Fetal brain development in diabetic pregnancies and normal controls

Changes in fetal intracranial anatomy during maternal pregestational and gestational diabetes

AIM

To evaluate the changes in fetal intracranial structures in pregnant women with pregestational diabetes mellitus (DM) and gestational diabetes mellitus (GDM).

METHODS

The study was conducted prospectively with patients who were grouped as pregestational DM (n = 110), GDM (n = 110), and control (n = 110). Fetal ultrasonographic measurements of widths of posterior lateral ventricles (PLV), cavum septum pellucidi (CSP), cisterna magna (CM), thalamus and transcerebellar diameter (TCD) were recorded and compared.

RESULTS

Fetal PLV, CSP, and CM widths were higher in pregestational DM and GDM groups than in control group, and also higher in pregestational DM group compared to GDM group (p < 0.001). Fetal TCD in the PGDM group was found to be less than both control and GDM groups (p < 0.001). No difference was found between three groups in terms of fetal thalamus size (p = 0.801). Fetal PLV, CSP, and CM values were positively correlated with maternal hyperglycemia, fetal abdominal circumference (AC), and deepest vertical pocket of amniotic fluid (DVP) (p < 0.001). Fetal TCD was negatively correlated with HbA1c and DVP (p = 0.002, p = 0.38, respectively). The optimal cut-off points to identify pregestational DM and GDM were 5.55 and 5.83 mm for PLV, 5.83 and 6.32 mm for CSP, and 7.26 and 6.62 mm for CM.

CONCLUSION

Maternal hyperglycemia was significantly associated with an increase in the widths of fetal PLV, CSP, and CM and a decrease in fetal TCD.

Reference Ranges for Corpus Callosum and Cavum Septi Pellucidi Biometry on Prenatal Ultrasound: Systematic Review and Meta-Analysis

We conducted a systematic review and meta-analysis of published nomograms for fetal corpus callosum and cavum septi pellucid biometry. A structured literature search was conducted to identify studies that reported normal measurements of the fetal corpus callosum and cavum septi pellucidi. Random effects metaanalysis was used to calculate normal ranges, and reference curves are provided. The quality assessment demonstrated that there was generally poor reporting regarding maternal characteristics and neonatal outcomes. Our findings emphasize that standardization of research protocols and publishing criteria for normal biometric ranges is needed.

Central nervous system biometry in fetuses with and without congenital heart diseases

OBJECTIVE

To compare the fetal brain structures assessed in routine sonographic scans during the second and third trimesters in fetuses with and without congenital heart disease (CHD).

METHODS

This is a retrospective cross-sectional single-center study. We measured the head circumference (HC), the transversal diameter of the cerebellum (TCD) and the sizes of the cisterna magna (CM), the cavum septi pellucidi (CSP) and the posterior ventricles (PV) between 20 and 41 weeks of gestation. We compared 160 fetuses with CHD (case group) to 160 fetuses of normal pregnancies (control group). Every patient was matched with a control, considering the gestational age at which the ultrasound was performed. We divided the CHD group into 3 subgroups: retrograde flow in the aortic arch (group 1), right heart anomaly with the antegrade flow in the aortic arch (group 2) and other CHDs with the antegrade flow in the aortic arch (group 3).

RESULTS

The mean width of the PV was larger in fetuses of groups 1 and 3 in comparison to the control group (P < 0.001, P = 0.022; respectively). We found that the APGAR score at 5 min (P < 0.001, P < 0.001; respectively) and gestational age at delivery (P = 0.006, P = 0.001; respectively) were inferior in groups 1 and 3 compared to controls.

CONCLUSIONS

Central nervous system biometry is altered in fetuses with CHD. PV is enlarged in CHD fetuses especially with decreased oxygen levels in the aortic arch.