L3: Multifetal Pregnancy Flashcards
Def of Multifetal Pregnancy
Pregnancy that results in > 1 fetus.
Incidence of Multifetal Pregnancy
Types of Multifetal Pregnancy
- Monozygotic Twins
- Dizygotic Twins
Percentage of Monozygotic Twins
33%
Synonyms of Monozygotic Twins
Uniovular twins, identical twins or
homologous twins
Incidence of Monozygotic Twins
1/250 of deliveries
Mechanism of Monozygotic Twins
RF for Monozygotic Twins
Not related to risk factors
Characters of Monozygotic Twins
They are similar in sex, morphological features, psychological & mental profile & HLA typing
- Differ in finger prints, iris pattern & voice
Percentage of Dizygotic Twins
67%
Synonyms of Dizygotic Twins
Binovular twins, non-identical twins or
heterologous twins
Incidence of Dizygotic Twins
Varies according to risk factors
Mechanism of Dizygotic Twins
RF for Dizygotic Twins
Related to certain risk factors
Characters of Dizygotic Twins
Sex & morphological features are as
any sisters or brothers
Determination of zygosity
RF for Dizygotic Twins
Complications of Multifetal Pregnancy
- Maternal
- Fetal
Complications of Multifetal Pregnancy During Pregnancy
- Maternal
- During pregnancy
- During Labor
- During Puerperium
Maternal Complications of Multifetal Pregnancy During Pregnancy
Maternal Complications of Multifetal Pregnancy During Pregnancy
- PROM
- 3 times more common than singleton pregnancy specially if associated è polyhydramnios or abnormal presentation.
Maternal Complications of Multifetal Pregnancy During Pregnancy
- APH
- Due to placenta previa (due to large placenta encroaching on LUS) or placental abruption (due to higher incidence of PIH).
Maternal Complications of Multifetal Pregnancy During Pregnancy
- PIH
Usually of early onset.
Maternal Complications of Multifetal Pregnancy During Pregnancy
- Anemia
Due to increased requirements & plasma expansion.
Maternal Complications of Multifetal Pregnancy During Pregnancy
- Malpresentation
Maternal Complications of Multifetal Pregnancy During Pregnancy
- Pressure Manifestations
Maternal Complications of Multifetal Pregnancy During Pregnancy
- Psychological
Due to prolonged rest & hospitalization.
Maternal Complications of Multifetal Pregnancy During labor
Maternal Complications of Multifetal Pregnancy During Puerperium
Fetal Complications of Multifetal Pregnancy
Fetal Complications of Multifetal Pregnancy
- IUFD
- More in monozygotic type than in dizygotic type due to less placental perfusion & increases chance of vascular connections.
Fetal Complications of Multifetal Pregnancy
- Intrapartum Fetal Death
Death of 1st fetus:
- Due to cord prolapse or locked twin.
Death of 2nd fetus:
- Due to excessive sedation, premature separation of placenta, hypoxia, constriction ring or operative manipulation.
Fetal Complications of Multifetal Pregnancy
- IUGR
Due to relatively deficient resources that may affect one fetus > other.
Fetal Complications of Multifetal Pregnancy
- TTTS
….
Fetal Complications of Multifetal Pregnancy
- Increased Incidence of Congenital Anomalies
- Major anomalies develop in 2% & minor anomalies develop in 4% of twins.
- Incidence in monozygotic type is twice that in dizygotic type.
- Incidence increaeses in monoamniotic type.
Fetal Complications of Multifetal Pregnancy
- umbilical Cord Problems
Fetal Complications of Multifetal Pregnancy
- Cerebral Palsy
- times more common in twins than in singleton pregnancy & it occurs due to single fetal demise, IUGR, discordant growth or TTTS.
Fetal conditions unique to multifetal pregnancy
- Vanishing Twin syndrome
- Single fetal Demise
- Discordant Growth
- TTTS
- Conjoint Twins (Siamese twins or disomata)
- Locked Twins
- Retained 2nd Twin
Def of Vanishing twin syndrome
- 1st trimesteric spontaneous loss or arrest of development è subsequent resorption of at least 1 embryo or fetus which was viable & previously confirmed ultrasonically.
Dx of Vanishing twin syndrome
- Viable multifetal pregnancy is diagnosed by ultrasound in ist trimester & not confirmed on later ultrasound examination.
Def of Single fetal demise
- Death of 1 fetus remote from term but pregnancy continues è ≥ 1 living fetus.
Incidence of Single fetal demise
6% of twins.
RF for Single fetal demise
Monochorionicity, same sex fetuses & weight discordancy.
Complications of Single fetal demise
Def of Discordant Growth
Size inequality of fetuses that may be sign of pathological UGR in one fetus.
Incidence of Discordant Growth
10-15% of twins.
Etiology of Discordant Growth
Complications of Discordant Growth
- Increased incidence of congenital anomalies.
- Physical & intellectual sequels late in life.
Dx of Discordant Growth
- ≥ 15% difference in estimated fetal weight by ultrasound (larger twin is used as index)