So it was time to research this nausea issue, and to my relief have found the following information:
Nausea can occur due to a lack of estrogen in the body during menopause. Low estrogen levels also affect fat distribution and this result in bio-chemical changes in the gut. These changes can trigger several of the other symptoms of menopause and nausea, too.
Menopause symptoms and nausea often begin during peri-menopause, the stage before actual menopause begins. Nausea can be particularly problematic in the mornings, much like it is during pregnancy. This could be due to hormonal fluctuations or diet, but more research on the topic needs to be carried out. There are various cases where menopausal symptoms and nausea are related:
34 Menopause Symptoms-Nausea