Ultrasound Assessment of Twin Reversed Arterial Perfusion Sequence for the Prediction of Adverse Pregnancy Outcomes in the First Trimester

Objectives: To investigate twin reversed arterial perfusion (TRAP) sequence for the prediction of TRAP-related adverse pregnancy outcomes at the gestational age of 11-14 weeks. MethodsPregnant women in the first trimester diagnosed with TRAP were recruited at West China Second University Hospital from January 2015 to June 2018. Systematic screening for the pump twin’s crown-rump length (CRL) and acardiac twin’s upper pole-rump length (URL) was conducted using ultrasonic detection. The (CRL-URL)/CRL and URL/CRL ratios were used to assess the pregnancy outcomes for the pump twin. ResultsTwenty-one pregnant women aged 21–39 years with a gestation of 11-14 weeks were recruited. TRAP was diagnosed on average (± standard deviation [SD]) at pregnancy week 13.1 ± 0.18. The pump twins’ mean (± SD) CRL was 6.65 ± 1.1 cm. The incidence of intrauterine death for the pump twins was 19.0% (n=4), the miscarriage rate was 14.3% (n=3), and the live birth rate was 66.7% (n=14). The (CRL-URL)/CRL ratios between the non-survival (intrauterine death and miscarriage) and survival groups significantly differed (0.33 ± 0.08 vs. 0.58 ± 0.08, p < 0.05). Similarly, the URL/CRL ratios between the non-survival and survival groups significantly differed (0.67 ± 0.08 vs. 0.42 ± 0.08, p < 0.05). ConclusionsThe (CRL-URL)/CRL and URL/CRL ratios were valuable indicators for determining pregnancy outcomes of pump twins with TRAP at an early gestational age.