart showing overall 60-80% success, 85-90% with prior vaginal delivery, and factors affecting success including prior VBAC, spontaneous labor, and cervical status. Panel C: Good candidate criteria including prior low transverse, prior successful VBAC, non-recurring indication, singleton vertex, and spontaneous labor. Panel D: Poor candidate factors including prior classical incision, multiple cesareans, prior rupture, unknown incision, and short interpregnancy interval. --- ### V. TOLAC Management Counseling for TOLAC should be thorough, individualized, and documented, covering both the potential benefits of successful VBAC and the risks of failed TOLAC and uterine rupture. Success rate estimation should incorporate individual factors rather than simply quoting overall statistics. The risk of uterine rupture with prior low transverse incision is 0.5-1%, and this risk should be contextualized by explaining what rupture means (separation of the uterine scar) and potential consequences (fetal death, hysterectomy, maternal death, though the latter is rare). Benefits of successful VBAC include shorter recovery, avoidance of major surgery, lower infection risk, and preservation of the option for multiple future vaginal deliveries. Risks of failed TOLAC include emergency cesarean with its associated risks, which may be higher than planned repeat cesarean, particularly if rupture occurs. Documentation of this counseling and the patient's informed decision is essential. Institutional and provider requirements for safe TOLAC must be met to offer this option. The hospital must have the capability to perform emergency cesarean delivery when needed, including available operating room, surgical instruments, and support staff. A surgeon (obstetrician) must be immediately available to perform emergency cesarean, meaning physically present in the hospital, not simply on call from home. Anesthesia personnel capable of providing emergency anesthesia must also be immediately available. Blood products must be available, and patients should have a type and screen on admission. These requirements recognize that uterine rupture requires delivery within minutes to prevent permanent fetal injury, and delays in assembling a surgical team may result in adverse outcomes. Institutions without these capabilities should not offer TOLAC. Labor management during TOLAC involves specific considerations while following standard labor management principles. Cervical ripening with prostaglandins (misoprostol, dinoprostone) is contraindicated due to significantly increased rupture risk. Oxytocin for induction or augmentation can be used but is associated with modestly increased rupture risk, and lower starting doses with careful titration are prudent. Mechanical methods such as Foley catheter for cervical ripening have not been shown to increase rupture risk and may be used. Epidural analgesia is acceptable and does not mask the signs of uterine rupture as once feared. Continuous electronic fetal monitoring is recommended throughout labor to detect fetal heart rate changes that may indicate rupture. The threshold for proceeding to cesarean should be lower than in unscarred patients if concerning signs develop. Recognition of uterine rupture is critical, as rapid diagnosis and delivery are essential to prevent fetal death and maternal morbidity. Fetal heart rate abnormalities are the most common and often the earliest sign, with prolonged deceleration or bradycardia being particularly concerning. Loss of station, where the presenting part recedes away from the birth canal, suggests that the fetus is being extruded through the uterine rupture site. Sudden severe abdominal pain, even in the presence of epidural analgesia, may indicate rupture. Vaginal bleeding may occur but is often minimal or absent. Change in contraction pattern, including cessation of previously regular contractions, may occur. Maternal hemodynamic instability with tachycardia and hypotension suggests significant intra-abdominal hemorrhage. If rupture is suspected, immediate cesarean delivery should be performed without waiting for confirmatory testing. Panel A: Counseling framework showing individualized success estimation, rupture risk explanation (0.5-1% with low transverse), benefits of VBAC, and risks of failed TOLAC. Panel B: Institutional requirements checklist showing emergency cesarean capability, immediately available surgeon and anesthesia, and blood availability. Panel C: Labor management showing prostaglandin contraindication, cautious oxytocin use, acceptable mechanical ripening and epidural, and continuous monitoring. Panel D: Uterine rupture recognition showing fetal heart rate abnormalities, loss of station, sudden pain, vaginal bleeding, contraction changes, and maternal instability. --- ### VI. Cesarean Complications Intraoperative complications during cesarean delivery require prompt recognition and management to prevent serious maternal morbidity. Hemorrhage is the most common significant complication, with causes including uterine atony (failure of the uterus to contract after delivery), placenta accreta spectrum, uterine incision extensions, and coagulopathy. Management includes uterotonic medications (oxytocin, methylergonovine, carboprost, misoprostol), uterine massage, uterine compression sutures, vessel ligation, and when conservative measures fail, hysterectomy. Bladder injury occurs in approximately 0.3% of primary cesarean deliveries but increases with repeat cesarean due to adhesions; injury should be identified and repaired intraoperatively with consultation as needed. Bowel injury is rare but may occur particularly with adhesive disease; recognition and appropriate repair or consultation are essential. Ureteral injury is uncommon but may occur with lateral extension of the uterine incision or during attempts to control bleeding; urology consultation should be obtained. Postoperative complications in the days to weeks following cesarean delivery encompass infectious, thromboembolic, and wound complications. Wound infection manifests as erythema, induration, warmth, or drainage at the incision site, typically presenting 4-7 days postoperatively; treatment includes antibiotics and opening the wound if collection is present. Endometritis (infection of the uterine lining and myometrium) presents with fever, uterine tenderness, and foul-smelling lochia, typically within the first few days postoperatively; treatment is intravenous broad-spectrum antibiotics. Ileus with delayed return of bowel function manifests as abdominal distension, nausea, and inability to tolerate oral intake; management is supportive with bowel rest and nasogastric decompression if severe. Venous thromboembolism (DVT and pulmonary embolism) represents a leading cause of maternal death; prevention includes early ambulation and pharmacologic prophylaxis for high-risk patients. Long-term complications of cesarean delivery affect future pregnancies and may manifest years later. Adhesion formation occurs after cesarean delivery and increases with each subsequent cesarean, potentially complicating future abdominal surgery and increasing operative time and complication risk with repeat cesarean. Placenta accreta spectrum (accreta, increta, percreta) occurs when the placenta implants abnormally into or through the myometrium, and risk increases dramatically with prior cesarean, particularly when combined with placenta previa. Uterine rupture risk in subsequent pregnancy depends on incision type, with low transverse carrying 0.5-1% risk and classical incision carrying 4-9% risk. Cesarean scar pregnancy, implantation of a subsequent pregnancy in the cesarean scar, is rare but increasing and can lead to severe hemorrhage. These risks should be discussed with patients considering cesarean delivery, particularly elective cesarean without medical indication. Prevention strategies for cesarean complications begin before surgery and continue through the postoperative period. Prophylactic antibiotics administered within 60 minutes before incision reduce surgical site infection by approximately 50%. Thromboprophylaxis with sequential compression devices during surgery and early postoperative ambulation reduce VTE risk; pharmacologic prophylaxis with low-molecular-weight heparin is indicated for high-risk patients. Meticulous surgical technique with attention to hemostasis reduces bleeding complications. Careful identification of anatomy, particularly the bladder, reduces injury risk. Appropriate closure technique, including adequate approximation of the uterine incision without excessive tension, promotes healing. Enhanced recovery after cesarean (ERAC) protocols that include early oral intake, early ambulation, multimodal analgesia, and early catheter removal improve recovery and reduce complications. Panel A: Intraoperative complications showing hemorrhage (atony, accreta, extensions), bladder injury, bowel injury, and ureteral injury with management approaches. Panel B: Postoperative complications timeline showing wound infection (4-7 days), endometritis (first days), ileus, and VTE with presentations and treatments. Panel C: Long-term complications showing adhesion progression, placenta accreta spectrum risk increase, uterine rupture risk by incision type, and cesarean scar pregnancy. Panel D: Prevention strategies showing antibiotic timing, thromboprophylaxis methods, surgical technique principles, and ERAC protocol components. --- ### VII. Shoulder Dystocia Shoulder dystocia is an obstetric emergency defined as impaction of the fetal shoulders after delivery of the head, requiring additional maneuvers beyond gentle downward traction on the head to effect delivery of the body. This complication occurs when the anterior fetal shoulder becomes impacted behind the maternal pubic symphysis, preventing further descent despite normal traction on the head. The incidence is approximately 0.5-1% of vaginal deliveries overall but increases significantly with macrosomia and diabetes. Shoulder dystocia is unpredictable in the majority of cases, occurring without identifiable risk factors, which limits the effectiveness of prediction and prevention strategies. When it occurs, prompt recognition and systematic management are essential to minimize maternal and fetal complications. Risk factors for shoulder dystocia, while often present, are neither sensitive nor specific enough to predict individual cases reliably. Fetal macrosomia (birth weight greater than 4000 grams) is associated with increased shoulder dystocia risk, with risk rising progressively with increasing weight. Maternal diabetes, particularly with poor glycemic control leading to asymmetric fetal growth with disproportionately large shoulders, increases risk beyond what would be predicted by birth weight alone. Maternal obesity increases risk through association with macrosomia and potential mechanical factors. Prolonged second stage of labor suggests difficulty with descent that may continue during shoulder delivery. Operative vaginal delivery (vacuum or forceps) is associated with increased shoulder dystocia, possibly due to selection of cases with difficult descent. Prior shoulder dystocia carries recurrence risk of 10-15%, prompting consideration of cesarean delivery for subsequent pregnancies, particularly with estimated fetal weight equal to or exceeding the prior affected delivery. Recognition of shoulder dystocia must be immediate to initiate appropriate management. The "turtle sign" describes the appearance of the fetal head against the perineum, where the head is delivered but then retracts tightly against the perineum as if the turtle is pulling its head back into its shell. Failure of external rotation (restitution) of the head to align with the shoulders suggests impaction. Difficulty delivering the shoulders with normal gentle downward traction on the head indicates true dystocia rather than simply a tight fit. Awareness of risk factors heightens vigilance, but the unpredictable nature of many cases means that all delivery attendants must be prepared to recognize and manage this complication. Complications of shoulder dystocia can be severe for both the neonate and mother, underscoring the importance of skilled management. Brachial plexus injury occurs in 10-20% of shoulder dystocia cases, ranging from temporary palsy (most common) to permanent Erb's or Klumpke's palsy. Clavicle or humerus fracture may occur, either spontaneously from the impaction or during delivery maneuvers; these generally heal without long-term sequelae. Hypoxic-ischemic brain injury can occur if delivery is significantly delayed, as the umbilical cord is often compressed between the fetal body and the pelvis after head delivery. Fetal death, while rare, may occur with prolonged or unresolved dystocia. Maternal complications include postpartum hemorrhage from uterine atony or lacerations, severe perineal lacerations including third- and fourth-degree tears, and psychological trauma from a frightening delivery experience. Panel A: Shoulder dystocia definition illustration showing anterior shoulder impacted behind symphysis with head delivered but body impeded. Panel B: Risk factor assessment showing macrosomia, diabetes, obesity, prolonged second stage, operative delivery, and prior dystocia with associated risk increases. Panel C: Recognition signs showing turtle sign (head retraction), failure of restitution, and difficulty with normal traction. Panel D: Complication overview showing neonatal complications (brachial plexus injury, fractures, hypoxic injury, death) and maternal complications (hemorrhage, lacerations, trauma). --- ### VIII. Shoulder Dystocia Management Initial management of shoulder dystocia focuses on calling for help and applying the most effective low-risk maneuvers. Calling for help should be immediate, summoning additional nurses, obstetricians, anesthesiologists, and neonatologists; one team member should note the time to track duration. The McRoberts maneuver is performed first, involving sharp flexion of the maternal thighs onto the abdomen by the assistants; this flattens the sacrum and rotates the pubic symphysis cephalad, increasing the anteroposterior diameter of the pelvis and often releasing the impacted shoulder. Suprapubic pressure is applied simultaneously by an assistant, with the heel of the hand pressing downward and laterally just above the pubic symphysis to push the anterior fetal shoulder away from the symphysis and into the oblique diameter. Fundal pressure must never be applied as it worsens impaction and increases injury risk. Episiotomy should be considered to allow room for internal maneuvers, though it does not directly relieve bony impaction. The HELPERR mnemonic provides a systematic approach to shoulder dystocia management when initial maneuvers are unsuccessful. H stands for Help, reminding providers to call for assistance immediately. E stands for Evaluate for episiotomy, considering whether additional room is needed for maneuvers. L stands for Legs, referring to the McRoberts maneuver. P stands for Pressure, referring to suprapubic pressure. E stands for Enter, meaning entry into the vagina to perform rotational maneuvers. R stands for Remove the posterior arm. The final R stands for Roll the patient to hands and knees position (Gaskin maneuver). This systematic approach ensures that providers progress through maneuvers without skipping options. Rotational maneuvers are internal maneuvers that aim to dislodge the impacted shoulder by rotating the fetus to a more favorable diameter. The Rubin maneuver involves inserting a hand behind the posterior aspect of the anterior shoulder and pushing it anteriorly (toward the fetal face), which adducts the shoulders and reduces the bisacromial diameter. The Woods screw maneuver involves placing fingers on the anterior aspect of the posterior shoulder and rotating the fetus 180 degrees (like turning a screw), moving the posterior shoulder to the anterior position and vice versa. The reverse Woods screw involves rotating in the opposite direction. These maneuvers attempt to move the anterior shoulder from its position behind the symphysis into the larger oblique or transverse pelvic diameter, allowing delivery to proceed. Additional maneuvers are employed when standard approaches fail, recognizing that persistent dystocia carries high risk of fetal harm. Delivery of the posterior arm involves inserting a hand into the vagina, locating the posterior fetal arm, flexing the elbow, and sweeping the arm across the fetal chest and out of the vagina; this reduces the diameter that must traverse the pelvis and often allows the anterior shoulder to dislodge. The Gaskin maneuver (all-fours position) involves repositioning the mother onto her hands and knees, which changes the pelvic dimensions and may dislodge the shoulder; this requires the mother to be able to reposition quickly and may be difficult with epidural anesthesia. The Zavanelli maneuver (cephalic replacement) involves flexing the fetal head, pushing it back into the vagina, and performing cesarean delivery; this is a last resort with significant risk. Deliberate fracture of the fetal clavicle is sometimes discussed as an option of last resort, though it is technically difficult and rarely performed. Panel A: Initial maneuvers showing call for help, McRoberts position (thigh hyperflexion), suprapubic pressure technique, and episiotomy consideration. Panel B: HELPERR mnemonic breakdown with Help, Evaluate episiotomy, Legs (McRoberts), Pressure (suprapubic), Enter (rotational), Remove arm, Roll (Gaskin). Panel C: Rotational maneuver illustrations showing Rubin (push posterior shoulder anterior), Woods screw (180-degree rotation), and reverse Woods. Panel D: Additional maneuvers showing posterior arm delivery technique, Gaskin positioning, and Zavanelli as last resort. --- ### IX. Breech Presentation Breech presentation, where the fetal buttocks or lower extremities present first rather than the head, occurs in 3-4% of term pregnancies and has specific management considerations. Frank breech, the most common type, involves flexion at the hips with extended knees so that the fetal feet are near the head, creating a pike position. Complete breech involves flexion at both hips and knees, with the fetus in a sitting position. Incomplete or footling breech involves one or both hips not fully flexed, allowing one or both feet to present below the buttocks. The type of breech affects management decisions, with frank and complete breech generally considered more favorable for vaginal delivery if attempted, while footling breech carries higher risk of cord prolapse. Management options for breech presentation include external cephalic version, planned cesarean delivery, and in select circumstances, vaginal breech delivery. External cephalic version (ECV) is the preferred initial approach for breech presentation at term, as successful version allows for normal cephalic vaginal delivery. Planned cesarean delivery is recommended when ECV is unsuccessful, declined, or contraindicated, based on evidence from the Term Breech Trial showing lower perinatal mortality and morbidity with planned cesarean compared to planned vaginal breech delivery. Vaginal breech delivery may be offered in selected cases by experienced providers at institutions with appropriate resources, though this expertise has become increasingly rare as cesarean has become the standard of care. External cephalic version is a procedure to manually rotate the fetus from breech to cephalic presentation through the maternal abdomen. Optimal timing is at 37 weeks gestation, allowing spontaneous version before this time while avoiding version after labor onset. Success rates average approximately 60% but vary based on factors including parity (higher success in multiparous women), amniotic fluid volume (more fluid facilitates version), and fetal back position (anterior back more difficult). The technique involves identifying fetal position by ultrasound, administering tocolytic if desired (may improve success), and applying gradual pressure to the fetal buttocks and head to encourage forward or backward somersault. Nonstress test should be performed before and after the attempt to document fetal well-being. Complications are rare but include placental abruption, premature rupture of membranes, and fetal heart rate abnormalities necessitating emergency cesarean. RhoGAM should be administered to Rh-negative women. Vaginal breech delivery, when performed, carries specific risks that must be weighed against cesarean delivery risks. Cord prolapse risk is elevated because the presenting part does not fully occlude the cervix, particularly with incomplete breech. After-coming head entrapment is the most feared complication, occurring when the body delivers through an incompletely dilated cervix but the larger head cannot follow; this can cause severe fetal hypoxia and injury. Nuchal arms (arms trapped behind the head) complicate delivery. The Term Breech Trial demonstrated significantly higher perinatal mortality and serious neonatal morbidity with planned vaginal breech delivery compared to planned cesarean delivery, shifting practice toward routine cesarean for breech presentation. Providers who offer vaginal breech delivery must have specific training and experience, appropriate patient selection criteria, and willingness to proceed to cesarean if complications arise. Panel A: Breech types illustration showing frank breech (hips flexed, knees extended), complete breech (sitting position), and footling breech (foot presenting). Panel B: Management options comparison showing ECV as first-line, cesarean as standard for failed ECV, and vaginal delivery as select option. Panel C: External cephalic version technique showing 37-week timing, success rate factors, procedure steps, and monitoring requirements. Panel D: Vaginal breech delivery risks showing cord prolapse, after-coming head entrapment, nuchal arms, and Term Breech Trial findings. --- ### X. Other Operative Procedures Cervical cerclage is a procedure to reinforce the cervix in women at risk for cervical insufficiency leading to preterm birth. History-indicated (prophylactic) cerclage is placed at 12-14 weeks in women with a history of cervical insufficiency, defined as painless cervical dilation leading to second-trimester pregnancy loss. Ultrasound-indicated cerclage is placed when short cervix (typically less than 25 mm before 24 weeks) is identified on ultrasound in a woman with prior spontaneous preterm birth, as this combination predicts high preterm birth risk. Rescue (emergency) cerclage is placed when the cervix is found to be dilated without contractions, and while success rates are lower than prophylactic cerclage, it may prolong pregnancy significantly in some cases. Techniques include the McDonald cerclage (simple pursestring suture) and the Shirodkar cerclage (suture placed at the level of the internal os after bladder reflection). Cerclage is removed at 36-37 weeks or earlier if labor occurs or complications arise. Peripartum hysterectomy, surgical removal of the uterus at the time of or shortly after delivery, is performed when conservative measures fail to control life-threatening hemorrhage or when indicated by pathology. Placenta accreta spectrum is the most common indication in modern practice, occurring when the placenta abnormally adheres to or invades the myometrium, preventing normal separation after delivery and causing massive hemorrhage. Uterine atony refractory to uterotonics and other conservative measures may ultimately require hysterectomy when bleeding cannot be controlled. Uterine rupture with extensive damage that cannot be safely repaired may necessitate hysterectomy. Extension of uterine incision that cannot be adequately repaired, particularly with involvement of major vessels, may require hysterectomy. Peripartum hysterectomy is associated with significant morbidity including blood loss, transfusion requirements, and injury to adjacent organs; multidisciplinary planning is indicated for cases where the need is anticipated. Postpartum tubal ligation provides permanent sterilization and is often performed during the cesarean delivery hospitalization. At cesarean delivery, tubal ligation is performed through the existing abdominal incision after uterine closure, typically using the modified Pomeroy technique (ligation and excision of a segment of tube) or Parkland technique (ligation of two separate points with excision of intervening segment). For vaginal delivery, postpartum tubal ligation is performed through a small infraumbilical incision within 48 hours of delivery while the fundus is still near the umbilicus, facilitating access to the tubes. Bilateral salpingectomy (removal of the entire tubes) is increasingly performed instead of partial salpingectomy due to evidence suggesting reduced lifetime ovarian cancer risk. Counseling should emphasize the permanent nature of sterilization and the availability of equally effective but reversible LARC alternatives. Postpartum curettage may be necessary for retained placenta or products of conception contributing to hemorrhage. When the placenta does not separate spontaneously or cannot be completely removed manually, retained placental tissue may cause ongoing bleeding by preventing adequate uterine contraction. Gentle sharp curettage of the uterine cavity can remove retained tissue, though the postpartum uterus is soft and easily perforated, requiring careful technique. Ultrasound guidance may be helpful to identify and target retained tissue. Hysteroscopic evaluation and removal may be appropriate in some cases. The risk of Asherman syndrome (intrauterine adhesions) exists following postpartum curettage, though it is relatively low with a single procedure. Panel A: Cervical cerclage types showing history-indicated (12-14 weeks for cervical insufficiency), ultrasound-indicated (short cervix plus prior PTB), and rescue (dilated cervix without labor) with McDonald and Shirodkar techniques. Panel B: Peripartum hysterectomy indications showing placenta accreta spectrum, refractory atony, uterine rupture, and unrepairable extensions with morbidity considerations. Panel C: Postpartum tubal ligation approaches showing at cesarean (modified Pomeroy, Parkland) and postpartum vaginal delivery (infraumbilical minilaparotomy) with salpingectomy option. Panel D: Postpartum curettage showing indications, technique with perforation risk, ultrasound guidance, and Asherman syndrome risk. --- ## Summary - Cesarean delivery indications include labor arrest (35%), non-reassuring fetal status (25%), malpresentation (15%), and prior cesarean (10%) - Uterine incision types: low transverse (most common, lowest rupture risk), classical (vertical in upper segment, 4-9% rupture risk), J or T extension (intermediate risk) - VBAC success rates are 60-80% overall, with prior vaginal delivery predicting 85-90% success - TOLAC requirements include capability for emergency cesarean, immediately available surgeon and anesthesia, and continuous fetal monitoring - Uterine rupture risk with prior low transverse cesarean is 0.5-1%; signs include prolonged deceleration, loss of station, and sudden pain - Prostaglandins are contraindicated for cervical ripening with prior cesarean; oxytocin may be used cautiously - Shoulder dystocia occurs in 0.5-1% of deliveries; initial response is call for help, McRoberts maneuver, and suprapubic pressure - HELPERR mnemonic: Help, Episiotomy evaluation, Legs (McRoberts), Pressure (suprapubic), Enter (rotational maneuvers), Remove posterior arm, Roll (Gaskin) - External cephalic version for breech at 37 weeks has approximately 60% success rate - Cesarean complications include hemorrhage, infection, VTE, bladder injury, and long-term risks including adhesions and placenta accreta spectrum --- ## Key Terms | Term | Definition | |------|------------| | TOLAC | Trial of labor after cesarean - planned attempt at vaginal delivery in a woman with prior cesarean | | VBAC | Vaginal birth after cesarean - successful vaginal delivery following trial of labor | | Classical incision | Vertical uterine incision in the upper contractile segment, associated with higher rupture risk | | Uterine rupture | Separation of the uterine scar, potentially allowing fetal extrusion and causing hemorrhage | | McRoberts maneuver | Hyperflexion of maternal thighs onto abdomen to increase pelvic diameter during shoulder dystocia | | Suprapubic pressure | Downward and lateral pressure above symphysis to dislodge impacted anterior shoulder | | External cephalic version | Manual rotation of breech fetus to cephalic presentation through the maternal abdomen | | Placenta accreta spectrum | Abnormal placental adherence to or invasion of the myometrium, increasing with prior cesareans | --- *This content is subject to the [MIT License](https://opensource.org/licenses/MIT). © 2024–2026 Hibbert School of Medicine.*