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Course: MCAT > Unit 4

Lesson 1: Foundations of behavior passages

Physiological needs and pregnancy


The physiological processes of the human body are controlled by mechanisms that seek to maintain homeostasis. When the body is not in a state of balance, we are motivated to take action that brings us back to a homeostatic state. For example, physiological cues of hunger motivate eating behaviors, while sexual cues motivate reproduction.
The brain couples motivation, needs, and physiological processes, and regulates them through automatic and unconscious mechanisms. For example, females are physically able to carry a child for nine months before birth. From the age of puberty to menopause, women have monthly menstrual cycles that prepare them for bearing a child. Before ovulation, small amounts of estrogen are secreted from the ovary. Estrogen stimulates the release of gonadotropin releasing hormone (GnRH) from the hypothalamus and consequently leutinizing hormone (LH) from the anterior pituitary. LH release into the bloodstream also causes the release of additional estrogen, which again works to increases GnRH and LH levels in the blood. After ovulation, the corpus luteum in the ovary secretes progesterone since the LH levels are high. Progesterone is able to inhibit GnRH and LH production from the brain when those levels of hormones are too high in the blood.
When this cycle is not in harmony, women can experience issues with infertility. Annie, a thirty five year old female, visits her gynecologist with concerns about her ability to have children. After interviewing Annie, her doctor becomes concerned about her stress levels. She asks Annie to track her monthly cycle for six months using an at-home fertility kit, and stop into the office on the sixth cycle day of each month to provide a salivary cortisol sample and complete a written stress test. Annie’s written stress test scores at each point are outlined in Table 1; scores closer to 100 indicate extreme stress levels. She finds that Annie’s salivary cortisol levels are also significantly higher than normal rates at each assessment point.
MonthStress Score
Month 182.8
Month 285.7
Month 392.5
Month 490.2
Month 583.4
Month 684.3
Based on Annie's stress test results, her gynecologist suggests making significant changes to her day to day life. She tells Annie to start practicing meditation and to take frequent light walks throughout the day. Her gynecologist believes in the Yerkes-Dodson law and feels that if Annie is more calm, her ability to conceive will improve. What is Annie's gynecologist trying to promote?
Choose 1 answer: