Menarche - The First Menstruation

Fertility exhibits itself at puberty with the first appearance of cervical mucus followed by the first menstruation. The first cycle is not always ovulatory. Menarche generally occurs between the ages of 9 to 16, and on average about age 13. Until about 18 to 20 years of age it is natural for a young woman’s menstrual cycle events to vary from the ideal. These variations are due to fluctuations in hormonal systems of an as yet immature reproductive system. A young woman may experience the following:

• the variation in the overall length of the cycle
• mucus patterns that vary from cycle to cycle
• a change in the nature of the menstrual flow from cycle to cycle
• cycles are not ovulatory

Young woman can reliably use charting to observe and understand their maturing reproductive system. The maturation of the reproductive system is associated with the laying down of lifelong bone health; brain, breast, and genital development, and the full expression of sexual response. Once a young woman reaches full reproductive maturity her menstrual cycles are generally regular and of optimum fertility.

Hormonal contraceptives are often used to “regulate” the cycles or suppress the menstruation of young woman who have yet to reach full reproductive maturity. The use of artificial contraceptive or menstrual suppressive hormones may interfere with a young woman’s body achieving full reproductive maturity; though once artificial hormone use is stopped the body makes every effort to restart the maturation process.

More often than not, a consistent healthy diet and lifestyle, as well as healthy thyroid gland function are the best regulators of ‘irregular’ menstrual cycles. Thyroid dysfunction is the single most common cause of menstrual cycle irregularity, so that would be the first thing a woman would want to have evaluated.

Two important factors affect the onset of menarche -- body composition and diet. Menarche begins when a girl acquires a ratio of body fat to weight and height (BFR) of 17 %. Twenty-two percent (22%) BFR is needed to maintain regular cycling and regular ovulation. Nutritional factors affect the onset of menarche, and deficiencies in key minerals and vitamins will delay or damage the menarche process. For example, a young girl needs to have adequate amounts of essential fatty acids, zinc, and vitamins A and D, among other nutrients for regular ovulation and healthy menstruation.  Furthermore, fundamental endocrine disorders of the thyroid and/or pituitary glands will alter or inhibit menarche or the maturation of the reproductive system and the attainment of regular and fertile menstrual cycles.