Twin gestation Flashcards
Causes of large for dates on examination
- Wrong dates
- Multiples
- Molar
- Uterine pathology
- Polyhydramnios
Which has worse outcomes- monozygotic or dizygotic twins
Monozygotic
+pregnancy loss
Preterm delivery
Perinatal morbidity and mortality
Screening tests in twin pregnancy- accuracy differences
- Fetal nuchal translucency performed with good accuracy, however the CFTS and biomarkers have less accurate risk stratification for twins.
- Risks for down syndrome based on age also less accurate
- Amniocentesis at 15-16 weeks, CVS can also be done->has +risk of spontaneous abortion
- 18 week morphology scan
Information to provide for early pregnancy
- Generally everything that happens in single pregnancy is more pronounced in twins
- Consider stopping work at 28-30 weeks
- If at 8 weeks 2 fetal hearts visible, likely to continue, miscarriage unlikely at that stage
- Vaginal birth good possibility, although increased risk of C section in some.
- Morning sickness should improve after 12 weeks. Eat small regular meals
- Take iron and folate
Finishing the initial consult
- Order normal pregnancy investigations
- Information about support groups
- Considerations for ongoing family planning
- Review when results are back
- Referral to hospital/midwife care- whichever is decided
Multiple gestation complications->mneumonic
The Ps of Multiple Gestation Complications Increased rates of: Puking Pallor (anemia) Preeclampsia/PIH Pressure (compressive symptoms) PTL/PROM/PPROM Polyhydramnios Placenta previa/abruptio PPH/APH Prolonged labour Cord Prolapse Prematurity Mal Presentation Perinatal morbidity and mortality Parental distress Postpartum depression
Maternal complications
Hyperemesis gravidarum GDM Gestational HTN Anemia \++Physiological stress Compressive C/S
Utero-placental complications
PROM/PTL PolyH PP PL Abruption PPH (atony) Umbilical cord prolapse Cord anomalies
Fetal complications
Prematurity IUGR Malpresentation Congenital anomalies TTT Increased perinatal morbidity/mortality Twin interlocking (breech + vertex) Single fetal demise
Increased antenatal screening
USS every 2-3 weeks from 28 weeks to assess growth, may be further ++ if MCDA, MCMA
Vaginal vs C/S
Can attempt vaginal delivery if first twin is vertex, however often second twin will need to be delivered as C/S
Types of twin
Dichorionic, diamniotic
Dichorionic, monoamniotic
Monochorionic, diamniotic
Monochorionic, monoamniotic
Risk factors for dizygotic
Drugs Race Advanced maternal age Parity "Fraternal"
Frequency of maternal twins, monozygotic
Occurs in 1 in 250
Timing of divisions in monozygotic->amnionicity and chorionicity
- Division of the ovum between days 0 and 3: Dichorionic, diamniotic monozygotic twins.
- Division between 4 and 8 days: Monochorionic, diamniotic monozygotic twins
- Division between 9 and 12 days: Monochorionic, monoamniotic monozygotic twins.
- Division after 13 days: Conjoined twins.
