To study perinatal management and outcomes for monochorionic diamniotic (MCDA) triplet pregnancies.

A retrospective study was conducted to evaluate perinatal management and outcomes of MCDA triplet pregnancies in West China Second University Hospital, Sichuan University from January 2012 to September 2017 including general clinical data, such as maternal age, primipara or multipara, pregnancy condition and prenatal examination, and pregnancy outcomes, such as delivery mode and perinatal outcomes and mortality. Meanwhile, placental and umbilical cord examination were given after delivery to identify the diagnosis of MCDA and umbilical cord entanglement.

A total of 4 cases of MCDA triplet pregnancies included in our study all were primiparae and spontaneously conceived with age between 20 to 28 years. Two cases (No.1 and No.2 pregnant women) had regular prenatal examinations in our hospital and were diagnosed as MCDA triplet pregnancies at 13^{+ 4,} 18^{+ 5} gestational weeks, respectively. They had caesarean section at 32^{+ 3,} 32^{+ 5} gestational weeks and gave birth to six health and survival female babies. And the following-up results showed that all the 6 neonates grew well. And No.3 and No.4 pregnant women were transferred to our hospital due to preterm premature rupture of membranes (PPROM) at 28, 21^{+ 3} gestational weeks, respectively. Both of them did not have regular prenatal examinations. The diagnosis of MCDA triplet pregnancies were made during childbirth. No.3 pregnant woman had cesarean section due to maternal factor at 28^{+ 3} gestational weeks and gave birth to three male live babies. But these three newborns were died in 6 days after birth (1 newborn), 23 days after birth (2 newborns). No.4 pregnant woman gave birth to three dead fetus at 21^{+ 3} gestational weeks for inevitable abortion, and one still fetus (in single amniotic cyst) occurred abortion before admission in our hospital, and two fetuses were complicated with malformations (one fetus had cleft lip and palate, the other one were acardiac). The perinatal mortality of MCDA triplet pregnancies in this study was 11.1% (1/9). The placental and umbilical cord examination of 4 pregnant women were given after delivery, and all confirmed the prenatal diagnosis of MCDA triple pregnancies. The twin fetuses in single amniotic cyst of No.1, No.2, and No.3 pregnant women all had umbilical cord entanglement.

MCDA triplet pregnancies are very rare. To get a better perinatal outcome of MCDA triplet pregnancies, we recommend early diagnosis, regular prenatal examinations, close prenatal monitoring to improve prenatal care, and communication with patients and their families.