The interplay between oxytocin and stress hormones is a fascinating aspect of our neuroendocrine system. Cortisol and oxytocin are both regulated by the hypothalamus, a critical part of the brain that helps maintain hormonal balance. The hypothalamus plays a pivotal role in maintaining the balance between these hormones.

Oxytocin is produced in the paraventricular nucleus inside the hypothalamus, a small but crucial part of the brain that regulates many autonomic functions. From the hypothalamus, oxytocin is transported to and released by the posterior pituitary gland into the bloodstream which then travels to the breast and causes the pulsatile contractions known as the Milk Ejection Reflex (let down).

In response to stress, the hypothalamus releases corticotropin-releasing hormone (CRH). CRH prompts the anterior pituitary gland to secrete adrenocorticotropic hormone (ACTH). ACTH then stimulates the adrenal glands to release cortisol and adrenaline into the bloodstream, preparing the body for a 'fight-or-flight' response. The hypothalamus coordinates the release of CRH and oxytocin, attempting to balance the stress response with mechanisms that promote recovery and resilience

These hormones counteract each other: cortisol increases alertness and stress, while oxytocin reduces anxiety and fosters calmness, helping to restore equilibrium in the body's stress response system

What Causes Let-Down Nausea?

The sudden surge of oxytocin, combined with fluctuating levels of other hormones released by the hypothalamus, can activate the parasympathetic nervous system, which can sometimes trigger nausea. This response is similar to the body's reaction to certain stressors or stimuli

Breastfeeding is both physically and emotionally demanding. Anxiety, lack of sleep, and overall stress can exacerbate nausea during let-down

Blood Sugar Levels: Low blood sugar, a common issue for new mothers who might skip meals or eat irregularly, can also cause or worsen nausea as hormones are fluctuating during breastfeeding

Managing breastfeeding nausea

Hydration and Nutrition: Ensure you're staying well-hydrated and eating balanced meals regularly. Small, frequent meals rich in protein and complex carbohydrates can help stabilize blood sugar levels and reduce nausea, especially when eaten a few minutes before moving milk

Relaxation Techniques: Practice deep breathing, meditation, or gentle yoga to reduce overall stress. Creating a calm and comfortable environment during breastfeeding or pumping  can help