Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Urogenital Block > L31 - Puberty and pregnancy > Flashcards

L31 - Puberty and pregnancy Flashcards

1
Q

Pregnancy duration

A

40 weeks (280 days after LMP)

38 weeks (266 days after fertilization)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Embryo development (first week)

A

Day 0 - oocyte

Day 1 - Pronucleus stage

Day 2, 3 - Cleavage Stage (2-cell to 8-cell stage)

Day 4 - Morula (through compaction)

Day 5 - Blastocyst

Day 6 - Hatching of blastocyst

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Placental Villi devlopment

A

(structure from internal to external)

1) Primary Villi (cytotrophoblastic layer + syncytiotrophblastic layer)

2) Secondary Villi (Mesodermal core + cytotrophoblastic layer + syncytiotropholastic layer)

3) Tertiary Villi (formation of villous capillary system in mesodermal core):

a) 4th week (endothelium + connective tissue + cytotrophoblast + syncytiotrophoblast)

b) 4th month (endothelium + syncytiotrophoblast)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Placenta function overview

A

1) Exchange of metabolic and gaseous products)
2) Production of hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Placental exchange of materials

A

1) Oxygen, carbon dioxide (fetal lung)
2) Nutrients, electrolytes (fetal gut)
3) Fluid volume regulation & waste disposal (fetal kidney)
4) Maternal antibodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Placental hormonal production

A

1) Cytotrophoblast:
- growth factors
- Hypothalamic releasing and inhibitory like hormones (e.g. corticotrophin releasing hormone CRH, thyrotropin releasing hormone TRH)
2) Syncytiotrophoblast
- Steroids e.g. estrogen & progesterone
- Pituitary hormone like hormone (e.g. human chorionic gonadotropin [hCG, LH like]; human chorionic somatomammotropin [HCS]; human placental lactogen [HPL, GH-like])

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Adaptive feature of fetal oxygen transport

A

To provide more oxygen to developing fetus, the following adaptive features:

1) Fetal hemoglobin has higher O2 affinity than materal Hg
2) Hg concentration higher in fetus
3) Bohr Effect (in placenta CO2 diffuse from fetal to materal, therefore lower O2 affinity of materal Hg and higher O2 affinity of fetal Hg)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Human chorionic gonadotropin

A

Origin: embryo and syncytiotrophoblast

Time: from 8-9 days after ovulation, decline around 10th week (as placenta overtake corpus luteum to produce steroids)

Function:

  • maintain corpus luteum to produce steroids and relaxin
  • increase fetal testosterone
  • increase fetal adrenal DHEA-S (substrate of placental estrogen)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Progesterone

A

Origin: syncytiotrophoblast

Time: Increase along the course of pregnancy

Functions:

  • increase oviductal and uterine secretion
  • increase decidual cell development
  • increase maternal ventilation
  • decrease maternal immune response to fetus
  • lead to uterine quiescence (decreased uterine contractility, oxytocin sensitivity, prostaglandin production)
  • prepare breasts for lactation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Estrogen

A

Mainly estriol

Source: Syncytiotrophoblast

Time: from Start of menstrual period, sudden drop at ovulation, increase along the course of pregnancy

Functions:

  • Increase synthesis of progesterone by increasing LDL cholesterol uptake
  • enlargement of uterus, female external genitalia
  • relaxing and softening of pelvic ligaments and pubic symphysis (with relaxin)
  • Growth of breast ductal structure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Maternal metabolism (anabolic phase)

A

1st maternal metabolic phase in pregnancy

Characterized by:

  • increased sensitivity to insulin
  • increased lipogenesis, decreased lipolysis
  • increased protein synthesis (leading to growth of breast, uterus, and essential masculature for pregnancy and labour)
  • increased glycogen synthesis and storage in liver and muscles
  • low or normal plasma level of glucose, amino acids, and fatty acid

Fetus undergo insignificant nutritional drain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Maternal metabolism (catabolic phase)

A

2nd phase of maternal metabolic phase of pregnancy, accelerated starvation

Characterized by:

  • increase resistance to insulin (due to placental HCS)
  • decreased lipogenesis and increased lipolysis
  • decreased protein synthesis
  • decreased glycogenesis
  • increased plasma levels of glucose, amino acids and fatty acid

Nutrient siphones to the fetus; fetus undergo accelerated weight gain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Maternal physiology In pregnancy

A

1) increased food intake; weight gain
2) Increased cardiac output and blood volume
3) increased ventilation
4) Increased urine formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Parturition defintion

A

Process by which the fetus, placenta and membranes are expelled from uterus through birth canal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Parturition involve the processes of…

A

1) rhythmic contraction of uterus
2) ripening of the cervix (to be softer and easily dilatable)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

initiation of labour

A

Involve mutiple maternal and fetal mechanisms

  • high redundancy
  • multiple triggers
  • once triggered, start positive feedback of event cascade, leading to parturition
17
Q

Fetal factors of labour

A

1) Mechanical stretch of uterine masculature
2) Hormonal factors
- oxytocin (fetal pituitary gland)
- cortisol (fetal adrenal gland; increase prostaglandin)
- prostaglandin (fetal amniotic and chorionic membranes; lead to membrane rupture, cervical dilatation, myometrial contractility)

18
Q

Names of stages of labour

A

1) Dilation stage
2) Expulsion stage
3) Placental stage

19
Q

Dilation stage of labour

A

1st stage of labour

  • begins with regular uterine contraction from fundus (leading to cervical dilatation)
  • Ends with full cervical dilatation

Duration: 10-12hrs (primigravidae); 6-8 hrs (multigravidae)

20
Q

Expulsion stage of labour

A

2nd stage of labour

  • begins with full cervical dilatation
  • ends when contraction of uterine muscles and voluntary muscles of abdominal wall and diaphragm force the fetus out of uterus via cervix

Duration: 1 hr (primigravida); 15-30 min (multigravida)

21
Q

Placental stage of labour

A

3rd stage of labour

  • begins from birth of child
  • ends with:
    i) separation of placenta from decidua tissues of uterus
    ii) expulsion of placenta and membranes
    iii) myometrial contraction (constriction of blood vessels to prevent excessive bleeding)

Duration: 10 min

22
Q

Uterine contraction pattern

A
  • contraction starts from fundus
  • spreads to cervix gradually
  • not simultaneous contraction which will squeeze but not push out
23
Q

Relaxin

A

Origin: first from corpus luteum (stimulated by hcg), then from placenta

Function:

a) relaxation of pelvic ligament
b) dilatation of cervix
c) suppression of uterine contraction (low potency during parturition as other hormones stimulate uterine contraction)

24
Q

Oxytocin

A

Origin: Produced from hypothalamus, released from posterior pituitary

Stimulation: tactile stimulation of reproductive tract esp cervix; high estrogen to progesterone ratio

Effect:

  • increase prostaglandin production and release
  • myometrial contraction
25
Q

Estrogen to progesterone ratio and labour

A

High estrogen:progesterone ratio around labour can

  • faciliate release of oxytocin
  • increase oxytocin receptor in myometrium
  • increase synthesus & release of prostaglandins
26
Q

Puberty

A
  • transition from non-reproductive to reproductive stage
  • involves physiological, morphological and behavioural changes
  • genetically determined
27
Q

Mechanism of puberty

A
  • unclear, possibly due to increase in gonadotrophin secretion at puberty (fetus produces gonadotrophins and stroids but restrained production before puberty)
  • Gonadostat hypothesis and hypothalamic maturation hypothesis
28
Q

Gonadostat hypothesis

A
  • Normally low threshold for negative feedback regulation of FSH/LH secretion by steroids (sensitive to low steroid levels)
  • Threhold is increased at puberty (therefore decreased sensitivity to steroids, leading to increased concentration of gonadotrophins and sex steroids)
29
Q

Hypothalamic maturation hypothesis

A
  • Maturation of CNS in puberty will increase output of hypothalamic GnRH

(Evidence:

  • young monkeys undergo pubertal change in pulsatile LH without gonads
  • gonadotrophin in agondal children, e.g. turner’s, increase the expected time of puberty without gonadal steroid influence)

Urogenital Block (39 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions