A Systematic Review of Intrapartum Fetal Head Compression: What Is the Impact on the Fetal Brain?

Effects of Fetal Position on the Loading of the Fetal Brain During the Onset of the Second Stage of Labor

During vaginal delivery, the delivery requires the fetal head to mold to accommodate the geometric constraints of the birth canal. Excessive molding can produce brain injuries and long-term sequelae. Understanding the loading of the fetal brain during the second stage of labor (fully dilated cervix, active pushing, and expulsion of fetus) could thus help predict the safety of the newborn during vaginal delivery. To this end, this study proposes a finite element model of the fetal head and maternal canal environment that is capable of predicting the stresses experienced by the fetal brain at the onset of the second phase of labor. Both fetal and maternal models were adapted from existing studies to represent the geometry of full-term pregnancy. Two fetal positions were compared: left-occiput-anterior and left-occiput-posterior. The results demonstrate that left-occiput-anterior position reduces the maternal tissue deformation, at the cost of higher stress in the fetal brain. In both cases, stress is concentrated underneath the sutures, though the location varies depending on the presentation. In summary, this study provides a patient-specific simulation platform for the study of vaginal delivery and its effect on both the fetal brain and maternal anatomy. Finally, it is suggested that such an approach has the potential to be used by obstetricians to support their decision-making processes through the simulation of various delivery scenarios.

Do infants with isolated congenital sixth nerve palsy require comprehensive work-up? A retrospective cohort and review of the literature

PURPOSE

The purpose of this study is to describe a case series of infants with isolated congenital sixth nerve palsy (ICSNP) and suggest a management algorithm based on our experience and a review of the literature.

METHODS

A retrospective cohort design was used. The clinical database of a single tertiary medical center was reviewed to identify all patients diagnosed with ICSNP from January 2020 to November 2022. Data were collected as follows: demographic parameters, age at initial presentation, presenting symptoms and signs, findings on ophthalmic and neurologic examinations, findings on follow-up, and outcome.

RESULTS

Six patients were included. All were born at term. The average gestational weight was 3675.7 ± 262.7 g. Three mothers had gestational diabetes. Five deliveries necessitated labor induction either by oxytocin (n = 4) or by membrane stripping followed by oxytocin (n = 1). One had also gone a forceps assisted delivery. Symptoms were noticed in all newborns by their parents within the first week of life. Ophthalmological and neurological examinations were otherwise unremarkable apart of one patient with a head turn to the side of the involved eye. Four patients underwent brain imaging that were unremarkable. All abduction deficits resolved by 1 to 3 months of age. Follow up examinations were unremarkable (mean follow up 14.3 ± 5.0 months, range 4-23).

CONCLUSIONS

This case series, together with previous reports, support ICSNP's benign nature. We suggest an initial basic work-up that solely includes ophthalmological and neurological examinations which will be elaborated in case of any additional pathologic findings or if ICSNP does not fully resolve by 3 months.

Fetal defenses against intrapartum head compression-implications for intrapartum decelerations and hypoxic-ischemic injury

Uterine contractions during labor and engagement of the fetus in the birth canal can compress the fetal head. Its impact on the fetus is unclear and still controversial. In this integrative physiological review, we highlight evidence that decelerations are uncommonly associated with fetal head compression. Next, the fetus has an impressive ability to adapt to increased intracranial pressure through activation of the intracranial baroreflex, such that fetal cerebral perfusion is well-maintained during labor, except in the setting of prolonged systemic hypoxemia leading to secondary cardiovascular compromise. Thus, when it occurs, fetal head compression is not necessarily benign but does not seem to be a common contributor to intrapartum decelerations. Finally, the intracranial baroreflex and the peripheral chemoreflex (the response to acute hypoxemia) have overlapping efferent effects. We propose the hypothesis that these reflexes may work synergistically to promote fetal adaptation to labor.

Cranial molding on neonates in Ghana: mothers' perspective and their knowledge on potential harm to babies' brain

BACKGROUND AND OBJECTIVES

Traditional cranial molding is an ancient practice prevalent in Ghana. In this work, we aimed at assessing mothers'/caregivers' perspective and their knowledge on potential harm of cranial molding on neonates.

METHODS

Two hundred and one (201) nursing mothers with babies aged 1-12 months were sampled in a cross-sectional study using questionnaires. We assessed the mothers'/caregivers' reasons for cranial molding, their perceived benefits of this practice, and their knowledge about the potential harm this practice pose to babies.

RESULTS

Sixty four percent (64%) of mothers confirmed they practice cranial molding on their babies either on their own or through the assistance of a caretaker. However, 72% of all mothers/caregivers did not know this practice has the potential to harm the baby in any way. Mothers'/caregivers' reasons for this practice included the following: to achieve a more "beautiful" head shape, hasten the healing of the fontanelle, and limit head growth. There was a significant association between the mothers'/caregivers' level of education and the practice of cranial molding (p value < 0.05). However, there was no association between head symmetry and cranial molding (p value > 0.05).

CONCLUSIONS AND IMPLICATIONS

Majority of mothers/caregivers were actively engaged in cranial molding on neonates but remain ignorant about the potential harm this practice could have on their babies. Mothers/caregivers therefore need to be educated about the potential harm posed by traditional cranial molding on neonates.

Neonatal subgaleal hemorrhage unrelated to assisted vaginal delivery: clinical course and outcomes

PURPOSE

The purpose of the study was to evaluate the occurrence of subgaleal hemorrhage (SGH) following non-assisted vaginal delivery (normal vaginal delivery or cesarean delivery), and to characterize associated factors, clinical course, and outcomes, compared to attempted assisted vaginal delivery (AVD)-associated SGH METHODS: A retrospective cohort study was conducted. All cases of SGH encountered following delivery of a singleton neonate at Hadassah, Hebrew University Medical Center during 2011-2018 were included. Maternal, fetal, intrapartum, and neonatal characteristics and outcomes were compared between AVD-related and non-AVD-related SGH groups.

RESULTS

The overall incidence of SGH was 4.5/1000 (369/82,256) singleton deliveries. The incidences of AVD- and non-AVD-related SGH were 44.6/1000 (350/7852) and 0.3/1000 (19/74,404) singleton deliveries, respectively. Ten (53%) of the 19 non-AVD-related SGH were diagnosed after vaginal delivery and 9 (47%) after an urgent cesarean section. SGH severity was mild, moderate, and severe in 68%, 16%, and 16% of the cases, respectively. SGH severity did not differ between the attempted AVD group and the non-AVD-related SGH group. A higher proportion of neonates with non-AVD SGH required phototherapy treatment than did those diagnosed with AVD-related SGH (56% vs. 24%, P = 0.003). Other neonatal outcomes, including Apgar scores, maximal bilirubin level, length of stay, and the rate of composite adverse outcomes, did not differ between the groups.

CONCLUSIONS

SGH, although rare, may be diagnosed after unassisted vaginal or cesarean delivery in the absence of an AVD attempt. We advocate continuing education for all medical staff who participate in peripartum and neonatal care, regarding the possible occurrence of non-AVD-related SGH.

[Circulatory intranatal hypoxia]

The paper considers one of the types of intranatal fetal hypoxia - circulatory hypoxia. It discusses the issues of fetal head configuration during childbirth and the compensatory-adaptive mechanisms when the fetal head passes through the maternal parturient canal. The relationships and differences between circulatory hypoxia and birth trauma are investigated.

Obstetrics at Decisive Crossroads Regarding Pattern-Recognition of Fetal Heart Rate Decelerations: Scientific Principles and Lessons From Memetics

The survival of cardiotocography (CTG) as a tool for intrapartum fetal monitoring seems threatened somewhat unjustifiably and unwittingly despite the absence of better alternatives. Fetal heart rate (FHR) decelerations are center-stage (most important) in the interpretation of CTG with maximum impact on three-tier classification. The pattern-discrimination of FHR decelerations is inexorably linked to their nomenclature. Unscientific or flawed nomenclature of decelerations can explain the dysfunctional CTG interpretation leading to errors in detection of acidemic fetuses. There are three contrasting concepts about categorization of FHR decelerations: 1) all rapid decelerations (the vast majority) should be grouped as “variable” because they are predominantly due to cord-compression, 2) all decelerations are due to chemoreflex from fetal hypoxemia hence their timing is not important, and 3) FHR decelerations should be categorized into “early/late/variable” based primarily on their time relationship to contractions. These theoretical concepts are like memes (ideas/beliefs). Lessons from “memetics” are that the most popular, attractive or established beliefs may not necessarily be true, scientific, beneficial or even without harm. Decelerations coincident with contractions with trough corresponding to the peak of contractions cannot be explained by cord-compression or increasing hypoxia (from compromised uteroplacental perfusion, cord-compression or even cerebral hypoperfusion/anoxia purportedly conceivable from head-compression). Decelerations due to hypoxemia would be associated with delayed recovery of decelerations (lag phase). It is a scientific imperative to cast away disproven/falsified theories. Practices based on unscientific theories lead to patient harm. Clinicians should urgently adopt the categorization of FHR decelerations based primarily of the time relationship to contractions as originally proposed by Hon and Caldeyro-Barcia. This analytical review shows it to be underpinned by most robust physiological and scientific hypotheses unlike the other categorizations associated with untruthful hypotheses, irreconcilable fallacies and contradictions. Without truthful framework and meaningful pattern-recognition of FHR decelerations, the CTG will not fulfil its true potential.