Fertility and Conception Flashcards
What three layers does the uterus consist of?
- Thin outer layer of connective tissue
- Myometrium (thick middle layer with smooth muscle cells)
- Endometrum
What are the two parts of the ovaries?
- Thick cortex with developing follicle
2. Medulla with blood supply and nerves
What is a primordial follicle enclosed by?
- Single layer of granulosa cells
2. Basal lamina
How does a primordial follicle develop into a primary follicle and then secondary follicle??
Enlargement of oocyte
Then growth of thecal cells outside the basal lamina. Granulusa cells will start to secrete fluid that collects in a central cavity. This will finally become a tertiary follicle
What are the two primary functions of an ovary?
- Release oocyte for reproduction and menstruation
2. Hormone production for female phenotype
How many oocytes are present before birth?
7 million
What is the ovarian reserve?
Number of follicles visible in the ovary at any given time
Usually 10-20 follicles
What are the three phases of the ovarian cycle?
- Follicular phase (1-13)
- Ovulatory phase (14)
- Luteal phase (15-28)
What is the main reason for the growing follicle during the follicular phase?
Growing antrum due to secretion of fluid from the granulosa cells
What are the two main cell types of the ovaries? What hormones act on what cells?
Granulosa cells and thecal cells
- FSH acts on granulosa cells to increase AMH and oestrogen production
- LH acts on thecal cells to increase androgen production
What are the four suspensory ligaments of the uterus?
Broad ligament
Uterosacral ligament
Round ligament
Lateral ligament
What are the four main functions of the uterus?
- Transport sperm from the site of deposition to uterine tubes
- Provides a suitable environment for implantation and nourishment
- Provides mechanical protection of the foetus
- Expels the mature foetus at the end of pregnancy
What are the stages of the uterine cycle?
- Menstrual phase (1-5)
- Proliferative phase (6-14)
- Secretory phase (15-28)
What are the three parts of the uterine tube?
- Infundibulum
- Ampulla
- Isthmus
Infertility can be caused by (three mains)?
Issue with eggs
Issue with transport
Issue with implantation
In what stage are primordial oocytes arrested at birth?
Prophase 1 of meiosis 1
In what stage is the secondary oocyte arrested?
Metaphase II
When is meiosis II completed?
At fertilisation
What are 4 long-term consequences of menopause?
- Osteoporosis
- CVD
- Vaginal dryness and atrophy
- Alzheimers
What are the hormonal treatment options for menopause?
- Oestrogen (reverses symptoms of low oestrogen)
- Progesterone
- Protects endometrium
- Not required in women without uterus - Testosterone
- Increases overall energy level
- Enhances sexual desire and arousal
What are the non-hormonal treatment options for menopause?
- Lifestyle measures
- Replens
- SSRIIs
- Gabapentin
Risk of hormone replacement?
Can increase chances of breast and endometrial cancer
Benefits of hormone replacement therapy?
Can alleviate symptoms, protect bones, reduce incidence of colorectal cancer and improve quality of life
How do you diagnosis premature ovarian insufficiency?
- Women under 40
- Amenorrhoea for 4 months
- FSH > 30U/L on two occasions 6 weeks apart
What are the risks of POI?
CVD, memory loss, osteoporosis, fertility issues, death, decreased sex drive, atherosclerosis, depression
Treatment of POI?
- Hormone replacement
- Fertility treatment
- Psychological support
How does POI go over in families?
X-linked dominant inheritance
What cells line the seminiferous tubules?
Spermatogonial stem cells (lumen of tubule); for sperm production
Sertoli cells (in between stem cells, from lumenal to basal); key for nutrition
Leydig cells can be found in between tubules
What is the barrier created by sertoli cells?
Blood testes barrier
Creates luminal and interstitial compartment
How much sperm is produced every day?
120 cells
What hormones do sertoli cells secrete?
Inhibin
AMH
ABP
Growth factors
What do LH and FSH act on?
LH acts on Leydig cells to secrete more testosterone
FSH acts on sertoli cells to simulate sperm development
Describe the acrosome reaction?
- Triggered by sperm coming in contact with oocyte
- Interaction with ZP3 protein on oocyte membrane
- Leads to exposure of hyaluronidase and acrosin enzymes
- Facilitates oocyte penetration
Describe oocyte activation?
Release of cortical granules, blocks polyspermic penetration
Resumption of meiosis
Formation of male and female pronuclei
What factors can affect sperm?
- Anabolic abuse
- Environment
- Radiation
- Air pollution
- Food chain pollution
How prevalent is infertility?
1/7 couples
What is the most significant predictor of infertility?
Woman’s age
What are the 4 steps os assessing infertility in couples?
- History
- Basic investigations
- Semen analysis
- Assessment of pelvic anatomy and fallopian tube potency
What are the three classes of ovulatory disorder:
- Group I; hypothalamic amenorrhoea or hypogonadotrophic hypogonadism
- Group II; HP-ovarian dysfunction
- Ovarian insufficiency
What is PCOS?
Polycystic ovarian syndrome
What are the main symptoms of PCOS?
- Irregular periods
- Excess androgens, causing facial or body hair
- Polycystic ovaries – your ovaries become enlarged and contain many fluid-filled sacs (follicles) that surround the eggs
What are the three treatment options for PCOS?
- Clominphene citrate
- Letrozole
- Gonadotrophins
What are the three germlayers?
- Endoderm
- Mesoderm
- Ectoderm
What does the endoderm form (2)
Epidermis
NS
What does the mesoderm form? (6)
Skeleton Muscle Dermis Kidney Blood Reproductive system
What does the ectoderm form? (5)
Gut Liver Pancreas Lungs Endocrine glands
What is the first organ to become functional?
Heart
What does the neural crest arise from?
Neural tube (ectoderm derivative)
What is azoospermia?
Lack of sperm in semen
Non-obstructive (primary) vs obstructive (secondary)
What are causes of primary azoospermia?
Impaired spermatogenesis, due to hypopituitarism, hyperprolactinemia, exogenous testosterone, chemotherapy, Klinefelter, cryptorchidism, Sertoli cell-only syndrome, orchitis, trauma, radiation
Spermatogenesis - decreased
Size of testes - small
FSH level - raised
What does the wolffian duct become in men?
internal reproductive organs
Testosterone from testis causes development of Wolffian duct into the epididymis, vas deferens and seminal vesicles
What does the wolffian duct become in women?
Absence of AMH causes regression of the Wolffian duct
What does the Mullerian duct become in men?
AMH from testis causes regression of the Mullerian duct
What does the Mullerian duct become in women?
Mullerian duct persists, becoming the female internal reproductive organs
Oestrogen from ovaries causes development of Mullerian duct into the fallopian tubes, uterus and upper vagina.
Absence of testosterone leads to development of female external genitalia
What does the SRY gene cause?
Development of testes
What is the risk of Chorionic villus sampling?
Miscarriage ( higher rate of miscarriage than amniocentesis)
Chorionic villus sampling can be performed weeks 11-14, whereas amniocentesis can be performed 15+ weeks.
Define gastrulation?
During the development of the embryo A blastula (single layer of cells) develops into a gastrula, ultimately leading to the development of the ectoderm, mesoderm and endoderm.
Define the puerperium
Time from delivery of placenta until the body returns to the pre-pregnant state ~6-8 weeks.
Here the uterus shrinks from being palpable around the umbilicus to being unpalpable after a few weeks.
Goes from weighing 1kg just after birth, to weighing 50-100g after 6-8 weeks.
How would you define infertility?
A woman of reproductive age who has not conceived after 1 year of unprotected sexual intercourse
What is a Robertsonian translocation?
fusion of two acrocentric chromosomes leading to loss of the short arms of both chromosomes and thus a fusion chromosome is produced (less common)
What is a Reciprocal translocation?
exchange of material between two non-homologous chromosomes (more common).
What are the features of Trisomy 13 (Patau)?
Learning difficult - severe Dysmorphic features - Cleft lip/palate, holoprocencephaly, postaxial polydactlyl Organ defects - renal and cardiac Frequency - 1:5000 live births Frequency @ maternal age 43 - 1:1100
45% die within 1 month
85% within 1 year
What are the features of Trisomy 18 (Edwards)?
Learning difficulty - severe Dysmorphic features - Micrognathia, prominent occiput, clenched overlapping fingers, Rocker-bottom feet Organ defects - cardiac Frequency - 1:3000 live births Frequency @ maternal age 43 - 1:500
Micrognathia - small lower jaw
Rocker bottom feet
30% die within 1 month
90% within 1 year
What are the features of Trisomy 21?
Learning difficult - mild to moderate
Dysmorphic features - Flat nasal bridge, upslanting palpebral fissures, epicanthal folds, protruding tongue, single palmer crease, clinodactyly, sandal gap
Organ defects - cardio, usually AV septal defect
Frequency - 1:700 live births
Frequency @ maternal age 43 - 1:50 live births
Clinodactyly - palmar curvature of a finger or digit
Sandal gap - as if you were wearing sandals, space between big toe and 2nd
What are the two main functions of oxytocin?
Two main functions of the hormone oxytocin are milk ejection and uterine myometrial contraction.
