This study will recruit 50 healthy women with normal menstrual cycles aged 40-50, to investigate the expression of their NEI network and urine metabolomics.

Inclusion Criteria:

1. Healthy women with normal menstrual cycles aged 40-50.
2. The score of Kupperman index is less than 15.
3. Not alcoholics or smokers (past or smoking).
4. Get subjects informed consent process should comply with GCP requirements.

Exclusion Criteria:

1. Volunteers with heart, liver, kidney disease or acute or chronic gastrointestinal diseases, or with diseases of blood, endocrine, neurological and other systems.
2. Volunteers are participating in other clinical trials within 3 months.
3. Volunteers who donated blood or loosed blood heavily within 3 months.
4. Volunteers with previous history of mental illness, drug abuse or drug dependence.
5. Volunteers who took drugs within 14 days before the trail.

Healthy women with normal menstrual cycles aged 40-50