A fetus at the 75th percentile in growth is slightly larger than average but not a cause for concern, with risks to the mother increasing above the 90th percentile. Thymic cancer is rare, with no known risk factors, and immunotherapy is not recommended due to high risk of serious side effects.
A recent study published in Nature Communications explores the interplay between maternal and fetal genes, birth weight, and the growth of the cerebral cortex, shedding light on the impact of genetic variants and environmental factors, such as food availability, on brain development in the womb. The research, based on data from the UK Biobank, reveals that both maternal and fetal genetic variants associated with birth weight are linked to the size of the cerebral cortex, with the relative importance of these genes varying based on external conditions. The study suggests that ensuring healthy fetal growth, including access to nutritious food and healthcare, is crucial for optimal brain development and may have long-term implications for cognitive abilities and mental health.
Occasional cannabis use during pregnancy, even in the first trimester, can significantly reduce birth weight and head circumference of newborns, according to a study by researchers at Central Michigan University. Continued exposure throughout pregnancy resulted in the largest deficiencies. The study also found that occasional use, such as for morning sickness, may reduce fetal growth in the same way as continued use. The authors recommend that women quit marijuana use prior to becoming pregnant to avoid long-term adverse health and developmental outcomes.