https://humanap.community.uaf.edu/wp-content/uploads/sites/848/2025/04/Oogenesis-steam-project-3.pdf

For my steam project, I researched Oogenesis and female egg development, specifically exploring  how maternal and grandmaternal generations can affect the health of future ones. I was particularly interested in the effect of unwanted factors in pregnancy, such as extreme stress or smoking. This will cover course objectives 8 and 9: “Compare and contrast spermatogenesis and ovulation”, and “Know the structure and function of reproductive organs”.

Oogenesis starts in the primordial germ cells during fetal life at approximately nine weeks when oogonia enters meiosis. (Ducreux, et al., 2023) In a female human embryo, the oogonia divide rapidly during the second to the seventh month of gestation, forming around 7 million germ cells. This number drops after the seventh month, where most oogonia will die and the remaining oogonia will enter the first meiotic division. These cells are called the primary oocytes, which go onto the diplotene stage. (Gilbert, 2015). The maturation of eggs is stopped until puberty where Luteinizing Hormone triggers the development of a dominant follicle until the oocyte reaches metaphase of meiosis II (Ducreux, et al., 2023).

Because Oogenesis begins in fetal life, pregnancy can affect the child being carried but also the oocytes and consequently, future grandchildren. Common negative exposures during pregnancy include high levels of stress, depression and smoking. In Australia, around 16% of women experience postpartum depression, but around 50% of those women experienced depression while they were pregnant (Lewis, et al., 2015). Studies have shown that mothers with high levels of cortisol while pregnant can impact the responsibility of neuroendocrine systems related to stress in later years (Lewis, et al., 2015). Infants of mothers with elevated cortisol levels even showed increased fussiness and negative reactivity, even after controlling for postpartum depression (Lewis, et al., 2015). Other associations between exposure to antenatal depression and anxiety have been reduced birth size with implications for future growth rate, decreased abdominal growth, slower fetal weight gain, and reduced fetal head circumference growth (Lewis et al., 2015).

However, even the impact of maternal mental health on fetal growth has been shown to have less than one third of the impact than the effect of maternal smoking during pregnancy. Epigenetic studies have pointed out that there are consistent associations between hypomethylation of the AHRR gene in neonatal blood and smoking, which may even translate to the grandchild generation (Lewis, et al., 2015). Other studies suggest that in-utero exposure to tobacco can develop heritable mutations in germ cells or gene expressions (Rillamas Sun, et al., 2013). The relationship between grandmother’s smoking behavior also varies by time of birth, which suggests a change in tobacco content or other toxic ingredients found in cigarettes based on time period. Grandmother’s born in 1904-1928 did not affect their grandchildren’s birth weight when smoking, but grandmother’s born in 1929-1945 had heavier grandchildren if their mother’s also smoked. Grandchildren’s birth weights were lowest when the mother smoked during pregnancy, but the grandmother abstained (Rillamas Sun, et al., 2013). There are many gaps in literature and variables that contribute to these findings.

Even with a variety of smoking effects on transgenerational health, other studies have shown that psychological stress in grandmaternal pregnancies consistently alter grandchildren generations. In animals, we’ve been able to show that maternal nutrition during pregnancy on the hypothalamic pituitary adrenal axis function and heart structure is observed in both the second and third generations. Rats that were exposed to excess glucocorticoids showed reduced birthweight and glucose intolerance into the third generation (Serpeloni, et al., 2017). In a study on the multigenerational epigenetic effects of psychological stress in human pregnancies, results showed that grandmaternal exposure to domestic violence during pregnancy was associated with 27 differentially methylated CpG sites in children. The most altered genes were the ones involved in the circulatory system processes and congenital abnormalities (Serpeloni, et al., 2017). The study stated that: “To the best of our knowledge, this is the first investigation in humans of the impact of grandmaternal psychosocial stress during pregnancy on grandchild DNA methylation. Our data suggest that not only exposure to toxins during pregnancy, but also grandmaternal psychosocial stress can be translated into DNA methylation changes in the grandchild.” (Serpeloni, et al., 2017).
To represent these effects, I used a painting as my project medium. I painted a grandmother, mother, and grandchild in the picture. The grandmother is pregnant, smoking a cigarette. In her womb, her daughter sits, also pregnant with a baby shown inside her. There are three generations, because oogenesis starts in the womb, so the eggs of all a woman’s future grandchildren are technically present in her as she gestates her daughter. I painted the smoke from the cigarette swirling down into the mother and into her baby, because of the transgenerational effects of smoking while pregnant. Though I researched the generational effects of smoking and other factors such as mental illnesses or stress, I decided only to portray smoking in the painting because it’s easiest to visualize and most impactful to the viewer, in my opinion. To emphasize the ripple effect of a pregnancy, I used gradient colors between the three generations. There is primarily green surrounding the grandmother, then blue around the mother, and finally purple around the baby. These colors are sequential in the color wheel and can easily blend into one another. Even though purple is more separated from green, it still carries its influence. 

References

Ducreux, B., Ferreux, L., Patrat, C., & Fauque, P. (2023). Overview of Gene Expression Dynamics during Human Oogenesis/Folliculogenesis. International Journal of Molecular Sciences, 25(1), 33–33. https://doi.org/10.3390/ijms25010033

Gilbert, S. (2015). Oogenesis. Nih.gov; Sinauer Associates. https://www.ncbi.nlm.nih.gov/books/NBK10008/

Lewis, A., Austin, E., Knapp, R., Vaiano, T., & Galbally, M. (2015). Perinatal Maternal Mental Health, Fetal Programming and Child Development. Healthcare, 3(4), 1212–1227. https://doi.org/10.3390/healthcare3041212

Rillamas-Sun, E., Harlow, S. D., & Randolph, J. F. (2013). Grandmothers’ Smoking in Pregnancy and Grandchildren’s Birth Weight: Comparisons by Grandmother Birth Cohort. Maternal and Child Health Journal, 18(7), 1691–1698. https://doi.org/10.1007/s10995-013-1411-x

Serpeloni, F., Radtke, K., de Assis, S. G., Henning, F., Nätt, D., & Elbert, T. (2017). Grandmaternal stress during pregnancy and DNA methylation of the third generation: an epigenome-wide association study. Translational Psychiatry, 7(8), e1202–e1202. https://doi.org/10.1038/tp.2017.153