The aim of this observational study is to evaluate the correlation between new ultrasound patterns and fetal central nervous system (CNS) malformations.

During fetal life, the CNS undergoes major changes, so it is important to study the evolution of brain morphology serially during intrauterine life.

Despite numerous data in the literature, prenatal ultrasound diagnosis of CNS malformations is often difficult due to the presence of imaging pictures that are nondiagnostic or difficult to interpret. Moreover, only some of the sonographic features of CNS malformations have been described in detail. Therefore, it is essential to study and describe the ultrasound pictures in order to identify new ultrasound patterns useful to identify the fetal malformation more clearly. Therefore, this study aims to retrospectively analyze the ultrasound images of fetuses with established brain malformations and compare them with those of healthy fetuses in order to highlight the presence of new ultrasound patterns, which may more clearly define the malformative pathology.

Ultrasound images routinely performed in pregnancy in fetuses with brain malformation and in healthy fetuses will be reviewed.

For each patient, information will be collected on:

• Age
• Previous pregnancies and their outcome
• Pregnancy arising spontaneously or through Medically Assisted Procreation techniques
• Family history of congenital malformation
• Type of central nervous system malformation (neural tube defects, holoprosencephaly, corpus callosum agenesis, cerebellar malformations, posterior cranial fossa cysts, other malformations)
• Gestational age at the time of diagnostic suspicion
• Gestational epoch at the time of diagnosis
• Pregnancy outcome (miscarriage, voluntary termination of pregnancy, spontaneous delivery or cesarean section)
• Presence of associated abnormalities affecting other anatomical districts

For each newborn, information will be collected on:

• Sex
• Weight
• Umbilical artery pH
• APGAR index at 5 and 10 minutes
• Neurological assessment in the immediate postpartum period
• Perinatal mortality

Inclusion Criteria:

• Women older than 18 years with single pregnancy and fetus with ultrasound diagnosis of central nervous system malformation (group A)
• Women with single pregnancy and normoconformed fetuses (group B).

Exclusion Criteria:

• Twin pregnancy

Participants will be divided into 2 groups: group A (patients whose fetus has central nervous system malformations) and group B (healthy patients whose fetus has no anatomical abnormalities of the central nervous system).