Multiple Pregnancy DR HAZEM ALMANDEEL OBGYN ROTATIONCOURSE 481

Multiple Pregnancy DR. HAZEM AL-MANDEEL OB/GYN ROTATION-COURSE 481

Introduction A pregnancy with two or more embryos/fetuses that exist simultaneously The perinatal mortality and morbidity are increased disproportionately with number of fetuses Maternal mortality and morbidity are also increased Twin gestation is the most common type

Etiology and Classification of Twinning Occurs as result of the division of one fertilized egg (monozygotic) or fertilization of two eggs (dizygotic). Both processes can occur in other multiple gestation Dizygotic (Fraternal) twins will always have two amnions and two chorions In Monozygotic (Identical) twins, the number of membranes depend on the time of cleavage of the fertilized egg 70% of MZ twins are monochorionic (mostly diamniotic) and 30% are diamniotic dichorionic

Incidence of Twin Preganacy Not constant throughout the world (varies according to race, hereditary factors, maternal age, parity, and the use of fertility agents) Incidence of MZ twins is ≈ 1 per 250 births DZ twins increases with increased family Hx of twinning, maternal age, and increased parity Multiple gestation occurs in 10%-30% of women following the use of induction of ovulation agents Spontaneous triplets is 1 in 8000 pregnancies and quadruplets I in 800, 000. In ART: 1 in 3000 births

Determination of Zygosity Obstetrical ultrasound can often determine zygosity (esp. if done before 14 weeks) Determination of number of amnions and chorions are VERY important for management After delivery, zygosity should be confirmed No. of membranes, no. of placentas and gender are essential in determining zygosity

Abnormalities of Twinning Process Occurs only in monochorionic (MZ) twins Ø Conjoined Twins Ø Twin-Twin Transfusion Syndrome (TTTS) Ø Umbilical Cord Abnormalities

Complications of Multiple Gestation Maternal Anemia Hydramnios Preeclampsia Preterm labour Postpartum hemorrhage Cesarean delivery Fetal Malpresentation Placenta previa Abruptio placentae Premature rupture of the membranes Prematurity Umbilical cord prolapse Intrauterine growth restriction Congenital anomalies

Diagnosis of Multiple gestation Signs and Symptoms: maternal sensation of larger abdomen, sensation of excessive fetal movement, excessive weight gain, palpation of more fetal parts, ausculation of more than one fetal heart Ultrasound should be done routinely in all pregnancies (usually between 18 -20 weeks) Failure of early Dx of multiple gestation leads to increased perinatal morbidity and mortality

Antepartum Management Goal is to minimize perinatal mortality and morbidity and to prevent maternal complications More frequent visits for antenatal care Assessment of the cervical length frequently Bed rest for the mother in the late pregnancy is suggested Fetal surveillance is essential: monthly obstetrical ultrasound in the late pregnancy period and non stress test in the last month

Intrapartum Management Prevention and treatment of preterm labour Patient should be delivered in a hospital with NICU facility Mode of delivery for twins depends on the fetal presentations (Vx/Vx, Vx/Br, Br/Vx, or Br/Br) Time interval between twin delivery is controversial (less than 30 min) For other multiple pregnancy, caesarean section is the safest mode of delivery

Causes of Perinatal Morbidity and Mortality Congenital anomalies Prematurity Birth hypoxia/Asphyxia Respiratory Distress Syndrome Cerebral hemorrhage Birth Trauma Stillbirths Retained dead fetus Syndrome