Cognitive Functions of the Fetus.

The human brain is intricately designed to execute cognitive functions, such as perception, attention, action, memory and learning. The complete nervous system is active during prenatal development and the aim of this review is to present data on fetal cognitive functions. The fetus processes sensory stimuli at a cortical level, including painful stimulus, from about 25 weeks of gestation onwards. At gestational week 34, the fetus is able not only to perceive complex acoustic external sounds but also to discriminate between different sounds. Fetal action planning is established by 22 weeks and investigations using four-dimensional ultrasound reveal that complexity of fetal motor action and behavior increases as pregnancy progresses. The capacity of the fetus to learn and memory are prodigious. At term, subcortical structures of the brain are well developed. There is high activity in primary cortical areas and low activity in association areas. Clinically relevant data on cognitive functions of the fetus could be important for the management of fetal pain and treatment of preterm infants as well as for improved neurodevelopmental outcome of fetuses from high-risk pregnancies. Finally, the brain's developmental journey, including development of cognitive functions, continues with the same intensity in the postnatal period.

Early functional and morphological brain disturbances in late-onset intrauterine growth restriction.

AIMS: To determine whether the brain disturbances develop in late-onset intrauterine growth restriction (IUGR) before blood flow redistribution towards the fetal brain (detected by Doppler measurements in the middle cerebral artery and umbilical artery). Further, to evaluate predictive values of Doppler arterial indices and umbilical cord blood gases and pH for early functional and/or morphological brain disturbances in late-onset IUGR. STUDY DESIGN: This cohort study included 60 singleton term pregnancies with placental insufficiency caused late-onset IUGR (IUGR occurring after 34 gestational weeks). Umbilical artery resistance index (URI), middle cerebral artery resistance index (CRI), and cerebroumbilical (C/U) ratio (CRI/URI) were monitored once weekly. Umbilical blood cord samples (arterial and venous) were collected for the analysis of pO2, pCO2 and pH. Morphological neurological outcome was evaluated by cranial ultrasound (cUS), whereas functional neurological outcome by Amiel-Tison Neurological Assessment at Term (ATNAT). RESULTS: 50 fetuses had C/U ratio>1, and 10 had C/U ratio≤1; among these 10 fetuses, 9 had abnormal neonatal cUS findings and all 10 had non-optimal ATNAT. However, the total number of abnormal neurological findings was much higher. 32 neonates had abnormal cUS (53.37%), and 42 (70.00%) had non-optimal ATNAT. Furthermore, Doppler indices had higher predictive validity for early brain disturbances than umbilical cord blood gases and pH. C/U ratio had the highest predictive validity with threshold for adverse neurological outcome at value 1.13 (ROC analysis), i.e., 1.18 (party machine learning algorithm). CONCLUSION: Adverse neurological outcome at average values of C/U ratios>1 confirmed that early functional and/or structural brain disturbances in late-onset IUGR develop even before activation of fetal cardiovascular compensatory mechanisms, i.e., before Doppler signs of blood flow redistribution between the fetal brain and the placenta.

Intrauterine growth restriction and cerebral palsy.

Intrauterine growth restriction (IUGR) can be described as condition in which fetus fails to reach his potential growth. It is common diagnosis in obstetrics, and carries an increased risk of perinatal mortality and morbidity. Moreover, IUGR has lifelong implications on health, especially on neurological outcome. There is a need for additional neurological assessment during monitoring of fetal well-being, in order to better predict antenatally which fetuses are at risk for adverse neurological outcome. Studies have revealed that the behavior of the fetus reflects the maturational processes of the central nervous system (CNS). Hence, ultrasound investigation of the fetal behavior can give us insight into the integrity and functioning of the fetal CNS. Furthermore, investigations carried out using modern method, four-dimensional (4D) sonography, have produced invaluable details of fetal behavior and its development, opening the door to a better understanding of the prenatal functional development of the CNS. Based on previous observations and several years of investigation, our reaserch group has proposed a new scoring system for the assessment of fetal neurological status by 4D sonography named Kurjak antenatal neurodevelopmental test (KANET). The value of KANET in distinguishing fetal brain and neurodevelopmental alterations due to the early brain impairment in utero is yet to be assessed in large population studies. However, preliminary results are very encouraging.

Prenatal and postnatal neurological evaluation of a fetus and newborn from pregnancy complicated with IUGR and fetal hypoxemia.

In this case report, we present prenatal and postnatal neurological evaluation of a fetus and newborn from pregnancy complicated with intrauterine growth restriction, fetal hypoxemia, and preterm labor. Despite unfavorable intrauterine conditions, this premature infant showed normal early neurological development that was verified not only by postnatal tests but also with a new prenatal neurological screening test.

The potential of 4D sonography in the assessment of fetal behavior in high-risk pregnancies.

OBJECTIVE: To assess differences of fetal behavior in normal and high-risk pregnancies. METHODS: In the 1-year period (1 January 2007-31 December 2007), four-dimensional ultrasound has been used to assess Kurjak antenatal neurodevelopmental test (KANET) in low- and high-risk pregnancies after randomization in prospective longitudinal cohort study. Based on the KANET scores, the fetuses were considered as normal (≥ 14 points), borderline (6-13), or abnormal (0-5). RESULTS: Comparison of KANET scores in low- and high-risk pregnancies were expectedly statistically significant. The largest incidence of fetuses with abnormal KANET was in the group of fetuses who had siblings with cerebral palsy. The largest incidence of the borderline KANET has been found in the group of fetuses whose mothers had fever during pregnancy. The following parameters of KANET test significantly differed between the fetuses from low- and high-risk pregnancies: overlapping cranial sutures, head circumference, isolated eye blinking, facial expressions, mouth movements, isolated hand movements, isolated leg movements, hand to face movement, finger movements, and general movements. CONCLUSION: KANET test has the potential to detect and discriminate normal from borderline and abnormal fetal behavior in normal and in high-risk pregnancies.

The potential of 4D sonography in the assessment of fetal neurobehavior--multicentric study in high-risk pregnancies.

OBJECTIVE: An evolving challenge for obstetrician is to better define normal and abnormal fetal neurological function in utero in order to better predict antenatally which fetuses are at risk for adverse neurological outcome. PATIENTS AND METHODS: Prenatal neurological assessment in high-risk fetuses using four-dimensional ultrasound applying the recently developed Kurjak antenatal neurodevelopmental test (KANET). Postnatal neurological assessment was performed using Amiel Tison's neurological assessment at term (ATNAT) for all live-borns and general movement (GM) assessment for those with borderline and abnormal ATNAT. RESULTS: Inclusion criteria were met by 288 pregnant women in four centers of whom 266 gave birth to a live-born baby. It was revealed that 234 fetuses were neurologically normal, 7 abnormal and 25 borderline. Out of 7 abnormal fetuses ATNAT was borderline in 5 and abnormal in 2, whereas GM assessment was abnormal in 5 and definitely abnormal in 2. Out of 25 KANET borderline fetuses, ATNAT was normal in 7, borderline in 17 and abnormal in 1, whereas the GM assessment was as follows: normal optimal in 4, normal suboptimal in 20, and abnormal in 1. In summary, out of 32 borderline and abnormal fetuses ATNAT was normal in 7, borderline in 22 and abnormal in 3; GM assessment was normal optimal in 4, normal suboptimal in 20, abnormal in 6 and definitely abnormal in 2. CONCLUSION: The sonographic test requires further studies before being recommended for wider clinical practice.