Some people do notice that their hair can be thicker and fuller when pregnant, and this is a hormonal fluctuation.

Birth control pills, like Yaz, which can regulate the hormonal fluctuations that spark breakouts.

Breakthrough bleeding is likely due to hormonal fluctuations.

During this time, hormonal fluctuations can cause havoc in a woman's body.

For instance, one woman is having periods and the other has normal hormonal fluctuations.

Antibiotics and hormonal fluctuations could play a role but not everyone is susceptible.

Stress may also play a role and, in women, hormonal fluctuations may exacerbate symptoms.

For example, hormonal fluctuations related to menstruation or pregnancy are often responsible for breast tenderness.

Some degree of breast tenderness is normal, caused by hormonal fluctuations from:

She added, "There has been speculation that maybe hormonal fluctuations could have an effect on susceptibility and the study here supports that."