The Birthing Brain: A Lacuna in Neuroscience

The Birthing Brain: A Lacuna in Neuroscience Orli Dahan Tel-Hai College, Upper Galilee, 12208 Israel orlydah@telhai.ac.il https://orcid.org/0000-0002-7649-3361 This paper is not the copy of record and may not exactly replicate the final, authoritative version of the article. The final article is available in Brain & Cognition, June 2021, 105722: https://doi.org/10.1016/j.bandc.2021.105722 Share Link: https://authors.elsevier.com/a/1coKp-HGGhTBh Abstract During pregnancy, maternal brain neuroplasticity indicates vast neurofunctional and neuroanatomical changes. Recent findings documented a similarly massive readjustment after pregnancy. Currently, these brain changes are interpreted as preparation for and adjustment of the maternal brain to motherhood. Yet, this perspective leaves many questions unsolved. Neuroscientific studies have not yet been conducted to determine the brain areas that function during natural childbirth even though physiological birth is the natural process of women who have reproduced successfully throughout two million years of evolution of the genus Homo. It is rational to believe that the female brain is an active and crucial actor during birth and that birth, itself, is a process that requires brain neuroplasticity. Lack of studies of the birthing brain and brain preparation for birth is a significant lacuna in neuroscience research. I demonstrate theoretically that a new hypothesis for complementary interpretation of maternal brain neuroplasticity is reasonable: Certain maternal brain changes during pregnancy can be interpreted as brain preparation for birth and certain maternal brain changes after birth can be interpreted as brain recovery after the tremendous event of birth. This essay can be a starting point for new directions in neuroscience studies. Keywords birthing consciousness; birthing brain; evolutionary psychology; childbirth; maternal brain neuroplasticity 1 Highlights - During pregnancy, maternal brain neuroplasticity is extensive. - This neuroplasticity is currently interpreted as preparation for motherhood. - Brain preparation for delivery is an overlooked area of research in neuroscience. - A lacuna exists in neuroscience regarding neurofunctional processes during birth. - Some brain changes in pregnancy are likely preparation for birth not motherhood. 1. Childbirth and the birthing brain: an overlooked research area During pregnancy, the maternal brain undergoes a sequence of adaptive biochemical changes that are fundamental for supporting fetal growth and development: protecting both mother and fetus from stress reactions, preparing the neuroendocrine circuits that drive the birth process, and stimulating the mammary glands to produce milk (Voltolini & Petraglia, 2014). Neuroplasticity of the brain during childbirth, in contrast, has not been studied for adaptive biochemical changes. Recently, Kenrick posited that in order to generate an interesting and fruitful hypothesis for such big questions in evolutionary psychology, one is to ask whether an existing phenomenon has been fully explained at other levels of analysis: "Pick a well-established phenomenon (such as women's preferences for muscular men…) and ask what we don't know about how it is represented in the brain." (Kenrick, 2020, 4). In the spirit of that guidance, preliminary to asking how childbirth is represented in the brain, it is important to delineate what has been established to date. First, birth is not simply a mechanical process related to the pelvic anatomy of the birthing woman and size of the fetal head. There are essential neuro-biochemical changes induced during childbirth (Terzidou, 2007; Voltolini & Petraglia, 2014). These neuro-biochemical features are hypersensitive to environmental aspects and they can impede the birth process (Dahan, 2021b; Hishikawa et al., 2019). Second, the rates of obstetric interventions are rising throughout the western world, together with the rates of postpartum PTSD (Dekel et al., 2017) and other mental health complications after childbirth (Dekel et al., 2019). Additionally, there are correlations between highly interventional births and PP-PSTD (Thiel & Dekel, 2020). Lastly, women who are not unique from a morphological perspective can give birth easily and quickly; whereas others need medical intervention after days of hard labor (Odent, 2019). Thus, it is reasonable to believe that birthing is significantly related to brain processes and not simply a mechanical process of the body. Beyond biochemical and endocrinological factors, the birthing brain mechanism remains an enigma. It is unknown whether there exists a specific brain mechanism for natural birth or what happens in the brain when the natural process of birth is interrupted. Advances have been made, however, in understanding the states of consciousness of women during physiological-undisturbed 2 birth (Dahan, 2020), as well as in how women experience and react during birth dystocia (Kissler et al., 2019). Although the answer to the big question 'what is consciousness?' remains elusive, perhaps, (Koch, 2018), it is clear that mental states correlate with brain states. Thus, many recognize consciousness science as an indispensable area of biomedical research (Michel et al., 2019). But surprisingly, there is no research on the brain areas active during natural birth – what appears to be an obvious correlation between brain functioning and women who have managed to successfully reproduce throughout over two million years of evolution of the genus Homo. There are solid evolutionary reasons to believe that birth, itself, is a process requiring brain preparation: In evolutionary times, without the help of modern medicine and obstetric professionals, women who did not succeed at birthing naturally did not survive (Dahan, 2020). Women also needed to be in relatively good health after delivery to take care of their newborn; babies without mothers had a lower chance of survival (Atrash, 2011). As noted, studies have examined maternal brain functioning during and after pregnancy but not during the birth process, be it a physiological or highly medical birth. Some may claim that this void is not a lacuna for it is simply too difficult to examine. However, this claim is easily disputed as studies have been conducted on the functioning of a woman's brain during orgasm (Jannini et al., 2018; Wise et al., 2017). Additionally, three-dimensional (3D) magnetic resonance imaging (MRI) was used recently to show how the fetal head molds and brain shape changes during birth (Ami et al., 2019). These studies demonstrate current technological capabilities notwithstanding the challenges of conducting the examinations. I offer here a new and complementary perspective to the lacuna in the study of the birthing brain. I will discuss the broadly accepted view that nearly all of the maternal brain changes during pregnancy occur to prepare the brain for motherhood. Perhaps this is why neuroscience focuses on studying the maternal brain before birth and after birth, thus skipping over the event of childbirth itself. Then, a new hypothesis will be suggested for complementary interpretation of the current data on women's brains before birth and postpartum: Some of the maternal brain changes during pregnancy can be interpreted as preparation of the brain for birth, while some of the maternal brain changes postpartum can be interpreted as brain recovery after the tremendous event of birth. Testing this hypothesis empirically will first require obviating the lacuna i.e., demonstrating the brain mechanisms during different birth processes. The brain mechanism during physiological birth should be compared to that of highly interventionist medical births and planned and emergency c-section birth. If the new hypothesis is confirmed, the implications can be significantly beneficial to birthing mothers and their infants, impacting the science of delivery and public health. 3 2. Maternal brain neuroplasticity: Currently interpreted as brain preparation for motherhood Numerous studies of maternal brain neuroplasticity indicate tremendous neurofunctional and neuroanatomical changes during pregnancy (Almanza-Sepúlveda et al., 2018; Farrar et al., 2014; Hoekzema et al., 2017; Lübke et al., 2017; Macbeth & Luine, 2010; Roos et al., 2011) and after birth (Barba-Müller et al., 2019; Hoekzema et al., 2020; Kim et al., 2016), including massive readjustment of the macro-structure of the maternal brain (Luders, 2020). Scholars interpret these changes as adaptations that benefit the phases of pregnancy, such as protection and development of the fetus (Voltolini & Petraglia, 2014), maternal behavior and caregiving postpartum (Hoekzema et al., 2017; Hoekzema et al., 2020; Pereira, 2016), lactation (Grattan, 2011; Salais-López et al., 2017), and even post lactation (Pawluski et al., 2016). Specifically, Luders et al. (2020) explain the massive readjustment and increase of gray matter after giving birth in terms of adapting neurofunctionality both to enable the multifaceted repertoire of complex behaviors associated with being a mother and to replace tissue lost during pregnancy. However, a postpartum gray matter increase related to motherhood does not explain the significant decreases in brain size, tissue volume, and various cortical measures such as thickness, surface area, and gyrification during pregnancy. Additional neuroanatomical and phenomenological questions remain unsolved. Hence, research is necessary to map the specific timing of these neuroanatomical adjustments and the potential factors driving these alterations across the peripartum period, for the precise mechanism and physiologic importance of the decrease in gray matter during pregnancy and subsequent increase after delivery are unknown (Cárdenas et al., 2020; Oatridge et al., 2002). However, none of the studies noted interpret the changes as benefitting the episode of childbirth. The evolutionary significance of the emergence of nurturing and caring responses in mammals is well accepted. Lambert and Kinsley (2012) analyzed the neurobiological modifications that maintain maternal responses in both rodent models and humans and reported dramatic neurobiological changes accompanying the onset of motherhood. They concluded that the maternal brain is a striking example of the adaptation necessary for various aspects of mammalian survival but made no mention of the brain and behavioral modifications that accompany the onset and the course of birth. Although it is accepted that once pregnant, many adaptations – such as emotional regulation and enhanced social attentiveness – must occur to prepare the mammalian mother to respond appropriately to her impending delivery (Lambert, 2012), all studies refer only to adaptation to motherhood, neglecting the crucial event of childbirth itself (Odent, 2019). This neglect is despite the broad understanding that the adaptive brain alterations occur to promote the survival, care, and protection of the most expensive mammalian metabolic and genetic investment (Kinsley & Meyer, 4 2010). Ignoring the event of childbirth might reflect an underlying assumption that there are no crucial brain alterations occurring during delivery or, minimally, according to current neuroscience literature, the brain is not preparing for the event of childbirth, only for what follows. 3. A new hypothesis: brain preparation for childbirth as a complementary interpretation for maternal brain neuroplasticity Something singular happens during natural and undisturbed birth, at least phenomenologically. I recently coined the term “birthing consciousness” to refer to the special psycho-physical altered state of consciousness of women during unmedicated birth. Birthing consciousness is a state of focus and retreat characterized by changes in focused attention, time distortion, disinhibition from social constraints, and pain reduction, accompanied by increased feelings of floating, calm, and peacefulness (Dahan, 2020, 2021a, 2021b). Many of these features correspond with the transient hypofrontality brain mechanism, which involves the progressive downregulation of brain networks supporting the highest cognitive capacities. This downregulation follows a functional hierarchy, one phenomenological subtraction at a time, to those supporting more basic functions (Dietrich & Al-Shawaf, 2018). Thus, I suggest that birthing consciousness can be an example of an adaptive altered state of consciousness associated with transient hypofrontality: Since successful natural birth for the mother and her baby was essential to reproduction throughout most of human history, and since natural birth is an experience of extreme pain and the transient hypofrontality brain mechanism correlates with pain reduction (among other phenomenological and cognitive features that ameliorate birthing), ‘birthing consciousness' increases the probability for optimal birth outcomes (Dahan, 2020, 2021a, 2021b). The few neurological studies of the maternal brain during the specific episode of childbirth appear to support the suggestion that birthing consciousness is a beneficial adaptive state. The acute event of birth requires physiological preparation. Thus, Odent (2019) hypothesizes that in late pregnancy, maternal physiological modifications occur that prepare the pregnant woman for the significant event of the birth itself and not only for motherhood. I believe that this hypothesis is consistent with Macbeth and Luine's (2010) research on rodents indicating that pregnancy is a factor causing changes in neural function and behaviors that are not directly maternal in nature, but involve cognition, affect, and responses to stress. Thus, female rats that experienced pregnancy generally demonstrated greater resilience to stress, decreased anxiety, and better memory than female rats that had not experienced pregnancy and motherhood. Barba-Müller et al. (2019) analyzed studies of the changes in brain structure and function that a woman undergoes during pregnancy and the postpartum period. Their findings suggest evidence that 5 birthing consciousness involves the transient hypofrontality brain mechanism. Hoekzema et al. (2017) reported that first-time mothers undergo a symmetrical pattern of extensive gray matter volume reductions throughout and immediately following pregnancy. Specifically, the grey matter volume reductions immediately after pregnancy were primarily located in the anterior and posterior midline (medial frontal cortex/anterior cingulate cortex and precuneus/posterior cingulate cortex), the bilateral lateral prefrontal cortex (primarily the inferior frontal gyri), and the bilateral temporal cortex (the superior temporal sulci extending to surrounding lateral temporal as well as medial temporal sections). Barba-Müller et al. (2019) found indications that brain structure begins to develop postpartum. Using brain imaging (MRI) data, Kim et al. (2010) assessed morphological changes in the mother’s brain during the postpartum period. From 2–4 weeks postpartum to 3–4 months postpartum, mothers demonstrated increases in gray matter volume in sections of the parietal lobe, prefrontal cortex, and midbrain. In contrast to the observed structural brain changes across pregnancy, no gray matter decreases were detected in the early postpartum period. Barba-Müller et al. (2019) conclude that although it is difficult to compare these findings due to differences in study parameters (e.g., time period between scans, statistical thresholds, the number of participants, and morphometric procedures), the findings suggest that pregnancy and motherhood exert diverging and even opposing effects on sections of a woman’s brain in terms of gray matter volume change. Interestingly, Barba-Müller et al. (2019) analyze these findings in terms of pregnancy and motherhood, omitting the crucial connecting event – the birth itself. These findings may indicate that during pregnancy and before birth there is a reduction in gray matter volume primarily affecting the anterior and posterior cortical midline and specific sections of the bilateral lateral prefrontal and temporal cortex; after birth, there is an increase in gray matter volume in sections of the parietal lobe, prefrontal cortex, and midbrain. These changes may be connected with brain preparation for birth and may also indicate stimulation and occurrence of transient hypofrontality. The occurrence of transient hypofrontality is also supported by Hoekzema et al.’s (2017) observation that the volume reductions were not distributed randomly across the brain, but located primarily in the cerebral cortex. Using fMRI studies, Kim et al. (2016) also examined the neuroplasticity of human mothers’ brains and found differences in relation to birthing methods: Physiological birth triggered critical sensory stimulation that increased the release of oxytocin, whereas such sensory stimulation was absent in cesarean delivery. Thus, Kim et al. (2016) proposed a model for maternal brain function based on task-based imaging studies, highlighting brain processes that are mechanistically related to certain cortico-limbic circuits. During the first month postpartum, mothers from the vaginal delivery group exhibited greater neural responses to their own babies’ cries compared to mothers who delivered by cesarean section. Vaginal delivery, compared to cesarean section, was associated with greater responses in brain areas linked to motivation (striatum, hypothalamus, amygdala), sensory information processing (the superior and middle temporal gyri, fusiform gyrus, and thalamus), and 6 cognitive and emotional control (superior frontal gyrus). Interestingly, further neuroplasticity among healthy mothers was exhibited by the disappearance of significant functional difference between vaginal and cesarean delivery in response to baby-cry by three to four months postpartum. The findings of Kim et al. (2016) support my hypothesis that the birthing process correlates with a specific brain mechanism: that something crucial occurs when a woman gives birth physiologically that does not occur during medicated births. Further support for birthing consciousness as a case of transient hypofrontality is evidenced by Roos et al. (2011), who reported altered prefrontal cortex function in pregnant women (compared with women in the control group) during the processing of fear-relevant stimuli. They suggest that the underlying neuroanatomical basis for cognitive-affective alterations during pregnancy may include frontal-amygdala circuitry. Roos et al. (2011) used Near-infrared spectroscopy (NIRS), a safe method for assessing neural circuitry during pregnancy. NIRS detects real-time upper cortical vascular responses to neural activation by infrared spectrum light transmitted through diodes placed on the scalp. The particularly relevant finding concerning birthing consciousness is the fact that prefrontal cortex activation to fearful faces was significantly higher during trimester 2 than during trimester 3 of pregnancy. A related study of Lübke et al. (2017) reported a decreasing and altering response to chemosensory anxiety signals over the course of pregnancy. In contrast to non-pregnant women, enhanced or accelerated evaluative (P3-2 amplitude, P3-2 latency) processing of the chemosensory alarm signal was strikingly absent in pregnant women. Pregnant women even recorded a delay in the EEG correlate of evaluative responses (P3-2 latencies) to anxiety sweat in direct comparison to nonpregnant women. In line with altered attentional processing, non-pregnant women reported a significantly higher number of odors perceived during EEG recording than pregnant women, with women early in pregnancy having reported higher numbers than women in late pregnancy. Moreover, current source density analyses further revealed that the attenuated processing of the chemosensory signals was not only progressive over the course of pregnancy, but also showed qualitative changes: Women in the first trimester still showed neuronal responses to anxiety sweat within the P3-1 and P32 latency ranges, but with an atypical spatial distribution indicating a cortical dysregulation. Women in the third trimester of pregnancy did not show any detectable neuronal sources during late processing when presented with anxiety sweat. Thus, the decoding of the alarm signal’s psychobiological relevance, together with its automatic attention-capturing features, is quantitatively and qualitatively altered in early vs. late pregnancy (Lübke et al., 2017, p. 8). Roos et al. (2011) argue that the increased attention to fearful faces during pregnancy is consistent with the evolutionary premise that increased responsiveness to threat during pregnancy may be adaptive, resulting in greater protection by mothers of themselves and their unborn children. 7 However, if this premise is sound, the decrease in responsiveness to threat in the third trimester just prior to birth requires elucidation. The explanation of adaptation offered by Lübke et al. (2017) for the findings of cortical dysregulation is in line with Roos et al. (2011): A decreasing and altering processing of chemosensory anxiety signals during pregnancy probably reflect a basic mechanism protecting the unborn infant against maternal stress deriving from automatic emotional contagion. Such altered responsiveness most probably reflects an evolutionary conserved mechanism protecting pregnant women and their offspring from adverse effects of automatic anxiety contagion via chemical signals that are otherwise ubiquitously functional in humans and across phyla. While this explanation seems sound, another is possible, stemming from brain mechanisms triggered in preparation for birth. Changes in hormone levels can stimulate changes in prefrontal cortex functions which, in turn, stimulate changes in cognitive-affective processing and anxiety (Roos et al., 2011). During birth, stress, fear, and anxiety are predictors for negative consequences, including maximum pain during labor, dystocia, and emergency cesarean section (Leap et al., 2010). Hence, it is possible that the brain prepares for birthing during pregnancy by decreasing the processing of chemosensory anxiety signals, for these signals have the potential to disturb the physiological process of birth. It is also possible that, in the third trimester, increased responsiveness to threat may hinder the very onset of the physiological process of birth, explaining why increased responsiveness to threat is higher in the second trimester than the third. Given the critical advantage for ensuring a successful outcome of physiological birth, the new hypothesis, that this evidence of neuroplasticity may indicate preparation of the brain for birthing, provides a complementary explanation for these important research findings. An earlier study is worthy of reference here. Brunton and Russell (2008) reviewed the changes in the maternal brain from the accepted viewpoint of adapting for motherhood. After birth, there is a rapid expression of maternal behavior stemming from prolonged exposure to pregnancy levels of estrogen, prolactin/placental lactogen, and progesterone, followed by progesterone withdrawal. However, repeated exposure to young over several days induced maternal behavior in virgin rats (Brunton & Russell, 2008). These findings question whether the explanation of brain preparation for motherhood is comprehensive. If a mere few days of exposure to babies produces maternal reactions, then perhaps the expectant brain is not only adapting for motherhood, but also for the crucial stage of birth. For if birth fails, the stage of motherhood never arrives. Describing their innovative study of fetal head molding and brain shape changes during the second stage of delivery, Ami et al. (2019) wrote, "Factors related to a safe vaginal delivery include an adequately sized and shaped maternal bony pelvis, soft tissue shaping of the birth canal during delivery, sufficient uterine contractions, and a fetal head of the proper size and ability to mold… Labor dystocia most often results from a combination of these fetal and maternal factors" (2019, p. 8 2). This view is, however, partial: The ability to birth physiologically is not only a function of the above factors, but also, and perhaps primarily, a function of the brain of the birthing mother. Sufficient physiological uterine contractions necessary for birth result from hormonal orchestration in the birthing woman's brain (Lothian, 2014). Understanding labor and birth requires integrating knowledge of the state of consciousness, environment, and behavior of the birthing woman (Dahan, 2020; Dixon et al., 2013). Birthing women are not just bodies that happen to give birth, but complex subjects. Together with the size and shape of their pelvises, their birthing brains are also the products of over two million years of evolution. According to current empirical findings, the psycho-physical state of a woman during natural and unmedicated birth is highly fragile and easily interrupted. Triggers of interruptions to birthing consciousness include psychological, physiological, and environmental aspects. Wrønding et al. (2019) found that alteration of lights in the delivery room could influence labor progression and outcome: Delivery rooms with low irradiance and calming lights correlate with a substantial decrease in cesarean deliveries and the use of synthetic oxytocin infusions. Furthermore, lack of mental support during childbirth or an upset birth environment were correlated with more medicated births (Wrønding et al., 2019). Higher levels of epinephrine, related to fear, anxiety, or anger, were found to be associated with lower uterine contractile activity in the first stage of labor; thus, stress hormones can delay or stop birth. The researchers suggest that this hormonal response is an adaptation: In evolutionary times, the sense of danger and insecurity would stop birth until the threat passed (Hishikawa et al., 2019). Interestingly, the significant cognitive changes that occur during pregnancy include changes affecting memory, which might be related to the evolutionary and adaptive need of the birthing woman to prevent memories from disturbing birth. Almanza-Sepúlveda et al. (2018) examined cortical electroencephalographic correlations (rEEG) during performance of working memory tasks in each trimester of pregnancy. Although the neural system responsible for working memory is known to involve a large number of brain regions, evidence from neurophysiological and lesion studies indicates that the prefrontal cortex is key. In particular, the dorsolateral region and its functional connections with the posterior parietal cortex are primary in relation to both verbal and visuospatial working memory processes. Almanza-Sepúlveda et al. (2018) found that although pregnancy had only a subtle effect on the visuospatial working memory task, different patterns of cortical synchronization were found in each trimester of pregnancy. They maintain that these patterns could represent adaptive mechanisms enabling the pregnant women to focus their attention and activate the additional cognitive resources necessary to solve the working memory tasks adequately. Thus, it has been suggested that working memory is affected during gestation as a result of functional changes in cortical areas such as the prefrontal and parietal cortices. Glynn (2010), using assessments of memory performance and blood samples of 254 women 9 (pregnant and non-pregnant), reported that verbal recall memory - but not recognition or working memory - diminished during human pregnancy and that these decrements persisted after parturition. Raz (2014), using scalp-recorded Event-Related Potentials (ERPs), reported that women in late pregnancy displayed diminished and delayed processing of angry facial expressions, which is in line with reduced attentional capacities. Interpreting these findings in the context of brain preparation for undisturbed birth is consistent with the fact that in rats, mice, and humans, the responsiveness of the HPA axis to a wide range of physical and psychological stressors is also markedly reduced or even abolished in late pregnancy (Brunton & Russell, 2008). In summary, during pregnancy and after birth, many neurofunctional and neuroanatomical changes occur in the maternal brain. Keeping in mind the unique experience of birthing consciousness and its resemblance to the brain mechanism of hypofrontality, it seems reasonable to assume that at least some changes in the maternal brain during pregnancy are intended for preparation for birthing and not only for motherhood, as is commonly presented in current neuroscientific literature. Empirical findings of the cognitive and physiological changes during pregnancy appear to support hypofrontality during the preparation of the maternal brain for the birthing process. 4. Remedying the lacuna: positive systemic implications Remedying the lacuna in research of the birthing brain can lead to significant economic and health benefits. The cost of medicalization of the birth process in the industrial world is high (Tracy & Tracy, 2003). There are also serious physical and mental health costs to women in postpartum resulting from instrumental deliveries and unplanned c-sections (Thiel & Dekel, 2020), and the negative implications for the baby of unnecessarily medicated birth go far beyond the perinatal period (Peters et al., 2018). Therefore, reducing the unscheduled cesarean rate and unnecessary interventional birth is a public health priority (World Health Organization, 2018). Both the Society of Obstetricians and Gynecologists of Canada (SOGC) and the American College of Obstetricians and Gynecologists (ACOG) recently updated their CPGs surrounding labor management, advocating for practices in accordance with physiologic birth unaltered by medical interventions, including epidural (Dufour et al., 2018). Neuroscience studies comparing the brain mechanism of the natural birthing process versus highly medicated interventional birth, emergency c-section, and planned c-section may explain why, despite many efforts, rates of highly medicated births and c-sections are still rising (Zwier, 2020). “Birth is unpredictable” is a well-known idiom, and its implication that women should remain open-minded with realistic expectations regarding their birth preferences is widely accepted (McKenzie-McHarg et al., 2015). However, the unpredictability of the birth process and its potential for sudden complication and emergency intervention should not give sway to determinism. This is not 10 the way science usually works; science typically seeks to increase understanding and thus minimize unpredictability. Greater understanding of the brain mechanism of the natural birth process can lead to decreasing its disruption and maximizing its efficiency. Many can gain from such information: science in general, childbirth educators, midwifery experts, obstetrics professionals, and birthing women and their families – which accounts for nearly every single human being on earth. 5. Conclusion Cognitive and phenomenological empirical research teaches that something extremely significant occurs to the birthing woman during physiological birth. Moreover, births involving obstetrical intervention have tremendous and long-lasting mental and physiological consequences on mothers and their babies. Thus, it is reasonable to assume that delivery is also a function of brain process, and not merely a mechanical process reliant upon size and shape of the maternal pelvis and fetal head. It is also reasonable, from an evolutionary point of view, to state that the brain is a significant participant in the complex event of birth – which is a go-no-go point for the success of reproduction. Throughout most of human evolution, all efforts invested in finding the right pairing, mating, and undergoing a full and healthy pregnancy would have been for naught if the woman was unable to birth. Believing that the brain – crucial to preconception, pregnancy, and postpartum processes – does not prepare a woman for the extremely dangerous and complicated occasion of birth itself does not stand to reason. I have offered a new hypothesis: to interpret the empirical findings concerning maternal brain morphological plasticity before and after birth as preparation of the brain for birth, not only for motherhood. This perspective is new because it connects existing data to the state of consciousness of the birthing woman, predicting the birthing brain mechanism that correlates with these phenomenological and cognitive features. This innovative hypothesis currently cannot be empirically validated because there is a lacuna in neuroscience: No direct research has been conducted, to date, on the specific neurophysiological states of women during natural and undisturbed birth, nor any other kind of birth. Remedying this lacuna can have far-reaching positive implications for the entire midwifery field, as well as for the physiological and mental health of women and their families. References Almanza-Sepúlveda, M. L., Hernández-González, M., Hevia-Orozco, J. C., Amezcua-Gutiérrez, C., & Guevara, M. A. (2018). Verbal and visuospatial working memory during pregnancy: EEG correlation between the prefrontal and parietal cortices. Neurobiology of Learning and Memory, 148, 1-7. 11 Ami, O., Maran, J. C., Gabor, P., Whitacre, E. B., Musset, D., Dubray, C., ... & Boyer, L. (2019). Three-dimensional magnetic resonance imaging of fetal head molding and brain shape changes during the second stage of labor. 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