menarhea

Menarche, sometimes referred to as menarhea, is the first menstrual period in human females and marks the Beginnning of reproductive maturity. The term menarche is the standard in medical literature; menarhea appears as a less common spelling variant in some sources.

Onset typically occurs during puberty, usually between ages 9 and 15, with an average around 12 to 13 years. Age at onset is influenced by genetics, nutrition, overall health, and environmental factors. After menarche, many girls experience irregular menstrual cycles for the first 1 to 2 years as the hypothalamic-pituitary-ovarian axis matures and ovulation may begin to occur more regularly.

Physiology and pattern: Estrogen drives the thickening of the endometrium, and the shedding during menses results in menstrual bleeding. In the early cycles, ovulation is often absent (anovulatory cycles), contributing to irregular timing. Typical cycle length in the years after menarche ranges from about 21 to 45 days; menses usually lasts 2 to 7 days and blood loss is commonly around 20 to 60 ml. Symptoms can include cramps, breast tenderness, mood changes, and fatigue, though experiences vary widely.

Variations and health considerations: Most adolescents can expect cycles to become more regular over 1 to 2 years. Seek medical advice if no menses by age 15 to 16, or if there is absence of secondary sexual characteristics by age 13. Medical evaluation is also warranted for very heavy bleeding, severe or persistent pain, unusually long cycles, or if pregnancy is possible.