Unit 7 Week 1: Conception Flashcards
causes of male infertility
hormone imbalance
genetic problems
undescended testicles
tubule defects
STI’s and inflammation
varicoses
prior surgeries
overheating testicles
excessive alcohol, smoking and illegal drugs
obesity
medications
increased scrotum temp
testicular cancer
congenital defects
testicular injury
premature ejaculation
delayed ejaculation
retrograde ejaculation
hormone imbalance male infertility
hypogonadism
decreased sperm production
genetic problems male infertility
klinefelter syndrome: males for with extra X chromosome
leader to decreased testosterone
decreased size testicles
no sperm production
undescended testicles male infertility
increased temperature on abdomen
decreased sperm quality and production
STI’s and inflammation male infertility
prostatitis
epididymitis
orchitis
prior surgeries male infertility
vasectomy/ surgeries in genital regions
obesity male infertility
high amounts of fatty tissues in surround regions will increase temperature
which medications can cause male infertility
testosterone replacement
long term anabolic steroid use
chemotherapy
some antibiotics/ anti-depressants
increased scrotum temperature male infertility
abnormal sperm motility and shape
premature ejaculation
before vaginal penetration
delayed ejaculation
may be unable to ejaculate
retrograde ejaculation
semen to bladder instead of urethra
what is varicoceles
abnormal swelling of veins in pampniform plexus (transport deoxygenated blood away from the testicles)
pampniform plexus drains to testicular vein
resistance in these veins leads to back flow of deoxygenated blood
can cause infertility by increasing temperature of testicles as blood is pooling/ testicular atrophy
varicoceles is more common on which side
left side as drains to renal vein
increased vein length so increased resistance
right Side drains to inferior vena cava
symptoms of varicoceles
pain/ discomfort
reduced fertility
may have no symptoms
presentation of varicoceles
scrotal mass, may feel like a bag of worms
more prominent when standing but may disappear when lying down
testicular asymmetry but this is also present in healthy individuals
how should you respond if swelling doesnt go away in suspected varicoceles
when lying down if the swelling doesnt go away it may indicate retroperitoneal tumours that are obstructing drainage of renal vein
needs urgent urology referral
testing for varicoceles
ultrasound
blood tests for FSH and testosterone
semen analysis
varicoceles treatment
painkillers if needed
surgery: only if pain, testicular atrophy or reduced fertility
investigations for male infertility
most cases are of unknown aetiology
diagnosed if abnormal semen parameters in 2 semen analysis tests separated by one month
different investigations include:
medical history
physical exam
urinanalaysis
semen analysis
hormonal tests
semen analysis
tests the health and viability of the sperm
measures: number, shape, motility, ph, ouse, liquefaction, appearance
tested 7 days apart and over course of 2-3 months, average gives the most conclusive result
to get a good sample: semen at body temperature, too warm or too cold is inaccurate
physical examination male infertility
look at penis, prostate, testes and scrotum
testes may have lumps or deformities
penis: shape structure any obvious abnormalities
results of semen analysis
what affects sperm count
alcohol
caffeine
herbs
prescription drugs
recreational drug use
tobacco
urinalysis male infertility
can indicate presence of infection
hormonal tests male infertility
evaluate testosterone and FSH levels
any further testing that may be used in male infertility
seminal fructose test
post-ejaculate urinanalysis
semen leukocyte analysis
Kruger and WHO morphology
anti-sperm antibodies test
sperm penetration assay
scrotal and transrectal ultrasound
testicular biopsy
vasography
genetic testing
specialised sperm function test
sperm plasma membrane
chlamydia test
causes of female infertility
hypothyroidism
premature ovarian failure
scarring from surgery
cervical mucus problems
fibroids
endometriosis
pelvic inflammatory diseases
polycystic ovary syndromw
hypothyroidism female infertility
decreased thyroxine
causes decreased FSH and LH secretion
menstrual cycle won’t be regulated
follicles won’t be stimulated in growth
prematur ovarian failure female infertility
where ovaries stop working in age under 40
sometimes runs in families
scarring from surgery female infertility
pelvic surgery can scar/ damage fallopian tubes
cervical surgery may scar/ shorten cervix
which may cause premature birth
cervical mucus problems female infertility
when ovulating it will thin so sperm can swim easier
problems with mucus then conception may be harder
fibroids female infertility
benign growths in/around the womb
may prevent fertilised egg implanting/ may block fallopian tubes
endometriosis female infertility
tissue similar to womb lining grows elsewhere e.g. ovaries, fallopian tubes and can cause blockages
surgery can help improve chances of pregnancy
pelvic inflammatory diseases female infertility
womb inflammation/ fallopian tubes/ ovaries
often caused by STI’s
polycystic ovary syndrome female infertility
ovaries produce excessive androgens (testosterone)
can cause imbalance in reproductive hormones
causing irregular periods
small follicle cyst on ovaries due to lack of ovulation
insulin resistance= androgen production
investigations female infertility
hormone testing
hormone level testing
imaging tests
ovarian reserve testing
pregnancy testing
hormone level testing female infertility
blood tests done on specific days of the menstrual cycle
hormone imbalance will affect ovulation and fertility
hormones that are tested:
progesterone
LH
FSH
estradiol
progesterone levels female infertility
low levels= corpus leuteum impaired function
high levels aren’t concerning
LH levels female infertility
low levels= problem with hypothalamus/ ovulation
high levels= PCOS, POF
FSH levels female infertility
low levels= decreased ovarian function
high levels= problems with pituitary/ hypothalamus
estradiol levels female infertility
low levels= problems with hypothalamus
high levels= problems with ovaries e.g. tumour or cyst
which imaging tests are done to investigate female infertility
ultrasound
hysterosalpingography
laparoscopy
ultrasound female infertility
analyse fluid as it passes through fallopian tubes
checks for any abnormalities of blockages
hysterosalingography female infertility
specialised x rat to view inside of uterus and fallopian tubes
thin tube threaded through the vagina and cervix
contrast material injected into the uterus, series of x rays follow dye into the tubes
outlining the shape of the uterus and fallopian tubes
laparoscopy female infertility
minimally invasive surgical technique where telescopic like instrument with light and camera are inserted into the abdomen through a small incision
ovarian reserve testing female infertility
determines woman’s remaining egg supply quality and quantity and can be done by measuring:
1. day 2 or 3 FSH levels: elevated FSH= diminished egg supply
2. AMH testing (anti-mullerian hormone): higher= higher egg supple or immature follicles in ovaries
3. antra follicle count: using ultrasound you can count women’s follicles
pregnancy testing female infertility
check urine/ blood for hormone HCG (human chorionic gonadotrophin)
HCG is produced after fertilised egg attaches to uterus wall
normally 6 days after fertilisation
if HCG rises rapidly, doubles every 2/3 days
anything 25mlU/ml considered positive and less than 5 negative
false positives: taking test too soon after fertility medicine/ ovary problems/ menopause
false negatives: test too early, test result too soon, time of day as urine is most concentrated in the morning
qualitative HCG
binary yes or no
quantitative HCG
tells you the exact HCG content in the blood
IVF eligibility
women under 40 should be offered 3 cycles of IVF on the NHS if:
trying to get pregnant through regular unprotected sex for 2 years
not been able to get pregnant after 12 cycles of artificial insemination, at least 6 of these using intrauterine insemination (IVI)
if you have been 40 during the cycle, complete the cycle but no further cycles are offered
if IVF is only likely treatment then refer straight away
all women aged 40-42 offered 1 cycle if the NICE criteria are met
different types of oral contraceptives
combined pill
progestin only pill
emergency contraceptive pill
combined pill
also contains oestrogen
progestin only pill
emergency contraceptive pill
different types of non-oral contraceptives
implant
IUD/ copper coil
injection
patch
vaginal ring
diaphragm/ cap
condoms: internal and external
fertility awareness
withdrawal method
female sterilisation
male sterilisation
IUS/ hormonal coil
injection
patch
external condoms
withdrawal method
female sterilisation
male sterilisation
fertility awareness
IUS
IUD
internal condoms
vaginal ring
diaphragm/cap
what could be done to increase chances of conception
stop smoking
maintain a healthy weight
reduce OH intake
intercourse every 2-3 days out of 7
intercourse around ovulation
loose fitting clothing?
avoid vaginal lubricants
ovulation predictors
detects rise in LH
rise in LH signals egg release
darker line than control line
ovulation in the middle of the cycle
LH peaks 12 hours before ovulation
positive reading you should expect to ovulate 12-36 hours after
take multiple times a day
false positive= PCOS
what are the 4 main hormones involved in the mestrual cycle
oestrogen
progesterone
follicle stimulating hormone FSH
leutenising hormone LH
FSH function
stimulates follicle development
LH function
causes ovulation
oestrogen function
steroid sex hormone that acts on tissues with oestrogen receptors to promote female characteristics: develop breast tissue, vulva, vagina, uterus, endometrium, thin cervical mucus to allow sperm penetration, causes negative feedback to decrease FSH and LH
progesterone function
steroid sex hormone
if pregnancy occurs then placenta takes over at 5 to 10 weeks
acts on tissues already acted on by oestrogen: thicken and maintain endometrium, thickens cervical mucus and causes rise in body temperature
what are the 2 phases of the menstrual cycle
follicular phase and luteal phase
follicular phase can vary in days but normally 14 days
luteal always 14
follicular phase
hypothalamus releases gonadotrophin releasing hormone
causes FSH release and LH release from anterior pituitary
in ovaries there are a finite number of primordial follicles
FSH stimulates around 15-20 follicles to develop once a month
as follicles develop the granulosa cells surrounding them will secrete oestrogen
before ovulation there is a decrease in oestrogen and increase in LH
causes one follicle to reach ovary surface and release the ovum
ovulation occurs at day 14
luteal phase
follicle that released ovum collapses and becomes corpus luteum
corpus luteum secretes high levels of progesterone and some oestrogen
if the egg is fertilised will secrete HCG, maintaining corpus leuteum
if the ovum isn’t fertilised then the corpus leuteum will degenerate, stops producing oestrogen and progesterone
removes negative feedback of FSH and LH so FSH begins to increase and cycle begins
lack of production of oestrogen and progesterone will cause breakdown of endometrium
causing menstruation
menstruation
cycle day 1
superficial and middle layers separate from basal layers of endometrium
tissue breaks down inside of the uterus
released from the cervix to the vagina
fluid containing blood will then release from the vagina lasting 1-8 days= period
what does hypothalamus secrete menstruation
gonadotrophin releasing hormone
what does the anterior pituitary secrete menstruation
FSH
LH
what do the follicles in the ovaries secrete menstruation
oestrogen
what does the corpus leuteum secrete menstruation
progesterone and oestrogen
what does the embryo secrete menstruation
human chorionic gonadotrophin (HCG)
6 stages of fertilisation
sperm transport
sperm capacitation
sperm-oocyte interaction
sperm-oocyte fusion
completion of meiosis 2
zygote formation and implantation
transport of sperm
vagina: where ejaculate is deposited, coagulates to form alkaline loose gel to protect against vaginal acidity and immunological response
cervix: cervical mucus and high levels of oestrogen cause sperm to change microstructure of mucus= easy passage
uterus: uterine contractions to propel sperm to uterus
sperm capacitation
epithelial interactions between sperm and uterine wall will destabilise plasma membrane of the sperm
acrosomal reaction occurs:
glycoprotein coat covering acrosome is removed
sperm plasma and acrosomal membrane fuse
enzyme released from acrosome (acrosin, hyaluronidase, hexasaminidase)
increase in Cat Per channels in flagellum, Ca2+ influx and sperm motility hyper activated
sperm-oocyte interactions
corona radiata: capacitated sperm pass through hyaluronidase dissolves hyaluronic acid cementing corona radiata cells
zona pellucida: sperm penetrate here due to across released from acrosome, made up of 4 main glycoproteins ZP1-4
ZP3 are the only ones that bind to the receptors on the surface of human sperm
sperm-oocyte fusion
cortical reaction: sperm fuses with the cell membrane of the oocyte
triggers increase in Ca2+ in eggs cytosol
causes release of lysosomal enzymes in cortical granules
initiate zona reaction= slow polyspermy block as cortical granules harden the oocyte membrane
release of hydrolytic enzymes further degrade the zona pellucida
stimulates exocytosis of cortical granules to harden the oocyte membrane, impenetrable to further sperm
completion of meiosis 2
oocyte completes myosis 2
forms definitive ovum and polar body
polar body is degrades
zygote formation and implantation
pronucleus of ovum and pronucleus of sperm fuse to form zygote
zygote divides by mitosis in fallopian tubes
day 3-4= morula 16 cells
5= blastocyst
7/8= implantation, blastocyst burrows into uterine lining
define different sperm parameters
