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VAGINAL DELIVERY Objectives OF TWINS 1. To argue in favor of vaginal delivery of twins. Edward R. Yeomans, M.D. 2. To present the prerequisites for accomplishing objective #1. Texas Tech University Health 3. To review several unique complications Sciences Center of twins and discuss their impact on December 2010 route of delivery. Twins Twins Overview • Fascinating subject • Epidemiology • Fixed names • Biology • Taiuro -- “he who has the first taste of the world” • Kainde -- “he who lags behind” • Ultrasound • Romulus/Remus • Maternal/Perinatal Outcome • Castor/Pollux • Labor and Delivery • Unique complications 1 Twins Twins Epidemiology Biology Incidence 3.2% DZ = 2 eggs, Dichorionic Diamniotic 50% spontaneous, 50% ART MZ = 1 egg and a later division: DZ to MZ = 2-3 to 1 2- MZ = 1/250 0- Day 0-3 Dichorionic Diamniotic MC/MA = 1% of MZ 4- Day 4-8 Monochorionic Diamniotic PNM = 4x singleton > Day 8 Monochorionic Monoamniotic Hellin’s Law (for higher order) > Day 13 Conjoined 2 Twins DZ Factors • Age (up to 37) 5- • Parity (up to 5-6) • Race (B>C>A) • Maternal Family History • Gonadotropins/ART 3 Twins Twins Ultrasound Maternal Complications • Diagnosis • Hypertension • Chorionicity – 20% Monochorionic • Hemorrhage • Anomaly detection • Hydramnios • Guide invasive procedures • Hyperemesis • Fetal growth • Protracted labor • Confirm presentation • Frequent cesarean delivery • ? Assist in delivery Twins Twins Perinatal Complications BEWARE! • Low birth weight Undiagnosed twins – an LBJ phenomenon! Growth restriction • Be alert in triage – abdominal exam Prematurity P t it • Careful ultrasound • Increased perinatal mortality • Danger – one twin completely unmonitored 2% of births, 10% of deaths during labor • Increased abortion – vanishing twin • Delivery may occur in an unfavorable setting • Increased rate of malformations (MZ > DZ) 4 Twins Vaginal Delivery of Twins Labor Specific Issues • Often protracted • Influence of presentation • Confirm presentation • Extremes of birth weight • Estimate weight • Prematurity • OK to augment • Intertwin interval • Monitor both fetuses • External cephalic version • Epidural anesthesia Vaginal Delivery of Twins Twins Influence of Presentation Changing Mode of Delivery • Vertex/vertex – most (including ACOG) • Cesarean rate for twins is rising rapidly in the recommend vaginal delivery. USA! • Vertex/nonvertex – results from vaginal • Fewer breech singletons deliver vaginally delivery are comparable to cesarean. loss of experience for breech twins • Nonvertex twin A – vaginal delivery safe • Practice of defensive medicine but experience limited. 5 Twins Delivery N = 466 Vertex/Vertex = 232 (50%) Vertex/Nonvertex = 124 (27%) Nonvertex Twin A = 110 (23%) Feldman OG 4/06 Twins Basic Philosophy of Delivery Twin Delivery Vertex/Nonvertex c/s 1999 71% • Try to deliver both twins by the same route c/s 2004 95% (preferably vaginally) Vertex/Vertex • Optimize maternal and neonatal outcomes c/s 1999 38% c/s 2004 68% Feldman OG 4/06 6 Undesirable Outcome: Cesarean Delivery Cesarean Delivery of for the Second Twin Twin B Only • Secondary analysis of MFM network data • Failure of descent C- • 1028 C-sections for twins after onset of labor • Persistent malpresentation • 179 Combined vaginal/cesarean deliveries • Cord prolapse • No difference in neonatal adverse outcomes • Hemorrhage • Conclusion: Don’t forego attempting vaginal • FHR abnormalities delivery for fear of cesarean of second twin Alexander • Incredible shrinking cervix OG 10/08 Residents Must Acquire My Question Specific Skills • Forceps delivery What about the mother? • Intrauterine manual dexterity • Total breech extraction • Internal podalic version Yeomans April 2009 • Piper forceps to the aftercoming head 7 8 Vaginal Delivery of Twins • Try to avoid ECV – increased cesarean risk • No benefit of c/s over vaginal delivery, so why not try to avoid an unnecessary cesarean? • Delay increases risk of combined delivery, so we STRONGLY recommend IMMEDIATE delivery of twin B • Internal podalic version is an essential skill Carroll, Yeomans Clin OG 3/06 Neonatal Outcomes of Twin Pregnancy N=758 Consecutive sets of twins ≥ 35 weeks Twin A : all cephalic Pl d i l 657 Planned vaginal: 6 Delivered vaginal: 515 D li d i l 1 Cesarean after labor: 142 Planned cesarean: 101 Cesarean for B only: 3 Schmitz OG 3/08 9 Neonatal Outcomes of Twin Pregnancy Mean intertwin delivery intervals = 4.9 ± 3.2 min. Composite neonatal morbidity for twin B 5% for planned cesarean 4.7% for planned vaginal Schmitz OG 3/08 Twins: February Green Accompanying Editorial N=287 • “Recommended” (Schmitz) vs “offer” (Fox) • Active second stage management • In the Fox study, >50% underwent planned c-section • No combined deliveries How were women counseled? • H l d? • Residents NEVER the primary operator • Prerequisite: Obstetrician skilled in • Did not report number of IPV intrauterine manipulation • Allowed women to choose elective C/S • “If future generations of obstetricians are not trained…C/S rate will increase” Fox et al D’Alton OG Feb 2010 OG Feb 2010 10 Infant Morbidity and Mortality with Vaginal Delivery of Twins There is NO diagnosis of twins • 71% of twins delivered by C/S in 2005 • There are only monochorionic or dichorionic (was 54% in 1995) twins y (1995- ( • Analyzed all twin births > 30 weeks (1995- g g • RCOG guidelines call for diagnosis of 2000) chorionicity by first trimester ultrasound • Conclusion: M+M similar for vaginal and • Monochorionic twins are high risk – cesarean ultrasounds every two weeks • Morbidity does not correlate with birth Moise weight discordance. AJOG Jul 2010 Peaceman AJOG 4/09 Management of Twins MC-DA Twins Unique Complications N = 236 Ongoing pregnancies at 24 wks EGA • Weight discordance pp preterm • Results do NOT support elective p • Discordance for anomalies delivery to prevent IUFD in uncomplicated MC-DA twins MC- • IUFD of one fetus • BUT…no data on route of delivery • PPROM Smith et al • Delayed delivery of one twin AJOG Aug 2010 11 Twins Unique Complications • Monoamniotic twins • Conjoined twins Twin- • Twin-Twin Transfusion • Acardiac twin (TRAP sequence) • Fetus/Complete mole Vidaeff AC, Delu AN, Silva JB, Yeomans ER: Monoamniotic Twin Pregnancy Discordant for Body Stalk Anomaly. J Ultrasound Med 2005; 24:1739‐1744. 12 Body Stalk Anomaly Limb-Body Wall Complex Craniofacial defects not present Craniofacial defects present Limb defects, if present, are non-band related (such Limb malformations, associated with amniotic as clubfeet, abnormal rotation, flexion contractures, bands or ring constrictions, are characteristic and hypoplasias) Abnormal umbilical cord (shortening, complete Umbilical cord may be present cord absence, or absence of one umbilical artery) Defective abdominal wall, with abdominal organs outside the peritoneal cavity covered by an amnioperitoneal membrane adherent to the chorionic plate Kyphoscoliosis, neural tube defects, increased nuchal translucency in 1st trimester Cases are sporadic, no risk of recurrence, karyotype normal Endogenous embryonic disturbance with Primary amnion rupture and vascular disruption is persistence of the extraembryonic coelomic cavity likely pathogenesis Vidaeff AC, Delu AN, Silva JB, Yeomans ER: Monoamniotic Twin Pregnancy Discordant for Body Stalk Anomaly. J Ultrasound Med 2005; 24:1739‐1744. is likely pathogenesis Monoamniotic Twins • May be discordant for anomalies (as in the case just discussed) • Timing and route of delivery - controversial • Remember the picture of the intertwined cords! • Fortunately rare – 1/10,000 13 Recommendations • Start with the major texts • Develop a filing system – include your own cases • Be ready for your opportunity • Acquire/maintain skills 14
"VAGINAL DELIVERY OF TWINS"