Evaluation of fetal outcomes in dichorionic diamniotic twins with hypertensive disorders during pregnancy by the fetal middle cerebral artery and umbilical artery doppler.

BACKGROUND

Hypertensive disorders of pregnancy (HDP) is associated with the poor prognosis of dichorionic diamniotic (DCDA) twins. The prediction value of middle cerebral artery (MCA) and umbilical artery (UA) Doppler indices requires exploration.

OBJECTIVE

To investigate the significance of the fetal MCA and UA doppler indices in DCDA fetal outcomes and depict hemodynamic alterations.

METHODS

DCDA twin pregnancies were classified into the normotensive control group (n = 177) and the HDP group [n = 189, with 60 gestational hypertensions (GH) and 129 preeclampsia/eclampsia (PE/EC)]. Maternal and fetal outcomes were compared, the fetal MCA and UA doppler indices were analyzed, including pulsatility index (PI), resistance index (RI), the ratio of peak systolic blood flow velocity to end-diastolic blood flow velocity (S/D), and the mean velocities (Vm), and the cerebroplacental ratio (CPR) was computed for further study. The receiver operating characteristic curve was used to predict and evaluate small for gestational age (SGA) neonates in HDP twin pregnancies.

RESULTS

Significant differences were shown between the HDP group and the normotensive control group in terms of maternal age, gestational weight gain, blood pressure, post 20-week urinary protein, the use of maternal medication utilization (magnesium sulfate, labetalol, dexamethasone), inter-twin growth discordance, and SGA (p < 0.05). In DCDA twins, the fetal MCA doppler indices (PI, RI and S/D) increased initially and then declined, UA indices (PI, RI and S/D) were declining, and both the Vm of MCA and UA were going up. In late DCDA twin pregnancies with GH, UA Doppler moderately predicted SGA neonates; in those with PE/EC, CPR did the same values (p < 0.05).

CONCLUSION

In DCDA pregnancies complicated by hypertensive disorders, SGA twins exhibit distinct doppler deterioration patterns. Implementing customized monitoring strategies based on the fetal MCA and UA indices can effectively predict adverse conditions, enable timely interventions, and ensure fetal health.