Reproductive Endocrinology Flashcards
1
Q
compare oogenesis and spermatogenesis in terms of how long the process takes till completion?
A
oogenesis: many years
spermatogenesis: 72 days
2
Q
compare oogenesis and spermatogenesis in terms of where it begins?
A
oogenesis: in utero
spermatogenesis: in puberty
3
Q
compare oogenesis and spermatogenesis in terms of cessation?
A
oogenesis: ceases at menopause
spernmatogenesis: doesnt cease
4
Q
which process is cyclical- oogenesis or spermatogenesis?
A
oogenesis
5
Q
what is the earliest recognisable germinal cell?
A
primordial germ cell
6
Q
are primordial germ cells capable of mitosis or meiosis?
A
mitosis
7
Q
where do primordial germ cells migrate to by week 6 of embryo development?
A
genital ridge
8
Q
what female germ cells are the first cells able to undergo meiosis?
A
oocytes
9
Q
what germ cells complete the last pre-meiotic division in order to become oocytes?
A
oogonia
10
Q
what cells are formed when oocytes undergo their first meiotic division?
A
pirmary oocyte + first polar body
11
Q
what cells are formed when primary oocytes undergo their second meiotic division?
A
secondary oocyte + two polar bodies
12
Q
when does the primary oocyte undergo its second meiotic division?
A
after sperm entry
13
Q
do sperm have equal or unequal meiosis?
A
equal
14
Q
do oocytes have equal or unequal meiosis?
A
unequal
15
Q
compare oocytes and sperm in terms of presence of stem cell pool?
A
oocytes- no stem cell pool
sperm- stem cell pool
16
Q
how long is the average ovarian cycle?
A
28 days
17
Q
what are the 2 phases of the ovarian cycle?
A
1st phase: follicular
2nd phase: luteal
18
Q
what marks the end of the follicular phase and the beginning of the luteal phase in the ovarian cycle?
A
ovulation
19
Q
what is the name of the single layer of granulosa cells which surrounds the primary oocyte?
A
primary follicle
20
Q
what cells is the primary follicle made of?
A
single layer of granulosa cells
21
Q
what is atresia of the primary follicle?
A
degeneration of follicle to scar tissue
22
Q
the atrum is a section within the secondary follicle, what does this contain?
A
follicular fluid
23
Q
what is lutenisation?
A
transformation of the follicular cells left behind after ovulation into the corpus luteum
24
Q
what hormone does the corpus luteum secrete?
A
progesterone
25
how long will the corpus luteum survive if no fertilisation takes place?
14 days
26
what phase of the ovarian cycle does degeneration of the corpus luteum indicate?
the start of the follicular phase
27
what hormone produced from the hypothalamus stimulates the anteiror pituitary to secrete FSH and LH?
gonadotrophin releasing hormone
| GnRH
28
As the follicle develops in the follicular phase, what hormone level noticeably rises?
oestrogen
29
what cells within the follicles produce androgens which are converted to oestradiol?
theca cells
30
what cells within the follicles convert the androgens into oestradiol?
granulosa cells
31
what hormone does oestrogen have negative feedback over?
FSH from the anterior pituitary gland
32
what cells within the dominant follicle express LH receptors?
granulosa cells
33
after the LH peak, how long is it before ovulation occurs?
on average 38 hours
34
what test can be done to look for ovulation using LH?
LH profile
| -using urinary dipsticks over a few days
35
what test can be donw to look for ovulation using progesterone?
day 21 progesterone
36
the lack of which hormone causes the degeneration of the corpus luteum?
hCG
37
what is formed by the degeneration of the corpus luteum?
corpus albicans
38
what hormone stimulates the interstitial Leydig cells of the seminiferous tublules to produce testosterone?
LH
39
what hormones stimulate spermatogenesis?
FSH
| testosterone
40
what hormones does testosterone have negative feedback control of?
GnRH
| LH
41
where is pregnenolone produced in the ovaries? (from cholesterol)
```
granulosa cells (oestrogen production)
corpus luteum (progesterone production)
```
42
what is the effect of oestrogen on the intracellular progesterone receptor?
increases numbers of the receptor
43
what is oligomenorrhoea?
reduction in frequency of periods to less than 9 per year
44
what is primary amenorrhoea?
by the age of 16 individual has not ever menstuated
45
what is secondary amenorrhoea?
cessation of periods for over 6 months in an individual who has previously menstruated
46
what are the 2 physiological causes of amenorrhoea?
pregnancy
| post-menopausal
47
what must you consider in an individual with primary amenorrhoea?
congenital problem
| eg Turner's
48
what are the 4 subgroups of causes of secondary amenorrhoea?
ovarian cause
uterine cause
pituitary cause
hypothalmic cause
49
what are the 3 main causes of secondary amenorrhoea of ovarian cause?
- polycystic ovarian syndrome
- premature ovarian failure
- congenital problem with ovarian development
50
what is the main cause of secondary amenorrhoea of uterine cause?
uterine adhesions
51
why might uterine adhesions cause secondary amenorrhoea?
unable to shed lining
52
what are the 2 main causes of amenorrhoea of pituitary cause?
high PRL
| hypopituitarism
53
what are the 4 mains causes of amenorrohea of hypothalmic cause?
weight loss
over exercise
stress
infiltrative
54
what is the name of the syndrome in which individuals have an absence of periods and an inability of smell?
Kallmann's syndrome
55
what tests must be done in all patients with oligomenorrhoea or amenorrhoea?
LH, FSH, oestradiol
| thyroid function, prolactin
56
what is female hypogonadism?
low levels of oestrogen
57
what is premature ovarian failure?
when the ovaries have become depleted of eggs early
58
what are the differences between primary and secondary hypogonadism in terms of hormone levels?
(in females)
both have low oestrogen level
primary: high LH/FSH (hypergonadotrophic hypogonadism)
secondary: low LH/FSH (hypogonadotrophic)
59
what age must amenorrhoea occur below for it to be classed as premature ovarian failure and not just post-menopause?
below 40 years of age
60
if a patient has FSH higher than 30, what does this suggest?
the woman is post menopausal
61
what is idiopathic hypogonadotrophic hypogonadism?
absent or delayed sexual development associated with low levels of gonadotrophin and sex hormones in the absence of anatomical/functional defects of hypothalamic-pituitary gonadal axis
62
what is the major defect in idiopathic hypogonadotrophic hypogonadism?
the inability to activate pulsatile GnRH secretion during puberty
63
what is kisspeptin?
an upstream regulator of GnRH which stimulates it's secretion
64
is Kallmann's Syndrome hypertrophic hypogonadism or hypotrophic hypogonadism?
hypotrophic hypogonadism
65
why can hyperprolactinaemia induce hypogonadalism?
increased PRL can inhibit kisspeptin neurones, this reduces GnRH levels
66
what is hirsutism?
excess hair
| if in a women, there is a male pattern hair distribution
67
what is hirsutism caused by?
excess circulating androgen
68
what are the 5 main causes of hirsutism?
```
PCOS
familial
idiopathic
non-classical congenital adrenal hyperplasia
adrenal or ovarian tumour
```
69
what are the red flag signs for a patient with hirsutism?
raipid onset hirsutism
| signs of virilisation
70
what is congenital adrenal hyperplasia?
an inherited group of disorders characterised by a deficiency in one of the enzymes necessary for cortisol
71
what enzyme is deficient in 90% of cases of congenital adrenal hyperplasia?
21alpha-hydroxylase
72
when is classic congenital adrenal hyperplasia typically diagnosed?
infancy
73
when is non-classic congenital adrenal hyperplasia typically diagnosed?
adolescence/adulthood
74
why do patients with congenital adrenal hyperplasia have virilisation, hirtuism and sometimes infertility?
due to increased levels of testosterone
75
is the production of androgens in congenital adrenal hyperplasia ACTH-dependant or independent?
ACTH- dependant
76
why are patients with late onset CAH given low dose glucocorticoid?
to suppress ACTH drive
| reduces androgens
77
what is the unusual karotype of a women with Turner's syndrome?
XO
78
what is gonadal dysgenesis?
absent ovaries but no chromosomal abnormality
79
what is testicular feminisation caused by?
being insensitive to androgens
80
compare primary and secondary male hypogonadism in terms of hormone levels?
both have low testosterone
primary: high LH/FSH
secondary: low LH/FSH
81
what is the unsual karotype of Kleinfelter's syndrome?
XXY
82
does kleinfelter's syndrome cause primary or secondary hypogonadism?
primary hypogonadism
83
at what time of day should you measure testosterone?
9am
84
what is Whipple's triad and what does it indicate?
- presence of symptoms of hypoglycaemia
- documented low blood sugar
- relievation of symptoms by glucose adminstration
(all without having taken insulin)
--> insulinoma
85
what cells in the pancreas are insulinomas derived from?
pancreatic beta cells
86
what are the 2 types of hypoglycaemic symptoms?
autonomic
| neuroglycopaenic
87
what are 3 drugs used in the management of insulinomas?
- diazoxide
- hydrochlorothiazide
- octreotide
88
compare the frequency of pulses of FSH and LH stimulated by GnRH?
low frequency pulses of FSH
| high frequency pulses of LH
89
the mid-cycle peak of LH stimulates what process?
ovulation
90
what 3 places within the body can oestrogen be physiologically produced from?
follicles within ovary
adrenal cortex
placenta
91
what 2 hormones does oestrogen have negative feedback upon?
FSH
| prolactin
92
what hormone does oestrogen have positive feedback upon?
LH
93
what hormone does progesterone have negative feedback upon?
LH
94
compare oestrogen and progesterone in terms of what they do to the cervical mucous?
oestrogen: makes fertile mucous
progesterone: makes (thick) infertile mucous
95
what hormone has a thermogenic effect within the ovarian cycle?
progesterone
96
what does a positive 21 day progesterone confirm?
ovulation
97
what are the 3 WHO classifications of causes of anovulation?
1. hypothalamic pituitary failure
2. hypothalamic pituitary dysfunction
3. ovarian failure
98
is anovulation due to hypothalmic pituitary failure hypogonadotrophic or hypergonadotrophic hypogonadism?
hypogonadotrophic hypogonadism
99
compare the levels of FSH/LH/oestrogen in a patient with hypothalamic pituitary failure causing anovulation?
low FSH, LH and oestrogen
100
what is the result of a progesterone challenge test in a patient with hypothalamic pituitary failure causing anovulation?
negative
101
does a patient with hypothalamic pituitary failure tend to have amenorrhoea or oligomenorrhoea?
amenorrhoea
102
what is the primary defect in hypothalamic pituitary failure?
defect in production of GnRH or FSH/LH
103
compare pulsatile GnRH with gonadotrophin (FSH/LH) daily injections for the treatment of hypothalamic anovulation in terms of multiple pregnancy rate?
pulsatile GnRH: multple pregnancy rate not increased
LH/FSH daily injections: higher multiple pregnancy rates
104
what is the main problem in hypothalamic pituitary dysfunction causing anovulation?
inabiltiy of the ovaries to read the signals coming from the pituitary
105
what WHO classification of anovulation is polycystic ovarian syndrome?
type 2:
| hypothalamic pituitary dysfunction
106
why is LH elevated in 60% of cases of PCOS?
the hyperinsulinaemia (caused by insulin resistance) acts as a co-gonadotrophin to LH causing increased levels
107
why is there hyperandrogenism in PCOS?
the hyperinsulinaemia (caused by insulin resistance) lowers SHBG levels, which increases free testosterone
108
compare the recommended dose of folic acid for a pregnant patient with PCOS to a pregnant patient without PCOS?
with PCOS: 5mg
| without PCOS: 400mcg
109
what are the 3 main methods of ovulation induction in PCOS?
- clomifene citrate (anti-oestrogen) + metformin
- gonadotrophin therapy
- laparoscopic ovarian diathermy (drilling)
110
what are the main 3 risks of ovulation induction?
- ovarian hyperstimulation
- multiple pregnancy
- ovarian cancer risk
111
compare monozygotic and dizygotic twins in terms of mono/di-amniotic and mono/di-chorionic possibilities?
monozygotic:
- diamniotic dichorionic
- diamniotic monochorionic
- monoamniotic monochorionic
dizygotic:
-diamniotic dichorionic
112
what does a lambda sign on ultrasound indicate?
dichorionic twins
113
what does a T sign on ultrasound indicate?
monochorionic twins
114
is twin-twin transfusion syndrome specific to monochorionic monoamniotic, monochorionic diamniotic or dichorionic diamniotic twin pregnancies?
monochorionic diamniotic twins
115
what type of imaging is best for detecting pituitary tumours?
MRI
116
do patients with ovarian failure have amenorrhoea or oligomenorrhoea?
amenorrhoea
117
what is a progesterone challenge test?
-menstural bleed in response to a 5 day course of progesterone
118
a positive progesterone challenge test suggests which hormone levels are normal?
oestrogen
119
if the progesterone challenge test is positive which WHO subtype of anovulation should be suspected?
type 2: hypothalamic pituitary dysfunction
120
if the progesterone challenge is negative which WHO subtype of anovulation should be suspected?
type 1: hypothalamic pituitary failure
type 3: ovarian failure
121
what is the definition of infertility?
failure to conceive despite regular unprotected sex over 12 months
122
compare primary and secondary infertility?
primary: couple has never conceived
secondary: couple has previously conceived
123
what is the treatment for chlamydia?
azithromycin 1g single dose
if allergic to macrolides:
doycycline 100mg BD for 7 days
124
what is the most common cause of anovulatory infertility?
polycystic ovarian syndrome
125
compare the risks of multiple pregnancy in use of clomifene citrate to gonadotrophin therapy?
risks of multiple pregnancy increases more with gonadotrophin therapy than with clomifene citrate
126
what does a hysterosalipingogram test for?
tubal patency
127
what days of the cycle can a hysterosalpingogram be done on?
1-10 days of cycle
128
when would you perform a hysteroscopy?
in cases with suspected endometrial pathology
129
when would you perform a pelvic ultrasound?
when thre is an abnormality on pelvic examination
