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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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Fathers' age and lifestyle linked to birth defects

A growing body of research reveals an association between a father's age and alcohol use, and birth defects in his children. Georgetown University Medical Center researchers believe these epigenetic alterations can potentially affect multiple generations.

Study senior investigator, Joanna Kitlinska PhD, an associate professor in biochemistry and molecular and cellular biology, published in the American Journal of Stem Cells, that both parents contribute to the health status of their offspring — a common sense conclusion which science is only now beginning to demonstrate.

"We know the nutritional, hormonal and psychological environment provided by the mother permanently alters organ structure, cellular response and gene expression in her offspring," Kitlinkska says. "But our study shows the same thing to be true with fathers — his lifestyle, and how old he is, can be reflected in molecules that control gene function. In this way, a father can affect not only his immediate offspring, but future generations as well."

A newborn can be diagnosed with fetal alcohol spectrum disorder (FASD), even though the mother has never consumed alcohol.

"Up to 75 percent of children with FASD have biological fathers who are alcoholics, suggesting that preconceptual paternal alcohol consumption negatively impacts their offspring."

Joanna Kitlinska PhD, Associate Professor, Biochemistry, Molecular and Cellular Biology, Georgetown University Medical Center,

The report is a review of evidence from both human and animal studies on the links between fathers and heritable epigenetic programming.

Among the study topics reviewed:

• A father's advanced age correlates with elevated cases of schizophrenia, autism, and birth defects in his children

• A limited diet during father's pre-adolescence links to reduced risk of cardiovascular death in his children and grandchildren

• Paternal obesity links to enlarged fat cells, changes in metabolic regulation, diabetes, obesity and brain cancer

• Father's psychosocial stress links to negative behavior in his offspring

• Paternal alcohol use leads to decreased newborn birth weight, marked reduction in overall brain size and impaired cognitive function.

"This new field of inherited paternal epigenetic effects needs to be organized into clinically applicable recommendations and lifestyle alternations.

"To really understand the epigenetic influences on a child, we need to study the interplay between maternal and paternal effects, and not to consider each in isolation."

Joanna Kitlinska PhD

Historically, research into congenital defects has focused on maternal impacts on the fetal genome during gestation and prenatal periods. However, recent findings have sparked interest in epigenetic alterations of paternal genomes and its effects on offspring. This emergent field focuses on how environmental influences can epigenetically alter gene expression and ultimately change the phenotype and behavior of progeny. There are three primary mechanisms implicated in these changes: DNA methylation, histone modification, and miRNA expression. This paper provides a summary and subsequent review of past research, which highlights the significant impact of environmental factors on paternal germ cells during the lifetime of an individual as well as those of future generations. These findings support the existence of transgenerational epigenetic inheritance of paternal experiences. Specifically, we explore epidemiological and laboratory studies that demonstrate possible links between birth defects and paternal age, environmental factors, and alcohol consumption. Ultimately, our review highlights the clinical importance of these factors as well as the necessity for future research in the field.

The study's co-authors are Jonathan Day, MS, Soham Savani, MS, Ben Krempley, MS, and Matthew Nguyen, MS, graduates of Georgetown's Special Masters Program in Physiology.

This study was supported in part by National Institutes of Health grants (1R01CA123211, 1R03CA178809, R01CA197964 and 1R21CA198698).

About Georgetown University Medical Center
Georgetown University Medical Center (GUMC) is an internationally recognized academic medical center with a three-part mission of research, teaching and patient care (through MedStar Health). GUMC's mission is carried out with a strong emphasis on public service and a dedication to the Catholic, Jesuit principle of cura personalis -- or "care of the whole person." The Medical Center includes the School of Medicine and the School of Nursing & Health Studies, both nationally ranked; Georgetown Lombardi Comprehensive Cancer Center, designated as a comprehensive cancer center by the National Cancer Institute; and the Biomedical Graduate Research Organization, which accounts for the majority of externally funded research at GUMC including a Clinical and Translational Science Award (UL1TR001409-01) from the National Institutes of Health.


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May 19, 2016   Fetal Timeline   Maternal Timeline   News   News Archive   

A newborn can be diagnosed with fetal alcohol spectrum disorder —
(FASD) — even though the mother has never consumed alcohol.




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