Answer: Biological factors or influences such as genetic, biochemical factors on the gender.
Explanation: By way of definition,
the biopsychosocial model is a combined scientific model that looks at the interconnection between biology, psychology, and socio-environmental factors. The model specifically monitors how these aspects play a role in topics ranging from health and disease models to human development. This model was developed by George L. Engel in 1977. Though the biopsychosocial Model has received criticism about its limitations, but it continues to carry waves in the fields of psychology, health, medicine, and human development.
The biopsychosocial model explains the development of illness through the complex interaction of biological factors (genetic, biochemical, etc.), psychological factors (mood, personality, behavior, etc.) and social factors (cultural, familial, socioeconomic, medical etc.)
Engel clearly explained that the biomedical approach is flawed because the body alone does not contribute to illness. Instead, the individual mind (psychosocial model) plays a significant role in how an illness is caused and how it is treated. Engel suggested, a dialogue between the patient and the doctor in order to find the most effective treatment solution.
Engel felt the biopsychosocial model also allows physicians to better understand their patients' subjective view of their illness and suffering.
So from the question asked, Dr Ramirez idea of following the Psychosocial approach, will help him to understand his studies on the effects of stress on pregnant mothers and how this stress may influence gender expression in their children.