WEEK 1 Flashcards
What are the functions used to catagorise maternal adaptions in pregnancy?
- increased availability of precursors for hormone
production and fetal–placental metabolism; - improved transport capacity;
- maternal–fetal exchange; and
- removal of additional waste products.
what are the 4 pelvis types?
Gynaecoid
Android
Anthropoid
Platypeloid
what are the 4 stages of mentstration?
Mensus
Follicular
Ovulation
Luteal
what is the average age for onset and cessation of the menstrual cycle
onset= 12-15 cessation = 45-55
When does ovulation occur in the cycle?
about half way through
when egg is released from mature follicle to ovaries
What is the egg called?
Gamete (haploid cell)
what is fertilisation?
- involves the combination of 2 haploid cells into a single diploid cell (called a zygote)
what is a zygote?
a cell with a full set of chromosomes
how long after fertilisation does implantation occur?
approx 6 days
when does the placenta begin to form?
2nd week of gestation
- fully established by week 8-10
- full size by month 4
when does the placenta become the main site of hormone production in pregnancy?
Week 8-10
prior it’s the corpus leutie?
where does diffusion occur in the placenta?
Intervillious space
what are some transport functions of the placenta?
Transport
- Resp gas movement
- nutrients
- hormones
- waste products
what are some immunologic functions of the placenta?
Immunologic
- barrier against larger bacteria
- some maternal antibodies cross through
what are some endocrine functions of the placenta?
oestrogens
progesterone
what are some metabolic functions of the placenta?
synthesise glycogen, cholesterol, fatty acids and enzymes
When. is the placenta really thin, increasing risk of diffusion of toxins
30-35 weeks
what do you need to consider with pregnancy and house fires?
carbon monoxide diffuses across placenta easier than O2
how does foetal circulation differ from normal circulation?
- deoxygenated blood leave foetus through arteries (goes from baby to placenta)
- oxygenated blood enters through veins (from placenta to baby through umbillical vein)
What is foetal blood flow?
500ml/min
what are the 2 membranes in the placenta?
- Chorion (outer)
- Amnion (inner)
what stops the 2 placental membranes from fusing?
amnionic fluid (2ml)
what is amnionic fluid made of?
98% water
2% glucose, protein, sodium, urea & creatine
How much fluid makes up the amnionic fluid?
500ml - 1500ml
replenishes itself every 3 hours
what are the functions of the amnionic fluid?
- equalise pressure around the foetus
- cushions foetus from external compression
- Provides constant temp
- provides fluid for the foetus to swallow
- allows freedom of movement for the foetus
- lubricates the membranes and the foetus
what does the umbilical cord do?
provides a circulatory connection between mum and baby
what is the umbilical cord made of?
Wharton’s jelly
what are the 3 trimesters of pregnancy?
1st - conception - 13 weeks
2nd - 13 weeks - 26 weeks
3rd - 26 weeks until birth
where is progesterone produced?
corpus luteum until about week 10 then the placenta
what does progesterone do?
prepares uterus for implantation
what does progesterone do with immune responses?
suppresses maternal immunologic response to fetal antigens
what does progesterone do to smooth muscle?
decreases contractility
how does progesterone effect lactation?
it inhibits it
What does oestrogen do?
stimulates female secondary sex characteristics:
- breast growth
- uterine growth
- vaginal wall thickening
- vaginal lubrication
Increased coagulability
Decreased bowel mobility
when is oestrogen released during pregnancy?
Released from placenta during pregnancy
What does Beta Human Chorionic Gonadotropin do?
- stimulates corpus luteum to continue releasing hormones
- allows pregnancy to establish and continue without menses occuring
When is Beta Human Chorionic Gonadotropin released?
from the blastocyst on implantation into the uterine wall
what are the hormonal physiological changes of pregnancy?
increased progesterone, oestrogen, HCG & HPL
what are the mechanical physiological changes of pregnancy?
increased metabolic demand
what are the foetal/uterus/placental and mother physiological changes of pregnancy?
placenta circulation
- low-pressure arteriovenous shunt
what happens to the uterus during pregnancy
- increases in size from 60g to 1kg
- oestrogen stimulates muscle cell hypertrophy
- capacity increases from 10m to 5L
- all 3 layers of smooth muscle increase
what happens to the cervix during pregnancy
- cell number increases due to oestrogen
- secretes thick, sticky mucous plug
- softens during labour (Goodell’s sign)
What are the cardiovascular changes in pregnancy
- decreased peripheral vascular resistance
- decreased pulmonary vascular resistance
- decreased colloid oncotic pressure
- increased cardiac output
- increased HR
how does the heart vol change in pregnancy?
increases from 70ml - 80ml
Apex of heart moves to where during pregnancy
from the 5th intercostal space to the 4th
how does the blood volume change?
increases from by 30-50%
how does the red cell volume change?
increase by 18-20%
how does the plasma volume change?
increase by 50%
How far does the diaphragm rise?
4cm
what happens to o2 consumption?
increases by 15%
What happens to CO2 and PO2?
co2 decreases from 35-45 to 30mmHg
Increased o2
how much does inspiratory reserve change by?
increases by 300mL
how much does expiratory reserve change by?
decreased by 200ml
how much does tidal volume change?
from 500 to 700ml
