Delivering Twins - Perils & Pitfalls

1. Delivering Twins- Perils & Pitfalls

2. Prof. Dr. Suchitra N. Pandit MD, DNBE, DFP, FRCOG, FICOG, B.Pharm Consultant Obstetrician & Gynaecologist Kokilaben Dhirubhai Hospital, Mumbai ,India Clinical secretary –MOGS, Vice President - FOGSI (2008-09) Chairperson -Young Talent promotion committee FOGSI (2003-07)

3. Fact file • Ovum is fertilized by a sperm & a zygote is formed • If cell mass of zygote gets divided in first 3 days after fertilization - dichorionic diamniotic twins

4. Division between 3 & 5 days after fertilization - monochorioinic diamniotic twins • Division between 5 & 8 days after fertilization - monochorioinic monoamniotic twins • Division after 8 days - conjoint twins

5. Multiple Pregnancy • Incidence • Monozygotic twins - 3.5-5% • Dizygotic twins; depends on - • Race • Parity • Use of ART (assisted reproductive technology)

6. What contributes to the perils of multiple pregnancy Maternal • Exaggerated early symptoms (nausea, vomiting) • Increased miscarriage risk • Vanishing twin syndrome • Increased minor disorders of pregnancy (back-ache, leg pain, inability to walk properly) • Anemia • Preterm labor and delivery (PTL) • Risk of hypertensive disease • Ante partum hemorrhage (APH)

7. Hydramnios, preterm labour • Need for antenatal hospitalization • Single fetal death • Risk of operative delivery • Increased risk for C/S • Postpartum hemorrhage (PPH) • Postnatal problems

8. Concerns – Higher Fetal Risks • Still birth/ neonatal death • Single fetal death in twin pregnancy • Preterm labor and delivery • IUGR (intrauterine growth restriction) • SGA (small for gestational age) • Higher risks of congenital anomalies • Conjoint twins (not seen frequently now ..Thanks to ultrasound) Acardiac twin

9. Risk of cord accidents • Chorionicity • Risk of asphyxia • Operative vaginal delivery • Twin entrapment (during delivery) Congenital anomalies in twin pregnancies • NTD (neural tube defects) • Cardiac anomalies • Bowel Atresia • Conjoint twins • TRAP sequence (twin reversed arterial perfusion)

10. Chorionicity • 2/3 monozygotic are monochorioinic • 2% monozygotic are monoamniotic • Risk of cord accidents is increased • Twin to twin transfusion syndrome • Interlocking at birth

11. Pseudo amniotic twins (with inadvertent puncture of separating amniotic membrane during amniocentesis) • Acute Hydramnios • Stuck twin phenomenon • 8% of twin pregnancies • More in monochorioinic diamniotic • Fetuses are oligo/ polyhydramniotic due to TTTS, aneuploidy, congenital infection, uteroplacental dysfunction and structural malformations • Mortality for both twins is high ( 80% )

12. Twin to twin transfusion syndrome (TTTS) • Placental vascular anastomosis between both fetal placentae • 76-98% of monochorioinic twins • Discordant fetal size & amniotic fluid volume between both fetuses • Recipient twin - Polycythemia , hypervolemia ,polyhydramnios • Donor twin - anemia/ hypovolemia/ oligohydramnios &IUGR • Ascites, pleural effusion, pericardial effusion may develop in both twins • Mortality if syndrome occurs early at 18-26 weeks - 79-100%

13. Management • Prepregnancy- discuss twin pregnancy risk with ART etc • Prenatal • Frequent visits (every 2 weeks or more often) • Folate supplementation • Iron supplements in early second trimester • Anomaly scan at 18-20 weeks • Check Chorionicity / amniocity • Educate the patient

14. Frequent USG evaluations every 3-4 weeks • Umbilical artery Doppler etc as required • Rest in lateral decubitus for min 2 hrs each morning & afternoon ; sleep for 10 hrs atleast each night • Frequent vaginal examination • Careful monitoring throughout antenatal period

15. In cases of one fetal death, check well being of second twin & look for coagulopathy • If hydramnios develops -therapeutic amniocentesis • If delivery is planned or anticipated at < 34 weeks give corticosteroids • Discuss with parents mode of delivery / methods of analgesia available

16. Prevention of Preterm Birth • Bed rest - lateral position, reduced pressure on cervix & increase in uteroplacental blood flow • Should begin at approx 24 weeks & continue till 34 weeks • Prophylactic tocolytics- prevent cervical changes & inhibit uterine contractions . RCTs of tocolytic drugs administered to asymptomatic women for prevention of preterm labor → not effective • Cervical assessment : measurement of cervical length. No evidence that routine U/S for cervical length will lead to interventions that can prevent preterm birth • Cervical cerclage : RCT of prophylactic cerclage in twin pregnancies → no benefit • Fetal fibronectin to assess risk of preterm labour.Routine fFN testing of asymptomatic women is not recommended

17. Optimal time of delivery ? • Singleton pregnancy mostly deliver between 39 – 40 weeks • Twins deliver between 37 - 38 weeks • Corresponding nadir in triplets is 36 weeks • Fetal lung maturity occurs at an earlier gestation in multiple pregnancy • Fetal monitoring should be performed between 35 – 38 weeks in case of twins • Postmaturity is uncommon

18. Concerns about labour/ delivery management • Induction of labor in cases of : PIH, IUGR • Preterm labour/PPROM -Steroids for lung maturity • Risk of APH (Ante partum hemorrhage) • Risk of PPH (Postpartum hemorrhage) • Continuous fetal heart monitoring for both twins • Epidural analgesia • Mode of delivery depending on presentations & other associated risk factors. IVF pregnancies end up having a CS due to high premium attached to them

19. How to avoid perils of delivery • Careful consideration of • Gestational age • Weight of twins • Chorionicity • Presentation of twins : Nine possible combinations 1. Vertex-vertex 2. Vertex-breech 3. Breech – vertex 4. Breech – breech 5. Vertex - transverse Others….

20. Decision for route of delivery depends on : • Vertex -Vertex - 42 % • Vertex - nonvertex : 45 % • Non vertex - non vertex :13 %

21. Prerequisites for Safe Delivery • Knowledge of lie, presentation & weight of each fetus • Portable ultrasound scanner & a CTG with dual monitors • Preferable to monitor one fetus externally & other internally by scalp electrode • Intravenous access • Availability of cross matched blood • Two skilled obstetricians & neonatologists • Continuous epidural analgesia is a good option due to frequent manipulative procedures • Lithotomy position

22. Latent phase • Active phase Hypotonic uterine dysfunction Hypocontractility after delivery of first twin Deliver with uterine contractions, tendency for uterine inertia & prolonged active phase Active management of third stage of labor Availability of oxytocics like oxytocin, prostaglandins… Aseptic technique Postpartum hemorrhage Labour

23. CTG with dual monitoring capability Delivery bed with lithotomy stirrups Forceps or vacuum Oxytocin infusion Tocolytic agent for uterine relaxation Methergin, 15-methyl PGF2 alpha Immediate availability of blood Access for emergency C/S

24. Vertex-Vertex • Aim for vaginal delivery. 70 % deliver vaginally, 20 % LSCS • After delivery of first twin clamp umbilical cord of twin A & do a PV & USG if necessary • 2nd twin is at a much greater risk • Presentation may change so reconfirm • External version if necessary (Not many are trained for this) • External manipulation of twin B if short period of uterine quiescence . May require an Oxytocin IV infusion to resume uterine contraction (if no contraction within 10 min) • Amniotomy when the head engages • If fetal distress– Instrumental delivery (vacuum, forceps) • LSCS for obstetric indication cord prolapse, fetal distress , abruption in 2% of 2nd twin

25. Vaginal Delivery of Second Twin • Time interval between deliveries of twins is important • Longer the interval between delivery, greater is the risk of hypoxia • Oxytocin to be started if labor does not resume within 10 mins of delivery of 1st twin • Mean interval 21 min (2/3 interval < 15 min) • Umbilical cord blood gas deteriorate with increasing time interval – Maximum time limit of 30 min with documentation of reassuring FHR pattern • ACOG 1998 → interval between delivery of twins is not critical in determining the outcome of 2nd twin • Use three clamps, leaving a double clamp on placental side for identification..

26. Vertex-non Vertex • Controversies …. • C/S versus vaginal delivery • No difference in mortality/ morbidity rates • Internal podalic version • External cephalic version of 2nd twin is an option • Breech extraction if version fails ( weight should be >1.5kg) • Informed consent • Anaesthesia , uterine relaxation … • Caesarean section – failed version, fetal distress, cord prolapse or placental abruption … • Same criteria for singleton breech delivery applies for breech delivery of second twin

27. Nonvertex - Nonvertex • Intrapartum management is dictated by presentation of 1st twin • Risk of fetal entanglement – 1st breech & 2nd vertex, - IUGR or demise of one fetus • Bias towards caesarean section • 1st breech – vaginal delivery may be attempted if wt >1.5kg ( LSCS for preterm –no consensus yet ) • Vaginal delivery of first twin - managed like singleton pregnancy • Continuous monitoring of fetal heart of second twin

28. Nonvertex 1st Twin • Limited data to support C/S delivery – Transverse • Breech (EFW < 1500 or > 1500 gm) • Interlocking of fetal heads • Interference of 2nd twin on descent of 1st twin- deflection of head • Inadequately dilated cervix • External cephalic version of 2nd twin • Cesarean delivery of 2nd twin • Cesarean delivery of both twins • ACOG recommends C/S delivery of a nonvertex presenting 1st twin

29. Complications of Breech Vaginal Delivery • Fetal anoxia • Fetal injury (dislocated hips) • Head entrapment • Inadvertent hand delivery with shoulder presentation • Placental abruption • Cord accidents • Endometritis • Maternal trauma ; ruptured uterus

30. Fetal Head Entrapment • Avoided by LSCS • If occurs at vaginal delivery - Try pushing presenting twin up to release chins or to deliver second cephalic twin first !!!!!!! (hypothetical ) Complications of head entrapment • Death of first twin • Asphyxia of both twins • Maternal risk - LSCS, general anesthesia

31. Vaginal Breech Extraction of 2nd Twin • Observational, non-RCT study show there is no increased risk of adverse neonatal outcome. Success rate > 95% • Only 1 RCT prospective – Maternal fever (11.1% versus 40.7%) • Postpartum hospitalization (4.9 vs 8 days) • Neonatal hospitalization (8.0 vs 13.1 days) • Operator must be experienced in vaginal breech delivery • Should be avoided if - EFW of Twin B > Twin A by 500 gm • EFW of Twin B < 1500 gm • Emergency conditions – Total breech extraction • LSCS

32. External Cephalic Version of 2nd Twin • An alternative for fetuses that is not a candidate for vaginal breech delivery • Literature review– 5 series reviewed, 118 patients • Successful vaginal deliveries (58% vs 98% in breech extraction) • Complications (10% vs 1% in breech extraction) • Cord prolapse (5% vs 0.3% in breech extraction) • More likely to undergo abdominal delivery than breech extraction

33. Comparison of BE of 2nd twin, ECV of 2nd twin, C/S of both twin • Healthy newborn– BE > ECV and C/S • Ventilator requirement– C/S > ECV> BE • Length of stay– C/S > ECV> BE • Charges – C/S > ECV> BE • Vaginal breech extraction of nonvertex 2nd twin provides equivalent, if not superior, outcomes at a lower cost

34. Caesarean Delivery • C/S does not eliminate the possibility of a technically difficult or traumatic birth • Type of uterine incision should be based on– Size and weight of twins • Skill of the operator • Degree of development of lower uterine segment

35. Third stage • Most dangerous • Risk of PPH • Large placenta – longer time to separate • More profuse bleeding • May occupy lower segment ( insufficient retraction ) • Uterine inertia following over distention of uterus • Active management of 3rd stage, use of oxytocics

36. Caesarean Delivery of Both Twins Vaginal breech delivery of 2nd twin increase risk of mortality C/S delivery is associated with the lowest rate of neonatal morbidity and mortality

37. Internal Podalic Version • To do or not to do ?? • Experienced operator • EFW > 1500 gm • Adequate liquor • Available anesthesia for • effective uterine relaxation • Simultaneous preparation • for emergency C/S

38. Interlocking Twins

39. Combined Delivery • No one intentionally plans a combined delivery • The worst of both the worlds – a tiring & an often risky pregnancy , a tiring labor followed by a major abdominal operation • Two new babies to care for • Incidence is 9.5% , 1/3 of vertex- non vertex twin • Increased LSCS rate, increase combined delivery • If for whatever reason – safe vaginal delivery of twin B cannot be expected a LSCS is a better option

40. Special Cases Twins with previous scar • Trial of scar if twins has a first vertex should not be an absolute contraindication • Judicious external or internal manipulations are not contraindicated • Prefer caesarean if tranverse / breech ? • Success rate 30-75% • Risk of uterine rupture is the same as VBAC in a singleton pregnancy

41. Management of Mono Amniotic Twins Timing / mode of delivery !!!!!! Antenatal hospitalization Fetal heart monitoring & cord entanglement diagnosis Greatest risk for intrauterine fetal death is at < 30 wks Labor / vaginal delivery do not increase perinatal death Risk of cord of twin B being inadvertently clamped during delivery of twin A in case of vaginal delivery Patient should be informed about complications Best delivered by elective caesarean section

42. Preterm Twins • Double dilemma ! • Prematurity with twins… • Vertex-Vertex • Vertex-Nonvertex– Increase perinatal asphyxia & birth trauma in very low birth weight twin with vaginal breech delivery Points to be considered – • Vaginal delivery or caesarean section • Weight of babies • Gestational age • Presentation • Competent obstetrician & assistants • Neonatal facilities

43. Caesarean section Lower segment is poorly formed so a wider incision to avoid incision dystocia more so in breech • Additional emotional support & financial burden • Psychological support ACOG concludes that C/S of nonvertex 2nd twin EFW< 1500-2000 gm is an appropriate management option

44. Demise of One Fetus in Twins • Management depends on – • Gestational age at the time of death • Cause of death • Chorionicity • If dichorionic & cause of death is intrinsic to affected twin - well being of survivor twin is not jeopardized • Monitoring of maternal platelets & fibrinogen ?? • If cause of death is unknown; very close observation of survivor twin !

45. Death of One of the Twins when Monochorioinic Leads to - • Microcephaly / hydrocephaly • Cerebral palsy / atrophy • Limb reduction deformities • Intestinal atresia • Renal necrosis • Pulmonary / Hepatic / splenic infarcts

46. TRAP Sequence - Management • One twin pumps blood into other twin’s circulation through a connection in their circulations • Pump twin is oligohydramniotic • Recipient twin is polyhydramniotic & develops cardiac failure due to increased volume in his circulation Management options • Closely observe pump twin • Control amniotic volume to reduce preterm labor • Occlude circulation of parasitic acardiac twin • Prepare for possibility of obstructed labor

47. Twin to twin transfusion syndrome (TTTS) • Rare event • Almost exclusive to monochorioinic twins • Stuck – twin • Discordant haemoglobin > 5 g /dl • Discordant weight > 15% difference between both fetal weights • Acute or chronic

48. Acute TTTS – Hyper viscosity & hypotension • Chronic TTTS - Pulmonary hypertension / cardiomyopathy / hydrops & preterm delivery • Carries high perinatal mortality & morbidity >90% • Usually diagnosed antenatally • H/ o maternal infection / sudden increases in fundal height • USG to check chorionicity • Look for discordant growth & / or fetal abnormality

49. Heart of recipient twin is hypertrophic with diminished contractility & A-V valve regurge • Doppler USG - difference in S/D ratios • Fetal blood sampling (FBS) – • Done if diagnosis at < 25 weeks to check fetal hemoglobin level • Sample both twins • Look for fetal infection • Parvovirus and CMV • Look for uteroplacental insufficiency • Mortality rate 79-100% if untreated

50. Chorionicity • Dichorion : twin peak sign (lambda sign), • thick dividing membrane (> 2 mm) • separate placenta • Monochorion : T sign • Zygosity • Genetic testing • Sex