Child Development

Nelson, Katherine. ‘‘The Psychological and Social Origins of Auto-
biographical Memory.’’ Psychological Science 1 (1993):1–8.
Molly Carter Imhoff
Lynne E. Baker-Ward

MENARCHE

Menarche refers to the first menstrual flow experi-
enced by a girl during puberty. Menstruation means
that the physiological and hormonal changes under-
lying reproductive processes have matured sufficient-
ly to produce the endometrial lining of the uterus,
which is sloughed off at the end of the menstrual cycle
if implantation of a fertilized ovum has not occurred.

Menarche typically occurs after other pubertal
changes are well established, and marks the comple-
tion of puberty. The mean age of menarche for girls
in the United States is twelve, but it may occur nor-
mally from ages ten to sixteen. Early menstrual cycles
are often irregular and may include no ovulation or
multiple ovulations.

Menarche often is acknowledged by family or
community rituals, recognizing the adolescent’s en-
trance into womanhood and sexual potential. Chal-
lenges of adolescence for a girl include incorporating
the new status and potential into her self-concept and
coping with reactions of family and peers.

See also: ADOLESCENCE; MENSTRUAL CYCLE;
PUBERTY

Bibliography
Grumbach, Melvin M., and Dennis M. Styne. ‘‘Puberty: Ontogeny,
Neuroendocrinology, Physiology, and Disorders.’’ In Jean D.
Wilson and Daniel W. Foster eds., Williams Textbook of Endocri-
nology, 9th edition. Philadelphia: Saunders, 1998.
Herman-Giddens, Marcia E., Eric J. Slora, Richard C. Wasserman,
Carlos J. Bourdony, Manju V. Bhapkar, Gary G. Koch, and
Cynthia M. Hasemeier. ‘‘Secondary Sexual Characteristics
and Menses in Young Girls Seen in Office Practice: A Study
from the Pediatric Research in Office Settings Network.’’ Pedi-
atrics 99 (1997):505–512.
Lawrence G. Shelton

MENSTRUAL CYCLE

The menstrual cycle is a periodic flow of blood and
cells from the lining of the uterus in human females
and the females of most other primates, occurring
about every twenty-eight days. The beginning of men-
struation, or menarche (the first menstrual period),
typically starts between the ages of ten and seventeen
and is a sign of readiness for childbearing.

During each cycle, the lining, or endometrium, of
the uterus experiences a rapid generation of cells and

vein-filled channels in preparation for pregnancy.

Halfway through the cycle, an ovum (egg) is released

from an ovary. The ovum passes through the fallopi-

an tube, and if fertilized by a sperm, the ovum is im-

planted in the uterus, and the thickened lining helps

support the pregnancy. If the ovum is not fertilized,

the tissue and blood are shed.

The many myths and taboos related to menstrua-

tion have caused some cultures to chastise it as ‘‘un-

clean’’ or a ‘‘curse.’’ For a young girl, menarche is

simply related to growth and body weight. Signs of

puberty can begin after the age of eight, but early

physical maturation may result in social pressure be-

cause of increased attention.

See also: ADOLESCENCE; CONTRACEPTION;

MENARCHE; PUBERTY

Bibliography

Gorman, Christine. ‘‘Growing Pains: What Happens When Puberty

Comes Too Soon in Your Child—and What You Can Do

about It.’’ Time (August 21, 2000):84.

Peters, Diane. ‘‘It’s Wonderful Being a Girl.’’ Chatelaine (June

2000):76.

Beth A. Kapes

MENTAL AGE

Mental age refers to an age-normed level of perfor-

mance on an intelligence test, and it became a popu-

lar way of referring to ‘‘mental level’’ as measured by

the Binet-Simon Scale of 1908. The Binet-Simon

Scale identified the academic skills typical of specific

age groups. In 1912 William Stern used chronological

age as a denominator to be divided into mental age,

resulting in an intelligence quotient. In 1916 Lewis

Terman multiplied this intelligence quotient by 100

(to eliminate the decimal places) and called the result

an IQ score. Terman’s formula of mental age divided

by chronological age multiplied by 100 became popu-

larized as the formula for calculating a person’s IQ.

Adult intelligence does not change from year to year

so the concept of mental age is less meaningful when

discussing adults. Contemporary IQ tests use cumula-

tive indexes to determine scores rather than the cal-

culation of IQ scores based upon Terman’s formula.

A contemporary equivalent of mental age is the Stan-

dard Age Score of the Stanford-Binet IQ test, which

was formulated in 1987.

See also: MILESTONES OF DEVELOPMENT

Bibliography

Anastasi, Anne. Psychological Testing. New York: Macmillan, 1988.

Fancher, Raymond. Pioneers of Psychology. New York: Norton, 1990.

Francine Smolucha

260 MENARCHE