Female Repoductive Physioogy Flashcards
How much did the follicle grow from resting phase to pre ovulation phase?
1000 fold 0.2mm to 20mm
The granulosa cells develop a receptor for which hormone?
When do the follicle become depart on FSH to grow?
FSH
When they develop an antrum
What does LH drive in the theft cells?
Conversion of cholesterol to testosterone
Testosterone is then converted to estradiol in the graulosa cells under the inflamed of FSH
What hormone is responsible for the selection of the dominant follicle?
FSH it rises for 3 days increasing the number liber of granulosa cells meaning the production of inhibin and estadiol increase.
Negative feedback to FSH and FSH levels fall
What happens when the estradiol level increases above 300nmol/l for 2-3 days
Negative feedback switches to posited - causes LH surge
What happens to the level of estradiol after ovulation
Dramatic decrease as the thexa and granulosa layers are disrupted. As the corpus luteum form slow increase reaching peak after 1 week
What other effect does the LH surge have on the picture
Causes oocyte to complete first meiotic division with polar body leaving
Enter second meiotic diversion
When does the second meiotic division take place?
Spermatozoon penetrating oocyte
What hormone does the blastocyst form to support the corpus luteum
Human chorionic gonadotropin
What happens to the endometrium in the follicular stage under the influence of rising oestrogen
Rapid division
Glandular cells grow
Growth of blood vessels
Progesterone receptors on endometrial cells
What happens to the endometrium in the luteul phase?
Oedema
Secrete glycoproteins
Reach peak of 6mm
What is the effect of progesterone on the cervix
Reduced oedema
Mucus becomes thicker
Glycoproteins form mesh
Barrier for spermatozoa
How long is the epidermis
How long goes it take to go move down the epididymis
5 m
8-14 days
Cardiac output increases by how much
40%
When does cardiac output fall again
Lots in first 6 weeks but maybe take a several months to reach pre pregnancy level
How much does heart rate increase
10%
What changes are seen to the peripheral vascular resistance and BP?
When is nadir of BP
Reduces
SBP reduces by 10mmHg
DBP reduces by 5mmHG
24 weeks
What is supine hypotensive syndrome
Lies supine compressed inferior vena cava impeding venous return leading to fall in cardiac output,
Fall in BP feel dizzy/faint/nauseous
Fetal distress
How does the increased cardiac output change the anatomy of the heart
Hypertrophic
Dilation of the left ventricle and atrium
Raised diaphragm causes heart to be shifted anterior to the left
LAD by 15 degrees
Inverted T wave in lead 3
What changes to ventilation are seen in pregnancy? How does this affect the blood gas?
Increase in ventilation by 40% - high progesterone
Falll on PaCo2 to 4.1kPa, alkaline pH, increased bicarbonate from the kidneys
What changes causes this change in ventilation
Tidal volume increases by 40% no change in RR
Residual volume decrease/exploratory reserve/inspiraotry reserve volume
What changes are seen to the anatomy of the kidney during pregnancy?
Kidneys increase in size
Ureters dilate ( progesterone and obstruction)
Renal blood flow and GFR increase
U
How does urea and creatinine change in pregnancy?
Urea falls 4.3 to 3.1
Creatinin falls 73 to 47
Why is constipation common in pregnancy
Slower small and larger bowel motility in response to progesterone the
Why are pregnant women more likely to develop gallstones?
Drop in cholecystokinin causes decrease in gall bladder contractility
What happens to the level of alkaline phosphatase in pregnancy, why?
Increases up to 3 times
In pregnancy what change is sen to plasma volume?
Increases by 45% starting from early in pregnancy and peaks at 32 weeks.
What happens to red cell mass/haemoglobin conc/haematorcrit?
Increases red cell mass by 20-30%, rise in plasma is greater so the heamoglobin concentration and haemtocrit fall.
‘Physiological anaemia’ - most marked at 32 weeks
What happens to leucocyte count in pregnancy?
Modest rise, prilimary neutrophils
What happens to platelet count?
Debated but slightly decreases
How much more iron is needed in pregnancy?
Increase from 2.8mg/day to 6.6mg/day
What factors make pregnancy a hypercoaguable state?
Increase in coagulation factors
Decrease in fibrinolytic
Which clotting factors are increased/unchanged
Increased VII, VIII, X
Same IX and XIII
What happens to ESR and why?
Raised ESR, rise in fibrinogen
Increased coag → stop bleeding after delivery of the placenta
Does coag screening change?
No
What physiological changes are seen to the breast during pregnancy?
Which hormones cause this change?
Hyperplasia of alveolar cells and lactiferous ducts
Alveolar hypertrophy
Stimulated by proactive + human placental lactose + oestrogen + progesterone
Milk production only occurs once oestrogen + progesterone levels drop
How much milk is produced a day
500-1000ml/day
Will be tailored to baby by 3-4 weeks
What hormone stimulates prolactin production
Thyrotrophin-releasing hormone
Where is oxytocin produced/released from
Produced supraoptic and paraventricular nuclei of hypothalamus
Release from posterior pituitary gland
What is oxytocin role in breastfeeding
Binds to receptors on myoepithelial cells that allows the release of the milk
How is colostrum (early milk) differ to milk produce later?
Higher protein level relative to lactulose
High IgA
What are the constituents of breast milk?
Protein (casein (40%) + whey protein (60%)), lactose, fat , sodium, chloride
- varies between babies and is dependant on what the baby needs
What vitamins is carried in the fat of the breast milk?
A, D, E and K
Why is breast feeding so important in developing countries?
IgA is poorly absorbed an stays in GI tract, protects against diarrhoea where access to clean water is poor.
What percentage of women who are using breastfeeding as contraception will be pregnancy after 1 year?
10%
How does progesterone prevent labour
suppresses formation of myometial gap junctions
decreases effect interleukin 8 (cervical ripening)
Decreases uterine sensitivity to oxytocin
What type of drugs is mifepristone?
Antiprogesterone - cervical ripening and increased myometial activity
What causes cervical ripening?
Prostaglandins and interleukin 8 attract neutrophils to the cervix which release collagenase leading to gradual proteolysis of collagen fibres
How does myometrial contraction occur
Interaction of actin and myosin, controlled by calcium modulated protein kinase. Myometial cells communicate through gap junctions.
What changes in myometiral receptors are seen before the onset of labour
Increased oxytocin
Progesterone from type 1 to type 2
The delivery of the placenta is depends on which hormones?
Prostaglandin F2a
No changes to oxytocin
How long does it take for the endometrium take to reform?
1 week, 3 weeks at placental bed
Within 7 days halted in size
