Abdi MD Endocrinologist Endocrine Research Center Research Institute for Endocrine Sciences Shahid Beheshti University of Medical Sciences 30 July 2015 Introduction Puberty is not a de novo event but rather a phase in ID: 779464
Download The PPT/PDF document "Normal Puberty Hengameh" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
Normal Puberty
Hengameh Abdi, MD, EndocrinologistEndocrine Research CenterResearch Institute for Endocrine SciencesShahid Beheshti University of Medical Sciences30 July 2015
Slide2Introduction:
Puberty is not a de novo event but rather a phase in the continuum of development of gonadal function and the ontogeny of the hypothalamic-pituitary-gonadal system from the fetus to full sexual maturation and fertility. During puberty, secondary sexual characteristics appear, and
the adolescent
growth spurt
occurs, resulting in the striking sex dimorphism of mature individuals; fertility is achieved, and profound psychological effects ensue.
2
Slide3Agenda:
Control of the onset of human puberty Hormonal changes during puberty Secondary sexual characteristics Adrenarche Other changes of puberty Puberty in Iran
3
Slide4The neuroendocrine control of puberty is
mediated by the hypothalamic GnRH-secreting neurosecretory neurons in the medial basal hypothalamus, which act as an endogenous pulse generator (oscillator).
(KISS1R)
4
Slide5Dual mechanism for the inhibition of puberty (Juvenile pause)
5
Styne
DM,
Grumbach
MM.
P
uberty. In:
Melmed
S, ed. Williams Textbook of Endocrinology. Elsevier Saunders 2011. 1088
Slide6Change in the pattern of pulsatile FSH and LH secretion
6
Styne
DM,
Grumbach
MM.
P
uberty. In:
Melmed
S, ed. Williams Textbook of Endocrinology. Elsevier Saunders 2011. 1088
Slide7Timing and onset of puberty:
Genetic neural control: Increased pulsatile release of GnRH caused by a balance in the inhibitory and excitatory factors Genetic factors are
estimated to
account for
50% to 80% of the variation in the onset of normal puberty.EthnicityEnvironmental factors:
Socioeconomic
factors
(such as family stress or the presence of an adult
nonbiologically
-related
male)
Nutrition
and
Physical activity
General health
Geography
Environmental endocrine
disruptors
(environmental contaminants that may affect endocrine processes)
7
Slide8Timing and onset of puberty:(cont.)
Body fat and Leptin Leptin appears to be one of several factors that influence the maturation of the gonadotropin-releasing hormone (GnRH) pulse generator. Serum leptin concentrations increase immediately before puberty in both genders.8
Slide9Mean plasma estradiol, FSH and LH in
prepubertal and pubertal females by pubertal stage of maturationGrumbach MM. Onset of puberty. In: Berenberg SR, ed. Puberty, Biologic and Social Components. Leiden, The Netherlands: H.E
.
Stenfert
Kroese, 1975:1-21.9
Slide10Mean plasma testosterone, FSH and LH in
prepubertal and pubertal males by pubertal stage of maturationGrumbach MM. Onset of puberty. In
:
Berenberg
SR, ed. Puberty, Biologic and Social Components. Leiden, The Netherlands: H.E. Stenfert Kroese, 1975:1-21.10
Slide11Laboratory information:
GnRH/GnRH agonist test The basal values of serum LH and FSH measured in modern supersensitive assays:Serum LH >0.2 IU/L on ICMA or >0.6 IU/L on IFMA are specific but not sensitive for the onset of puberty.
Urine LH
and FSH measured in ultrasensitive assays:A 5-fold rise in urinary FSH in boys and girls, with
a
50-fold
rise in urinary LH in boys and a
100-fold rise
in girls during puberty.
11
Slide12Laboratory information:(cont.)
Onset of puberty in boys is indicated by:Testes >2.5 cm in length (volume >3 ml)Serum testosterone concentration >50 ng/dLPubertal LH response to GnRH bolus
Pubertal pattern of LH
pulsatility
Serum testosterone >20 ng/dL predicts enlargement of testes to greater than 4 mL by 12 months
in 77% of cases and in 15 months in 100% of
case.
Prepubertal
boys have serum testosterone <10 ng/
dL
.
Prepubertal
girls have serum estradiol <5-10
pg
/
mL.
12
Slide13What to expect in girls during puberty?
13
Slide14Pubertal maturation in girls:
Increase in height velocity (rather than breast development or thelarche) is usually the first sign of puberty in girls, although breast budding is what most lay or medical observers first notice
.
A
substantial minority have pubic hair as the initial manifestation (pubarche).Menarche occurs, on average, 2.6 years after the onset of puberty (Menarche usually occurs in the 6-month
period
preceding or
following the fusion of the second and first distal
phalanges and
the appearance of the sesamoid
bone)
The
95
th
percentile
for menarche is 14.5
years.
14
Slide15Stages of breast development according to
Marshall and Tanner Stage 1: preadolescent; elevation of papilla only.Stage 2: breast bud stage; elevation of breast and papilla as a small mound, with enlargement of the areolar diameter.
Stage
3:
further enlargement of the breast and areola, with no separation of their contours. Stage 4: projection of the areola and papilla to form a secondary mound above the level of the breast.
Stage 5:
mature
stage; projection of the papilla only, resulting from recession of
the areola
to the general
contour.
15
Slide16Stages of
female pubic hair development according to Marshall and Tanner Stage 1: preadolescent; the vellus over the pubes is not further developed than that over the anterior abdominal wall; there is no pubic hair.Stage 2: sparse growth of long, slightly pigmented, downy hair that is straight or only slightly curled, appearing chiefly along the labia. Stage
3:
hair is considerably darker, coarser,
and curlier. The hair spreads sparsely over the junction of the pubic region. Stage 4: hair is adult in type, but the area covered by it is still considerably
smaller than
in most adults. There is no spread to the medial surface of the thighs.
Stage 5:
hair is adult in quantity and type, distributed as an inverse
triangle of
the classic feminine pattern. The spread is to the medial surface of
the thighs
but not up the
linea
alba or elsewhere above the base of the
inverse triangle
.
16
Slide17The sequence of events at puberty in females
The stage of breast development usually progresses along with the stage of pubic hair development in normal girls, but because different endocrine organs control these two processes, discordance can occur.17
Slide18The sequence of events at puberty in females
Root AW. J Pediatr. 1973; 83(1)18Because girls reach PHV about 1.3 years before menarche, there is limited growth potential after
menarche; most
girls grow only about 2.5 cm taller after
menarche, although there is a variation from 1 to 7 cm.
Slide19What to expect in
boys during puberty?19
Slide20Pubertal maturation in boys:
Growth of the testes is usually the first sign of puberty in the male. Pubertal testicular enlargement is indicated when the longitudinal measurement of a testis is greater than 2.5 cm (excluding the epididymis) or the volume is greater than 4 mL.
Almost all boys have an increase in testicular volume (≥3 mL) prior to the appearance of penile growth and pubic
hair.
20
Slide21Stages of male genital development according to Marshall and Tanner
Stage 1: preadolescent. Testes, scrotum, and penis are about the same size and proportion as in early childhood. Stage 2: the scrotum and testes have enlarged; the scrotal skin shows a change in texture and some reddening.
Stage 3:
growth
of the penis has occurred, at first mainly in length but with some increase in breadth; there is further growth of the testes and scrotum. Stage 4: the penis is further enlarged in length and breadth, along with
development of
the glans. The testes and scrotum are further enlarged. The scrotal
skin has
further darkened.
Stage
5:
genitalia are adult in size and shape. No
further enlargement
takes place after stage 5 is reached.
21
Slide22Stages of male pubic hair development according to Marshall and Tanner
Stage 1: preadolescent; the vellus over the pubic region is not further developed than that over the abdominal wall; there is no pubic hair.Stage 2: sparse growth of long, slightly pigmented, downy hair that is straight or
slightly curled
, appearing chiefly at the base of the penis.
Stage 3: hair is considerably darker, coarser, and curlier and spreads sparsely over the junction of the pubes.
Stage
4:
hair is adult in type, but the area it covers is still
considerably smaller
than in most adults. There is no spread to the medial surface of
the thighs
.
Stage
5:
hair is adult in quantity and type, distributed as an
inverse triangle
. The spread is to the medial surface of the thighs but not up
the
linea
alba or elsewhere above the base of
the inverse
triangle
.
22
Slide23The sequence of events at puberty in males
The growth and maturation of the penis usually correlates closely with pubic hair development, because both features are under androgen control.23
Slide24The sequence of events at puberty in
malesRoot AW. J Pediatr. 1973; 83(1)24
Slide25Peak Height Velocity: G (8.3 cm/
yr), B (9.5 cm/yr)Mean age (pubertal stage): G: 11.5 yr (2-3), B: 13.5 yr (3-4)
Grumbach
MM. J
Pediatr Endocrinol
Metab
. 2000; 13[
suppl
6]: 1439-1455
25
Slide26Adrenarche:
Adrenarche describes the maturational increase in adrenal androgen production, which begins at about six years of age in both girls and boys. Adrenarche seems to be unrelated to the pubertal maturation of the hypothalamic-pituitary-gonadal axis.Premature adrenarche refers to the rise in serum concentrations of adrenal androgens that causes the appearance of the pubic
hair:
Boys: <9 yr African American girls: <6 yr
White American girls:
<7
yr
26
Slide27Adrenarche:
(cont.)Adrenarchal androgens contribute to development of sebaceous glands and pubic hair (pubarche), and possibly to bone mineralization.27
Slide28Other changes of puberty:
Voice in boys: breaking of the voice occurs at approximately 13 years, and the adult voice is achieved by about 15 years. Facial hair in boys: P3 P5G5
Spermarche
is the age at first ejaculation (heralded by nocturnal sperm emissions and appearance of sperm in the urine): mean age of 13.5Axillary hair: B: 14 yr African American G: 12
yr
(White G: later
)
Acne
:
Acne vulgaris can be the first notable sign of puberty in a girl, preceding pubic hair and breast development; In boys, progresses with advancement through puberty. 100% of boys have
comedones
by genital stage 5.
28
Slide29Other changes of puberty:(cont.)
Vagina: Structural changes; secretion of clear or whitish discharge increases in the months before menarche. Ovaries: The ultrasound appearance of the
prepubertal
ovary changes with pulsatile gonadotropin secretion, and a multicystic appearance occurs with more than six follicles of at least 4 mm in diameter; During prepuberty
, the ovarian volume is 0.2 to 1.6 mL on
ultrasound scans
, and after the onset of puberty, the
volume increases
to 2.8 to 15
mL
.
Uterus:
The
length of the uterus increases from 2 to 3
cm to
5 to 8 cm; and the volume increases from 0.4 to 1.6
mL to
3 to 15
mL.
29
Slide30Puberty in Iran
Slide31Pubertal development in Iranian girls: Comparison with other countries
Country/TimeProvinceAge at B2Age at P2Age at Menarche
Iran,
2001-2004
Tehran, (n=4020)Mean (95% CI)10.15 (10-10.28)Mean (95% CI)10.48 (10.34-10.62)Mean (95% CI)
14.54 (14.47-14.63)
Iran,
2003-2004
Razzaghy-Azar
et al.
Tehran, (n=1420)
Median (10-90)
9.74 (8.23-11.94)
2.5
th
percentile: 7.42
97.5
th
percentile: 13.11
Median (10-90)
10.49 (8.86-12.17)
2.5
th
percentile: 7.03
97.5
th
percentile: 13.10
Median (10-90)
12.68 (11.27-15.96)
(n=399)
Iran,
2005-2006
Isfahan
(n=3192)
Median (10-90)
10.14 (8.33-11.95)
Median (10-90)
10.78 (9-12.48)
Median (10-90)
12.65 (11.18-14.11)
USA,
1997
Mean (SD)
9.96 ± 1.82
Mean (SD)
10.51 ± 1.67
Mean (SD)
12.88 ± 1.20
Denmark, 1991-1993
Mean
10.88
Mean
11.29
Mean
13.42
Netherlands,
1965-1997
Mean
10.5
Mean
10.8
Mean
13.15
UK, 1969
Mean
11.1
Mean
11.7
Mean
12.9
Slide32Probability of different stages of
breast development in 6–18-year-old Iranian girlsRazzaghy-Azar M. Annals of Human Biology. 2006; 33(5/6): 628–63332
Slide33Probability of different stages of
pubic hair development in 6–18-year-old Iranian girlsRazzaghy-Azar M. Annals of Human Biology. 2006;
33(5/6): 628–633
33
Slide34Probability of
the occurrence of menarche in 6–18-year-old Iranian girlsRazzaghy-Azar M. Annals of Human Biology. 2006; 33(5/6): 628–63334
Slide35Pubertal development in Iranian boys: Comparison with other studies
Country/TimeProvinceP2G2Iran, 2003-2004
Tehran, (n=792)
Median (10-90)
10.34 (6.84-13.10)Median (10-90)9.01 (?-11.84)
USA,
1995
Ohio
(n=78)
Mean (SD)
11.2 ± 0.8
Mean (SD)
11.2
± 0.7
USA,
2001
(n=2114)
African-Americans 11.2
Whites 12.0
African-Americans 9.5
Whites 10.1
35
Slide36Probability of different stages
of pubic hair and genital developmentin 6–15-year-old Iranian boys
Razzaghy
-Azar M. Journal of Iran University of Medical Sciences. 2006
36
Slide37Timing of puberty in Iranian girls according to their living areas
The lowest age of menarche: 1) Tehran: 11.99 ± 1.35 yr 2) Fars: 12.40 ± 1.27 yrThe lowest age of thelarche:
1)
Ghazvin-Zanjan: 8.97 ± 1.45 yrHighest age of pubarche:
1)
Kordestan-Lorestan-Ilam
region: 10.70
±
1.23
yr
Motlagh
ME. J Res Med Sci. 2011; 16(3): 276-281
37
Slide38Thanks for your patience!