Outcomes
Maternal and pregnancy outcomes examined included gestational diabetes
mellitus (GDM), preeclampsia or HELLP syndrome (hemolysis, elevated
liver enzymes and low platelets syndrome), intrauterine death (IUD) of
at least one twin, cesarean or vaginal delivery, wound healing
disorders, postpartum hemorrhage (PPH), including those in need of blood
transfusions, uterine atony with the necessity of Sulprostone or a
tamponade, and preterm birth.
GDM was diagnosed according to the guidelines of the American Diabetes
Association. Every gravida underwent a 75 g oral glucose tolerance test
between 24 and 28 weeks of gestation. GDM was diagnosed when at least
one limiting value was exceeded (fasting: 92 mg/dL, 1 hour: 180 mg/dL, 2
hours: 153 mg/dL). Preeclampsia was defined according to the Practice
Bulletin of the American College of Obstetricians and Gynecologists
(ACOG) as a blood pressure of ≥140/90 mmHg and proteinuria or at least
one sign of organ damage. IUD was defined according to the Royal College
of Obstetricians & Gynaecologists as missing signs of life in utero
after 24 completed weeks of gestation. PPH was defined as bleeding
>1,000 ml or blood loss with signs of hypovolemia within 24
hours after birth. Gestational age was calculated through measurement of
the fetal crown-rump length using ultrasound and categorized into groups
of ≤27+6, 28 – 31+6 and 32 – 36+6 weeks of gestation.
Neonatal outcomes analyzed were birth weight discordance between twins,
admission to the neonatal intensive care unit (NICU), pH of the
umbilical artery and an APGAR score value below seven after five
minutes.
Birth weight discordance was defined according to Practice Bulletin of
the ACOG, estimated for every neonate, and classified into three groups
of <20%, 20 – 24,9% and ≥25%. Fetuses with a birth weight
discordance above 20% were monitored more intensively. Admission to
NICU was defined as admission of at least one twin. The arterial
umbilical pH was subdivided into categories of ≤7.0, 7.01 – 7.1 and
7.11 – 7.2.