The goal of this study is to describe the maternal hemodynamic parameters detected by UltraSonic Cardiac Output Monitor (USCOM®) in women carrying a fetus with a congenital heart disease (CHD) and to possibly describe an association between those parameters and the presence of a fetal cardiac anomaly.

It will also learn about:

• the number of cases of preeclampsia in our population of women carrying fetuses with CHD
• the relationship between maternal hemodynamic profile and maternal and perinatal outcome
• the associations between maternal hemodynamic parameters and the specific heart defect subtype
• the relationship between maternal hemodynamic parameters and fetal cardiac parameters in our population.

The haemodynamic evaluation will be performed at the time of diagnosis of CHD and then every two weeks until delivery. A further evaluation will be performed immediately after delivery (within 72 hours).

The following maternal hemodynamic indices will be evaluated: heart rate (HR) (beats per min; bpm), mean arterial pressure (mmHg), stroke volume (mL), cardiac output (CO) (L/min), systemic vascular resistance (dynes/s/cm5). Data on the demographic and pregnancy characteristics of participants, hemodynamic and ultrasound investigations, perinatal and delivery features will be also collected. In particular, the following variables will be included in the study: type of congenital heart defect, gestational age at diagnosis, fetal weight (EFW) and fetal weight centile at diagnosis of CHD and at the last scan before delivery, mean uterine arteries pulsatility index (UtA-PI), fetal umbilical artery (UA-PI) and middle cerebral artery pulsatility index (MCA-PI) at diagnosis and at the last scan before delivery, maternal age, height, pre-pregnancy weight and gestational weight gain, systolic and diastolic blood pressure values (maximum and minimum values), presence of proteinuria, biochemical maternal assessment (maximun and miminum values of creatinine and uric acid level, platelet count, liver enzyme level), incidence of hypertensive disorders of pregnancy, antihypertensive drug administration (type and dosage) including magnesium sulfate, antenatal steroid administration, mode of delivery and indications, gestational age at delivery, birthweight and birthweight centile, need of respiratory or cardiac support, neonatal intensive care unit admission and number of days, major neonatal complications, maternal morbidities (HELLP, eclampsia, intravascular disseminate coagulation, post-partum hemorrhage), and mortality. The following definitions of hypertensive disorders will be used, according to the International Society for the Study of Hypertension in Pregnancy (ISSHP) 2018 criteria (14): chronic hypertension (CH) will be defined as hypertension (≥140/90mmHg) that predates pregnancy or is present prior to 20 weeks' gestation; gestational hypertension was defined as de-novo hypertension (≥ 140/90 mmHg) after 20 weeks' gestation; and preeclampsia (PE) will be defined as de-novo hypertension (≥ 140/90 mmHg) after 20 weeks' gestation with coexisting proteinuria, other maternal organ dysfunction or fetal growth restriction; preeclampsia superimposed to chronic hypertension (PE-CH).

Inclusion Criteria:

• Informed consent accepted
• Maternal Age ≥ 18 years
• Singleton pregnancy with a viable fetus at >20 weeks of gestation, with a diagnosis of congenital heart disease detected on antenatal ultrasound assessment and postnatally confirmed

Exclusion Criteria:

• Multiple pregnancy
• Pregnancy complicated by aneuploidy, genetic syndrome, or major structural fetal abnormality
• Maternal congenital heart disease (GUCH)
• Maternal known cardiac disease