Our Gemara on amud aleph discusses the damage that mustard might cause to a nearby beehive, and the various liabilities that neighbors have toward each other:

“One must likewise distance mustard from bees that are in a neighbor’s field.”

Rashi explains that the mustard is sharp and that taste causes the bees to seek out a sweet taste afterward, inducing them to consume their own honey. Which is, of course, a loss of honey yield for the farmer.

Gilyonei Hashas references Rashi’s explanation to a different Gemara in Kesuvos (60b) which discusses a plethora of ways in which a mother's dietary choices and behaviors can affect the child in utero.  As one example, “One who eats mustard during pregnancy will have gluttonous children.” Gilyonei Hashas is suggesting a mechanism similar to our Gemara. The mustard will cause a craving for sweetness, and apparently the sweet tooth will lead to craving food in general, and to gluttony.

The ancient belief and wisdom, that what occurs physiologically to the mother influences the formation of the fetus has been demonstrated by science.  The baby is in a bath of mother’s hormones, and as nerve pathways are forming, the adaptive mechanisms of the brain may already be influenced to react. Various responses become triggered way before the child has any of his or her own life experiences.  According to researchers Wu et. al. (Wu, Y., De Asis-Cruz, J. & Limperopoulos, C. “Brain Structural And Functional Outcomes In The Offspring Of Women Experiencing Psychological Distress During Pregnancy”. Molecular Psychiatry (2024)):

• In-utero exposure to maternal psychological distress is increasingly linked with disrupted fetal and neonatal brain development and long‐term neurobehavioral dysfunction in children and adults. Elevated maternal psychological distress is associated with changes in fetal brain structure and function…
• Disturbed brain microstructure and functional connectivity have been reported in the offspring months or even years after exposure to maternal distress during pregnancy. Additionally, adverse child neurodevelopment outcomes such as cognitive, language, learning, memory, social-emotional problems, and neuropsychiatric dysfunction are being increasingly reported after prenatal exposure to maternal distress. 
• Exposure to prenatal maternal stress is shown to have enduring and wide-ranging consequences on brain development in the offspring, including altered regional brain volumetric growth, cortical folding, metabolism, microstructure, and functional connectivity. In addition, the long-term neurodevelopmental impairments of the offspring include a spectrum of cognitive, language, social-emotional, learning and memory, and behavioral problems, as well as neuropsychiatric dysfunction.

In the 21st Century, it would be unthinkable for a middle class pregnant woman to neglect pre-natal vitamins and routine blood tests, sonograms etc.  We see from these findings, that emotional care for the mother is also an important part of pre-natal health.  If the mother is suffering from depression, anxiety and/or relational discord, getting proper help is important and can have significant impact on future family life and child development.  A Jewish mother would never get drunk while pregnant, so neither should she or her spouse   allow for intense emotional anguish.  There is a great wisdom to the old-school practices of spoiling a pregnant woman, and being extra forgiving and generous during pregnancy, as the family’s future may depend on it.