Congenital Heart Defects in Twin Pregnancies: A Retrospective Analysis of Clinical Characteristics and Risk Factors

INTRODUCTION: Congenital heart defects (CHDs) are among the most common congenital anomalies. An increased frequency of CHDs has been reported in twin pregnancies. This study aims to determine the frequency, types, and contributing factors of CHDs in twin births.
METHODS: This retrospective study included twin pregnancies in which both fetuses underwent at least one echocardiographic examination at the pediatric cardiology outpatient clinic. Data were collected from hospital records and included maternal age, use of assisted reproductive technology (ART), mode of delivery, pregnancy-related risk factors (gestational diabetes mellitus, preeclampsia, hypertension, and hypothyroidism), gestational age at birth, birth weight, and presence and type of CHD. Data were analyzed using Microsoft Excel.
RESULTS: The study included 498 twin infants (252 female, 50.6%) and 249 mothers. Among the cases, 116 (23.3%) were monochorionic, and 26.1% were conceived through in vitro fertilization, with the remainder being spontaneous pregnancies. A total of 34 infants (6.83%) were diagnosed with CHDs. In four pregnancies, both twins were affected, whereas in the remaining cases, only one twin was affected. Most CHDs consisted of septal defects and right ventricular outflow tract obstructions, whereas 12 cases had more complex anomalies.
DISCUSSION AND CONCLUSION: In line with previous literature, this study found an increased frequency of CHDs in twin pregnancies. No significant difference in CHD frequency was observed between ART and spontaneous twin pregnancies. No specific risk factor was identified as a distinguishing feature between cases with and without CHDs.

Keywords: Congenital heart defect, in vitro fertilization, twin baby, twin pregnancies.