Characterizing the brain structural adaptations across the motherhood transition

Women that become mothers face notable physiological adaptations during this life-period. Neuroimaging studies of the last decade have provided grounded evidence that women's brains structurally change across the transition into motherhood. The characterization of this brain remodeling is currently in its early years of research. The current article reviews this scientific field by focusing on our longitudinal (pre-to-post pregnancy) Magnetic Resonance Imaging (MRI) studies in first-time parents and other longitudinal and cross-sectional studies of parents. We present the questions that are currently being answered by the parental brain literature and point out those that have not yet been explored. We also highlight potential confounding variables that need to be considered when analyzing and interpreting brain changes observed during motherhood.This work was supported by Ministerio de Ciencia e Innovación project RTI2018-093952-B-100 and by Instituto de Salud Carlos III projects CP16/00096 and PI17/00064, and co-funded by European Regional Development Fund (ERDF), A way to make Europe. MM-G was funded by Ministerio de Ciencia e Innovación, Instituto de Salud Carlos III, Predoctorales de Formación en Investigación en Salud (PFIS) (contract FI18/00255) and a predoctoral Fulbright grant. SC was funded by a Miguel Servet Type I research contract (CP16/00096). MM-G and SC were co-funded by European Social Fund Investing in your future. The project leading to these results has received funding from la Caixa Foundation under the project code LCF/PR/HR19/52160001, from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No 883069), and from the Centro Nacional de Investigaciones Cardiovasculares (CNIC). The CNIC is supported by Instituto de Salud Carlos III (ISCIII), Ministerio de Ciencia e Innovación and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (SEV-2015-050)

Women's neuroplasticity during gestation, childbirth and postpartum.

Pregnancy is a unique neuroplastic period in adult life. This longitudinal study tracked brain cortical changes during the peripartum period and explored how the type of childbirth affects these changes. We collected neuroanatomic, obstetric and neuropsychological data from 110 first-time mothers during late pregnancy and early postpartum, as well as from 34 nulliparous women evaluated at similar time points. During late pregnancy, mothers showed lower cortical volume than controls across all functional networks. These cortical differences attenuated in the early postpartum session. Default mode and frontoparietal networks showed below-expected volume increases during peripartum, suggesting that their reductions may persist longer. Results also pointed to different cortical trajectories in mothers who delivered by scheduled C-section. The main findings were replicated in an independent sample of 29 mothers and 24 nulliparous women. These data suggest a dynamic trajectory of cortical decreases during pregnancy that attenuates in the postpartum period, at a different rate depending on the brain network and childbirth type.The project leading to these results has received funding from the Instituto de Salud Carlos III (project PI22/01365), Ministerio de Ciencia, Innovación y Universidades (project RTI2018-093952-B-100), ‘la Caixa’ Foundation under project code LCF/PR/HR19/52160001, the European Research Council under the ‘European Union’s Horizon 2020’ research and innovation programme (grant agreement no. 883069) and the Centro Nacional de Investigaciones Cardiovasculares (CNIC), and was co-funded by the European Regional Development Fund (ERDF), ‘A way of making Europe.’ M.M.-G. was funded by Ministerio de Ciencia, Innovación y Universidades, Instituto de Salud Carlos III, Predoctorales de Formación en Investigación en Salud (PFIS) contract (FI18/00255) and a predoctoral Fulbright grant; S.C. was funded by a Miguel Servet Type II research contract (CPII21/00016). M.M.-G. and S.C. were co-funded by the European Social Fund ‘Investing in your future’.S

Feto-maternal microchimerism: Memories from pregnancy

There is a bidirectional transplacental cell trafficking between mother and fetus during pregnancy in placental mammals. The presence and persistence of fetal cells in maternal tissues are known as fetal microchimerism (FMc). FMc has high multilineage potential with a great ability to differentiate and functionally integrate into maternal tissue. FMc has been found in various maternal tissues in animal models and humans. Its permanence in the maternal body up to decades after delivery suggests it might play an essential role in maternal pathophysiology. Studying the presence, localization, and characteristics of FMc in maternal tissues is key to understanding its impact on the woman's body. Here we comprehensively review the existence of FMc in different species and organs and tissues, aiming to better characterize their possible role in human health and disease. We also highlight several methodological considerations that would optimize the detection, quantification, and functional determination of FMc

Do pregnancy-induced brain changes reverse? The brain of a mother six years after parturition

Neuroimaging researchers commonly assume that the brain of a mother is comparable to that of a nulliparous woman. However, pregnancy leads to pronounced gray matter volume reductions in the mother's brain, which have been associated with maternal attachment towards the baby. Beyond two years postpartum, no study has explored whether these brain changes are maintained or instead return to pre-pregnancy levels. The present study tested whether gray matter volume reductions detected in primiparous women are still present six years after parturition. Using data from a unique, prospective neuroimaging study, we compared the gray matter volume of 25 primiparous and 22 nulliparous women across three sessions: before conception (n = 25/22), during the first months of postpartum (n = 25/21), and at six years after parturition (n = 7/5). We found that most of the pregnancy-induced gray matter volume reductions persist six years after parturition (classifying women as having been pregnant or not with 91.67% of total accuracy). We also found that brain changes at six years postpartum are associated with measures of mother-to-infant attachment. These findings open the possibility that pregnancy-induced brain changes are permanent and encourage neuroimaging studies to routinely include pregnancy-related information as a relevant demographic variable.This work was supported by Ministerio de Ciencia, Innovación y Universidades project RTI2018-093952-B-100 and by Instituto de Salud Carlos III projects CP16/00096 and PI17/00064, and co-funded by European Regional Development Fund (ERDF), “A way of making Europe.” The project exAScale ProgramIng models for extreme Data procEssing (ASPIDE) has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 801091. M.M.-G. and S.C. were funded by Ministerio de Ciencia, Innovación y Universidades, Instituto de Salud Carlos III, Predoctorales de Formación en Investigación en Salud (PFIS), contract FI18/00255 and Miguel Servet Type I research contract CP16/00096, respectively) and co-funded by European Social Fund “Investing in your future.” M.P.-D. was supported by Consejería de Educación e Investigación, Comunidad de Madrid, co-funded by European Social Fund “Investing in your future” (PEJD-2018-PRE/BMD-9401). The project leading to these results has received funding from “la Caixa” Foundation under the project code LCF/PR/HR19/52160001. The Centro Nacional de Investigaciones Cardiovasculares (CNIC) is supported by the Ministerio de Ciencia, Innovación y Universidades, and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (SEV-2015-0505)