Repro Physiology Flashcards
What occurs in the ovaries?
Contain ovarian follicles-oogenesis-release of mature egg
What happens in the fallopian tubes?
Egg pick up happens & fertilisation occurs
What is the structure of the ovaries and what are these 3 layers made up of?
Surface- connective tissue capsule covered with layer of simple cuboidal epithelium
Cortex- peripheral part, connective tissue containing ovarian follicles (one oocyte surrounded by single layer of cells)-Primordial follicle pool=makes up egg reserve
Medulla- central part, connective tissue with blood vessels
What are the functions of the ovaries?
- Oocyte production
- Steroid hormone production (oestrogen & Progesterone & Testosterone)
How many eggs are released per menstrual cycle & how many are ovulates during life?
One mature egg per menstrual cycle, around 400 ovulated during entire reproductive lifespan (Ovarian reserve is fixed & thought to be determined at birth)
Majority of eggs perish during the cycle
Is there an infinite number of eggs?
NO, finite number of eggs, declines with increasing age (starts ~30 years old)
What are the roles of:
1. Oestrogen
2. Progesterone
3. Testosterone?
- Develops female secondary sexual characters
- Prepares endometrium for implantation
- Has important functions of maintaining the female sexual function (50% of testosterone produced by ovaries before menopause)
When does primordial germ cell mitosis occur?
In foetal life only
Until when are primordial follicles arrested in the stage of first meiotic division?
Until puberty
First meiotic division complete & second division starts after puberty: This leads to what?
Release of one secondary oocyte in a menstrual cycle which is capable of fertilisation
When does second meiotic division completes?
After fertilisation of oocyte with sperm
Germ cells (oogonia) mitotically divide into what?
Primordial germ cells
What is the normal complement of chromosomes in any human cells?
46 chromosomes
How many follicles are selected?
Only dominant follicle selected & will ovulate- rest will perish
What is the difference between primordial follicles & primary follicle?
Primordial follicles- primary oocyte arrested in first meiotic division surrounded by one layer of squamous pre granulosa cells.
Primary follicle- oocyte surrounded by zona and cuboidal granulosa cells
What is the secondary follicle?
Secondary follicle- increased oocyte diameter and multiple layer of granulosa cells, resumption of first meiotic division
What is the tertiary/Graffian folliclE?
Follicular fluid between the cells which coalesce to form antrum, completion of first meiotic division to form secondary oocyte and start of second meiotic division.
What is antrum & what is secondary oocyte & follicle?
Antrum=fluid filled space surrounding the egg
Follicle=Layer of cells containing the egg
Secondary oocyte=mature egg
What is the endocrine control of female reproductive axis called?
Hypothalamic-pituitary-ovarian axis
Hormone release controls what in the ovary & uterus?
Ovarian cycles within the ovary & the menstrual cycle within the uterus
Positive feedback only helps mid cycle: What is this responsible for?
Responsible for ovulation
Endometrium is ..?.. in the first day of menstruation because of ..?..
THIN
BLEEDING
What is decidualisation?
Changes to the endometrium in prep for pregnancy
What does oestrogen do to the endometrium?
Causes thickening of the endometrium
What does progesterone secretion do to the endometrium?
Causes changes in blood vessels within the endometrium & also adds to the thickness & increases secretory changes in the endometrium
What happens at the end of the 28 days if pregnancy does not result?
Menstruation sets in and a new cycle starts
What is the process of sperm production called?
Spermatogenesis
Why is testicular temp<body temp?
To facilitate sperm production
What is the role of the epididymis?
Storage site for sperm (remains there for ~3 months)
What structures are responsible for semen production?
Seminal vesicles & prostate create the fluid (that mixes with sperm in the urethra)
What is the fibrous capsule around the testis called?
Tunica Albuginea
Where is the site of sperm production?
Seminiferous Tubules
What can generally change during pregnancy?
Mechanical
Metabolism-anabolic then quickly becomes catabolic to allow nutrient supply to foetus
Fatigue – particularly early pregnancy
Heartburn/reflux
Oedema
Breasts
Thyroid
General state of immunosuppression
Weight gain
Insulin resistance- almost 2 x increase in insulin
Triglyceride breakdown increases- can get starvation Ketoacidosis – within 24-48 hrs can become very acidotic when pregnant and this happens
DKA very dangerous in preg can result in IUD
BMR doubles in preg
What is gestational diabetes?
Gestational diabetes=insulin resistance & hyperglycaemia of pregnancy – more likely to develop T2DM (should be checked once a year-mitigate risk with lifestyle factors)
Do you get oedema in pregnancy?
70-80% get oedema- physiological mostly but can be indicative of pathology such as pre-eclampsia (High BP, oedema & proteinuria)
What significant changes occur in the first trimester in the cardiovascular system?
Increased circulating BV-50-70%
SVR falls – maximal at 20-32 wks
Increased blood flow
Increased CO (40%), SV increases (SVxHR= CO)
Increased HR
In supine position – 25% reduction in CO
Increased O2 consumption
Prostacyclins –systemic vascular resistance
..1.. tends to drop in middle trimester & then rise-those who don’t drop are more inclined to be the ones to have ..2..
1) BP
2) pre-eclampsia
What are the intrapartum CV changes that occur?
Autotransfusion of contractions
Pain – increasing catecholamines
CO increases by 10% in labour and by 80% in 1st post delivery hr
What are the postpartum CV changes that occur (BV, BP, SVR, HR & CO)?
Return to normal by 3 mths (mostly)
Blood volume decreases by 10% 3 days post delivery
BP initially falls then increases again days 3-7(pre preg levels by 6 wks)
SVR increase over first 2 wks to 30% above delivery levels
HR returns to pre preg over 2 weeks
CO increases by up to 80% 1st hr post delivery then continues to fall over the next 24 weeks
What are the respiratory changes that occur?
Significant increase in oxygen demand (20%)
40-50% increase in minute ventilation
Increased respiratory rate
Increased tidal volume
Decreased functional residual capacity
PEFR and FEV1 unchanged
PCO2 ↓
Placenta is foetus’s resp system
Diaphragm moves up & thoracic circumference increases- May get splaying of lower ribs
Acid base balance changes-CO2 will be increased & PO2 tends to sit higher
02Hg dissociation curve shifts to the right- decreased affinity for oxygen
Where is the dramatic dilation of the urinary collecting system more pronounced?
On the RIGHT
What are some renal system changes ?
Increased renal plasma flow – 60-80% by end of second trimester
GFR ↑ and creatinine clearance increases by up to 50%
Protein excretion increased
Microscopic haematuria may be present
80% women develop oedema
Glycosuria common
Urate ↑ with increasing gestation
Urea ↓, creatinine ↓
Microscopic haematuria can be the result of progesterone
Urethra shortens so more risk of UTI also harder to empty bladder as easily
What does plasma volume increase in relation to?
Birthweight
What are the haematological changes that occur in preg?
↓ hg, hcrit, rcc
↓ platelet count
2-3 fold increase in requirement for iron
WCC increases
Hypercoaguable
No change MCV nor MCHC
What does folic acid reduce the risk of?
Conditions like spina bifida
(10 -20 fold increase in folate requirements in preg)
