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Pregnancy Timeline by SemestersDevelopmental TimelineFertilizationFirst TrimesterSecond TrimesterThird TrimesterFirst Thin Layer of Skin AppearsEnd of Embryonic PeriodEnd of Embryonic PeriodFemale Reproductive SystemBeginning Cerebral HemispheresA Four Chambered HeartFirst Detectable Brain WavesThe Appearance of SomitesBasic Brain Structure in PlaceHeartbeat can be detectedHeartbeat can be detectedFinger and toe prints appearFinger and toe prints appearFetal sexual organs visibleBrown fat surrounds lymphatic systemBone marrow starts making blood cellsBone marrow starts making blood cellsInner Ear Bones HardenSensory brain waves begin to activateSensory brain waves begin to activateFetal liver is producing blood cellsBrain convolutions beginBrain convolutions beginImmune system beginningWhite fat begins to be madeHead may position into pelvisWhite fat begins to be madePeriod of rapid brain growthFull TermHead may position into pelvisImmune system beginningLungs begin to produce surfactant
CLICK ON weeks 0 - 40 and follow along every 2 weeks of fetal development

Developmental Biology - Telomeres

Relax Through Your Pregnancy

A mother's ability to manage stress has beneficial affects to both her and her newborn...

Research from Charité - Universitätsmediz in Berlin reveals that a mom's psychological well being during pregnancy has a positive effect not only on her health - but her newborn child as well.

Increased infant telomere length suggests a mother's positive phychological state reduces the rate of cell aging in her infant, and could have an effect on her child's future health. Results from this study have been published in the American Journal of Psychiatry.

A variety of pregnancy-related factors can impact child development. Until now, researchers had primarily focused on the negative effects of stress, excess weight and poor nutrition — and how these might affect placental function, premature birth and children's general health. At the cellular level, various pregnancy-related factors can have a direct impact on 'telomeres', cellular structures that protect the ends of chromosomes during cell division and can be lengthened by the enzyme telomerase.
Telomere length is a molecular marker of cell aging. Linked to life expectancy and a range of age-related disorders, the effects of maternal stress have been widely studied, data on protective maternal factors and their positive effects on child development remain limited.

Researchers, led by Sonja Entringer PhD, proffessor of Charité's Institute of Medical Psychology, have shown that a mother's ability to cope with stress during pregnancy - her 'psychological resilience' - is linked to telomere length. The more positive a mother's attitude during pregnancy, the longer her children's telomeres. Entringer was awarded a European Research Council 'Starting Grant' in 2016, which enabled her to develop her research.

"Positive maternal psychological characteristics are biologically embedded and have a protective effect on the fetus," explains Proffessor Entringer. In a previous study, researchers had examined the way maternal stress in pregnancy affected telomere length in their offspring.
The current study, which saw Prof. Entringer's team work with Nobel Laureate Elizabeth Blackburn of the University of California along with colleagues in Finland, also gave them access to a large study population made up of 650 mother and child pairs. Telomere length was determined at birth, using cells from cord blood.

Positive attitude in the face of stress was determined using a 'resilience index', took into account the pregnant women's psychological wellbeing and perceived social support.
"This study underlines the importance of maternal psychological well being during pregnancy in the developmental programming of lifelong health and disease; and, the significance of improved psychosocial support during pregnancy."

Sonja Entringer PhD, Associate Professor, University of California, San Francisco, California, USA.

Objective: In the context of the importance of elucidating the determinants of the initial, newborn setting of telomere length (TL), it is increasingly evident that maternal stress and stress-related processes during pregnancy play a major role. Although psychological resilience may function as a buffer, research in this area has not yet examined its potential role vis-à-vis that of stress. The authors examined the relationship between maternal psychological resilience during pregnancy and newborn TL.

Methods: In a sample of 656 mother-child dyads from the Prediction and Prevention of Preeclampsia and Intrauterine Growth Restriction cohort, multiple serial assessments were conducted over the course of pregnancy to quantify maternal stress, negative and positive emotional responses to pregnancy events, positive affect, and perceived social support. Principal component analysis identified two latent factors: stress and positivity. A measure of resilience was computed by regressing the positivity factor on the stress factor, in order to quantify positivity after accounting for stress. TL was measured using quantitative polymerase chain reaction in leukocytes extracted from cord blood shortly after birth. Linear regression was used to predict newborn TL from maternal resilience during pregnancy, adjusting for other potential determinants.

Results: Maternal stress significantly predicted shorter newborn TL (ß=-0.079), and positivity significantly predicted longer TL (ß=0.135). Maternal resilience (positivity accounting for stress) was significantly and positively associated with newborn TL (ß=0.114, 95% CI=0.035, 0.189), with each standard deviation increase in resilience predicting 12% longer newborn TL.

Conclusions: The results indicate that maternal psychological resilience may exert a salubrious effect on offspring telomere biology and highlight the importance of enhancing maternal mental health and well-being during pregnancy.

Glenn Verner MPH, Elissa Epel PhD, Marius Lahti-Pulkkinen PhD, Eero Kajantie MD, PhD, Claudia Buss PhD, Jue Lin PhD, Elizabeth Blackburn PhD, Katri Räikkönen PhD, Pathik D. Wadhwa MD, PhD and Sonja Entringer PhD.

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Sep 14 2020   Fetal Timeline   Maternal Timeline   News

CREDIT Australian Academy of Science.

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