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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 - Advanced Age Pregnancy

Late Pregnancy Risks Heart In Moms and Sons

Study shows blood vessel function declines with advanced age putting mom and her male offspring at risk...

New research published in The Journal of Physiology demonstrates that adult offspring born to older mothers are more susceptible to heart risks in later life. These results could be crucial in developing preventative treatments for children born to older women.
Delaying pregnancy may increase the risk of cardiovascular disease in both women and their children, with boys at higher risk of disease, according to a new study.

Researchers from the University of Alberta in Canada will present their findings today at the American Physiological Society's (APS) Cardiovascular, Renal and Metabolic Diseases: Sex-Specific Implications for Physiology conference in Knoxville, Tenn.

Previous studies have found that advanced maternal age - 35 or older during pregnancy - increases the risk of impaired blood vessel function and reduced blood flow to the placenta. These issues endanger the growth and overall health of the unborn child and may contribute to heart disease later in the pregnant woman's life. Researchers grouped a rat model of advanced maternal age according to pregnancy status described as "never pregnant," "postpartum" and "pregnancy loss."

A rat heart shows volume of blood in non-pregnant (Left) and pregnant (Right) animal.
Human pregnancy increases blood volume by 40% on average.

Researchers found the pregnancy loss group had less widening of their blood vessels (vasodilation) compared to groups that were never pregnant or had recently delivered. In some cases, less vasodilation led to decreased vascular health. Also, the postpartum group had reduced vasodilation in arteries of the intestines. According to researchers: "The data demonstrates mechanisms which may lead to worsened outcomes at an advanced maternal age, including early pregnancy termination, and later life cardiovascular dysfunction."

Researchers also found sex-specific differences in health risks of older rats' offspring. Males born to the postpartum group had impaired function of the blood vessel lining and cardiac risk factors associated with interrupted blood flow, female offspring did not.
"Given the increasing trend toward delaying pregnancy, our findings have significant population and health care implications and further illustrate pregnancy as a window of opportunity to assess cardiovascular health."

Key points
Advanced maternal age increases the risk of pregnancy complications such as fetal growth restriction, hypertension and premature birth.
Offspring born from compromised pregnancies are at increased risk of cardiovascular disease as adults. However, the effect of advanced maternal age on later-onset disease in offspring has not been investigated.
In adulthood, male but not female offspring born to dams of advanced maternal age showed impaired recovery from cardiac ischaemia/reperfusion injury.
Endothelium-dependent relaxation was also impaired in male but not female offspring born from aged dams.
Oxidative stress may play a role in the developmental programming of cardiovascular disease in this model.
Given the increasing trend toward delayed parenthood, these findings have significant population and health care implications and warrant further investigation.

Exposure to prenatal stressors, including hypoxia, micro- and macronutrient deficiency, and maternal stress, increases the risk of cardiovascular disease in adulthood. It is unclear whether being born from a mother of advanced maternal age (>=35 years old) may also constitute a prenatal stress with cardiovascular consequences in adulthood. We previously demonstrated growth restriction in fetuses from a rat model of advanced maternal age, suggesting exposure to a compromised in utero environment. Thus, we hypothesized that male and female offspring from aged dams would exhibit impaired cardiovascular function as adults. In 4-month-old offspring, we observed impaired endothelium-dependent relaxation in male (P < 0.05) but not female offspring born from aged dams. The anti-oxidant polyethylene glycol superoxide dismutase improved relaxation only in arteries from male offspring of aged dams (?Emax: young dam 1.63 0.80 vs. aged dam 11.75 4.23, P < 0.05). Furthermore, endothelium-derived hyperpolarization-dependent relaxation was reduced in male but not female offspring of aged dams (P < 0.05). Interestingly, there was a significant increase in nitric oxide contribution to relaxation in females born from aged dams (?Emax: young dam 24.8 12.1 vs. aged dam 68.7 7.7, P < 0.05), which was not observed in males. Recovery of cardiac function following an ischaemia-reperfusion insult in male offspring born from aged dams was reduced by ~57% (P < 0.001), an effect that was not evident in female offspring. These data indicate that offspring born from aged dams have an altered cardiovascular risk profile that is sex-specific. Given the increasing trend toward delaying pregnancy, these findings may have significant population and health care implications and warrant further investigation.

Christy-Lynn M. Cooke, Amin Shah, Raven D. Kirschenman, Anita L. Quon, Jude S. Morton, Alison S. Care, Sandra T. Davidge.

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Oct 4, 2018   Fetal Timeline   Maternal Timeline   News   News Archive

Judith Lederman became pregnant with twins during her second marriage - and at age 53!
Twins always increase pregnancy to "high risk" - but so does a mother's age over 35.
Judith's twin sons are thriving, as is she. Pregnant At 53.

Phospholid by Wikipedia