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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
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Developmental Biology - Stress in Pregnancy

Pregnant Black Americans Suffer Higher Stress

Low choline levels found in Black American women may be causing high stress levels and premature births...

Researchers at the University of Colorado Anschutz Medical Campus find that many pregnant Black Americans have low levels of choline, an essential nutrient which aids prenatal brain development.
Stress caused by institutional racism may play a role.
The study, out now in Schizophrenia Bulletin, also found these low levels of choline are associated with higher levels of the stress hormone cortisol. It's known that higher cortisol induces a mother to hold choline in her liver instead of delivering it to her baby.
"One of the possible causes of higher cortisol and lower choline levels in Black American women is the burden of institutional racism and the chronic subconscious stress that it causes."

Robert Freedman MD, Professor, Psychiatry, CU Anschutz Medical Campus and study lead researcher.

One hundred eighty three pregnant women were surveyed, with 25 self-identified as Black. Choline levels in these 25 women were lower than those in white women living in their same neighborhoods. While Black participants did not indicate more stress, their cortisol levels were markedly higher than normal.

Researchers also examined a group of pregnant Black women living in Uganda. Choline levels obtained from these 166 participants were significantly higher than in Black American women, indicating that high stress rather than ancestry contributes to low choline levels in Black American women.

In a separate clinical trial with 100 pregnant women, 50 (seven of whom were Black) received a phosphatidylcholine supplement to raise their choline levels. Fifty received a placebo (eight of these women were Black). Both groups received instruction on how to increase choline in their diets.

Premature birth was prevented in the seven Black women who received choline supplements — but not prevented in the eight who received the placebo. By age four, children whose mothers received phosphatidylcholine supplement had fewer problems with attention and social behavior.

These two studies combined represent the largest group of Black women studied for the effects of prenatal choline on the outcome of their pregnancy.
"We hope to get the word out, to all women and especially to stressed, pregnant Black women, that taking supplemental choline, in addition to the prenatal vitamins they already take, can significantly improve outcomes for their children."

Robert Freedman, MD.

Black Americans have increased risk for schizophrenia and other mental illnesses with prenatal origins. Prenatal choline promotes infant brain development and behavioral outcomes, but choline has not been specifically assessed in Black Americans. Pregnant women (N = 183, N = 25 Black Americans) enrolled in a study of prenatal stressors and interactions with prenatal choline. Black American women had lower 16-week gestation plasma choline than Whites. Lower choline was not related to obesity, income, or metabolic genotypes. Pregnant women in rural Uganda have higher choline levels than Black American women. Black Americans'lower choline was associated with higher hair cortisol, indicative of higher stress. Lower maternal choline was associated with offsprings'lower gestational age at birth and with decreased auditory P50 inhibition, a marker of inhibitory neuron development. Behavioral development was assessed on the Infant Behavior Questionnaire-R-SF (IBQ-R) at 3 months. Lower Black American maternal gestational choline was associated with lower infant IBQ-R Orienting/Regulation, indicating decreased attention and relation to caregivers. Additional evidence for developmental effects of choline in Black Americans comes from a randomized clinical trial of gestational phosphatidylcholine supplementation versus placebo that included 15 Black Americans. Phosphatidylcholine increased gestational age at birth and newborn P50 inhibition and decreased Social Withdrawn and Attention problems at 40 months of age in Black Americans'offspring compared to placebo. Inhibitory and behavioral deficits associated with lower prenatal choline in offspring of Black American women indicate potential developmental predispositions to later mental illnesses that might be ameliorated by prenatal choline or phosphatidylcholine supplementation.

Sharon K Hunter, M Camille Hoffman, Lizbeth McCarthy, Angelo D'lessandro, Anna Wyrwa, Kathleen Noonan, Uwe Christians, Etheldreda Nakimuli-Mpungu, Steven H Zeisel, Amanda J. Law and Robert Freedman.

The late Randal G. Ross designed and initiated this study. The late Carl Bell encouraged the National and American Medical Associations to advocate for increased choline in prenatal vitamins based on this study. The authors have declared that there are no conflicts of interest in relation to the subject of this study.

National Institute of Child Health and Human Development (K12HD001271-11 to M.C.H.); National Center for Advancing Translational Sciences (UL1 TR001082); National Institute of Diabetes and Digestive and Kidney Diseases (R01DK56350 to S.Z.); The Institute for Children’s Mental Disorders; and The Anschutz Foundation.

Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model

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Nov 25 2020   Fetal Timeline   Maternal Timeline   News

"One of the possible causes of higher cortisol and lower choline levels in Black American women is the burden of institutional racism and the chronic subconscious stress that it causes," Robert Freedman MD, professor of psychiatry, CU Anschutz Medical Campus.

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