A rare case of fetal cardiac hypertrophy developing into acute circulatory insufficiency and fetal compromise in type 1 diabetic pregnancy

Fetal cardiac hypertrophy (CH) in pregnant women with diabetes is believed to be a benign condition. We encountered a rare case of fetal CH in a pregnant woman with type 1 diabetes, which developed into severe fetal circulatory insufficiency and acidemia. Fetal echocardiography at 37-week gestation showed cardiomegaly with a ventricular hypertrophy. Cardiac function was impaired, and pulsed Doppler findings indicated circulatory failure. The patient was diagnosed with fetal compromise due to fetal CH, and a large for gestational age boy was delivered by an urgent cesarean section. Despite myocardial hyperplasia and left ventricular outflow tract stenosis, the neonate was hemodynamically stabilized by fluid resuscitation alone. Although the neonatal course was favorable, we speculated that the neonate was on the verge of death because he was already acidemic at birth. Therefore, comprehensive fetal echocardiography should be performed in pregnant women with diabetes, and clinicians should not miss the optimal timing of delivery.