Fetal abnormalities leading to termination of twin pregnancies: the 17-year experience of a single medical center

Prenatal Diagnosis of Structural Anomaly Among Singletons and Twins: Eight-Year Experience in a Chinese Tertiary Center

OBJECTIVES

This study was designed to reveal structural abnormalities in singleton and twin pregnancies in the Chinese population.

METHODS

This retrospective study spanned 8 years and included 1228 singleton pregnancies (112,919 examinees) and 49 twin pregnancies (1865 examinees) with structural anomalies diagnosed by ultrasound. Detailed descriptions of anomalies, gestational weeks at diagnosis, and maternal age were recorded. The odds ratio was evaluated in twin pregnancies with detectable structural anomalies.

RESULTS

The annual average "ultrasound prevalence of fetal anomalies" among singleton and twin pregnancies were 1.09 and 3.06%, respectively. Mothers with twin anomalies were older (P < .001), and twin pregnancies were diagnosed with anomalies in earlier gestational weeks than singleton (P = .011). No differences were found in the types of anomalies between singleton and twin pregnancies. Central nervous system anomaly was the most common type in singleton and twin pregnancies. Twin pregnancies had higher rates of major anomalies than singleton (total OR 2.45), especially cardiovascular, central nervous, and gastrointestinal systems and ear/eye/face/neck disorders.

CONCLUSIONS

Compared with singleton, twin pregnancies had higher odds of detectable structural anomalies. Twin pregnancies with structural anomalies were diagnosed at earlier gestational age and associated with older maternal age. Central nervous system anomaly was the most common type in singleton and twin pregnancies.

[Perinatal issues of biamniotic twin pregnancies depending on gestational ages of selective termination]

OBJECTIVES

A severe fetal abnormality is found in 1-2% of biamniotic twin gestations leading to the dilemma of expectative management or selective termination of the defective fetus. The primary objective of our study was to determinate the relationship between perinatal outcomes and gestational ages of selective termination.

METHODS

We conducted a single-center retrospective and observational study which reviewed 58 biamniotic twin pregnancies that underwent selective termination for discordant fetal anomalies between January 2006 and September 2017. Fetal anomalies, ages of diagnostic and selective termination, perinatal outcomes were noted.

RESULTS

Selective terminations realised before 20 weeks (group A) were complicated by 8,7% of fetal loss and 28,6% of prematurity, of which 14,3% before 32 GA. In group B (selective termination planned between 20 and 32 weeks), there was no fetal loss but 40% of prematurity of which 13,3% before 32 GA. In group C (selective termination planned after 32 weeks), there was no fetal loss, but 42,1% of prematurity, and one birth before 32 GA (5%).

CONCLUSIONS

Gestational age of a selective termination should be determined together with the parents, after informing them about the risks and technical difficulties at each gestational age.

Termination of pregnancy due to fetal central nervous system abnormalities performed after 24 weeks' gestation: survey of 57 fetuses from a single medical center

PURPOSE

To assess fetal central nervous system (CNS) abnormalities presenting as major findings leading to late termination of pregnancy (late TOP) performed ≥ 24 weeks' gestation.

METHOD

The study population included 2789 pregnant women that underwent late TOP in our institute between the years 1998 and 2015.

RESULTS

Fifty-seven cases (2.0%) underwent late TOP because of fetal CNS indications and are the subjects of the current study. Those cases were subdivided into four categories (1) no routine prenatal screening with an incidental finding discovered ≥ 24 weeks' gestation (25 patients, 43.8%); (2) developmental or acquired findings detected during late second and third trimester (22 patients, 38.6%); (3) apparently normal routine screening with abnormal findings that could have been detected earlier (six patients, 10.6%); (4) routine prenatal care raised suspicion of abnormalities, and the final diagnosis was established only following additional tests (four patients, 7.0%).

CONCLUSIONS

Combining the two categories of CNS abnormalities, i.e., pregnant women who did not undergo any fetal evaluation (group 1) and those that could have been detected earlier (group 3) consists 54% from our cohort in which late TOP could have been avoided. On contrary, 39% fetuses from our study population had CNS developmental findings which could be detected only at advanced stage of gestation.