14 Maternal Problems In Pregnancy

Front 1

name 3 effects of progesterone in pregnancy

Back 1

1) endometrium - secretory changes
2) breasts - tender/sore
3) GIT - nausea/vomiting/constipation

Front 2

name symptoms of pregnancy. what are most of these due to?

Back 2

nausea
constipation
lethargy
breast tenderness
haemorrhoids
varicose veins
oedema
backache
flushes

due to progesterone

Front 3

when is hCG detectable in pregnancy?

Back 3

within 6-7 days after fertilisation

Front 4

when does the placenta take over endocrine function from the corpus luteum?

Back 4

after 1st trimester

Front 5

Outline maternal cardiovascular changes in pregnancy

Back 5

- maternal vascular-neogenesis, accommodated by changes in function of baro- & volume receptors
- increased blood flow to breasts, kidneys & GIT (increased metabolism)
- plasma volume increases
- TPR falls (vasodilation)
- increased CO 40% by term due to increased stroke volume
- mean BP remains the same, rises towards term
- HR increases 15%

Front 6

explain what the increased stroke volume in pregnancy is due to (3)

Back 6

- increase in ventricular wall muscle mass
- increased end-diastolic volume
- heart physiologically dilated with increased contractility

Front 7

How is mean BP maintained during pregnancy?

Back 7

increased SV increases systolic BP
but increased flow into additional tissue reduces the diastolic BP
maintains mean BP

Front 8

What changes in a pregnant woman's heart might be apparent on examination?

Back 8

upward displacement
mild hypertrophy
flow murmers

Front 9

Describe supine hypotension in pregnancy & how can it be avoided?

Back 9

aortocaval compression by gravid uterus
reduces venous return
reduces CO
reduces BP

use a left lateral position or wedge/tilt

Front 10

What cardiovascular changes occur during labour?

Back 10

- further increase in CO
- contractions lead to autotransfusion of blood back into the circulation
- sympathetic response to pain increase HR & BP
- CO increased during & between contractions

Front 11

What cardiovascular changes occur after delivery?

Back 11

immediate rise in BP due to alleviation of IVC compression & contraction of uterus
CO increases 80%
back to non-pregnant levels within an hour

Front 12

Describe BP changes in pregnancy

Back 12

1st half: reduced diastolic, little change systolic - wider pulse pressure
2nd half: changes reverse

BP falls from end of first trimester (fall in TPR) but rises in late pregnancy

Front 13

Summary of cardiac changes table

Back 13

Front 14

What would make you suspect pre-eclampsia?

Back 14

high BP
proteinuria
oedema

can lead to eclampsia = seizures

Front 15

what is the threshold BP for hypertension in pregnancy?

Back 15

140/90

Front 16

What tests might indicate pre-eclampsia?

Back 16

24 hour urine protein - proteins
platelets - low
urinanalysis - urate indicates renal dysfunction
liver function tests

Front 17

what should be done if pre-eclampsia is suspected?

Back 17

IV hydralazine (vasodilator, reduces BP)
IV magnesium sulphate (reduces cerebral irritability, vasospasm & prevents fits)
emergency C-section (only cure is to remove baby)

Front 18

name underlying conditions which may lead to pre-eclampsia?

Back 18

essential hypertension
underlying renal diseases (associated with proteinuria)
phaeochromocytoma (tumour of adrenal medulla)

Front 19

name & explain iron deficiency anaemia experienced in pregnancy

Back 19

- foetus requires high nutrition flow in 2nd trimester
- discrepancy between plasma vol expansion & red cell mass expansion
- maternal Hb levels fall = dilutional/physiological anaemia
- 1g of iron is needed in pregnancy
- eventually higher Hb flow is required by foetus & erythropoietin stimulation increases red cell mass

Front 20

Except increasing nutritional/O2 demand from the foetus, how else is iron turnover changed in pregnancy?

Back 20

menstrual losses have stopped

Front 21

How will smoking affect O2 flow to the foetus & by what mechanism

Back 21

carbon monoxide in maternal blood flow
Hb-O2 curve shifts left = Bohr shift
foetus suffers reduced pO2 in extracting its O2 requirement, which may not be fulfilled

Front 22

how may mean arterial BP change in pregnancy & what symptoms might the mother experience?

Back 22

- rising progesterone levels causes peripheral vasodilation
- reduces TPR
- compensated by increased CO
symptoms: hot flushes, sweat, nasal congestion

Front 23

What 3 factors contribute to venous distension & engorgement in late pregnancy?

Back 23

- smooth muscle relaxation due to progesterone
- raised circulating blood volume & low resistance to flow through the foetal-placental unit create high venous pressure
- mechanical pressure from the uterus compresses the IVC, which may increase lower limb venous pressure, but only when mother is supine

Front 24

what are 2 long-term sequelae attributed to venous distension & engorgement in late pregnancy?

Back 24

varicose veins
haemorrhoids

Front 25

what happens to resp rate, tidal volume & oxygen uptake in pregnancy?

Back 25

RR - little change
tidal vol & O2 uptake increase

Front 26

why might dyspnoea be experienced in pregnancy?

Back 26

- increased awareness of desire to breathe
- increase in tidal volume lowers the pCO2
- blood shunted away from functioning alveoli
Increased resp effort & reduction in pCO2 induced by progesterone acting directly on the resp centre & sensitising chemoreceptors to CO2 changes

Front 27

what happens to the minute ventilation in pregnancy?

Back 27

increases 40-50%, mainly due to increase in tidal vol as RR remains essentially unchanged

Front 28

what anatomical/mechanical effect will the expanding uterus have on the resp system?

Back 28

diaphragm rises & intercostal angle widens to due uterus exerting a mechanical limitation to inspiration
- reduced functional residual capacity
- no change in vital capacity: FEV1 & peak flow are unchanged

Front 29

how much will the following change during pregnancy:
CO
HR
O2 consumption
tidal volume

Back 29

CO - increases 40%
HR - increases to 80-90bpm
O2 consumption - increases 15%
tidal volume - increases 40%

Front 30

Describe maternal arterial blood gases in pregnancy

Back 30

pO2 increases
pCO2 decreases 15-20%
compensatory fall in serum HCO3-
mildly compensation resp alkalosis - maternal pH 7.44

Front 31

Summary of resp changes table

Back 31

Front 32

Describe the advantage of increased tidal volume in O2 transfer to the foetus (3)

Back 32

Enhanced gas transfer:
- pCO2 reduced 15-20% while pO2 much the same
- this is offset by increased 2.3 DPG in maternal RBCs: shifts dissociation curve to right so that maternal O2 saturation changes little
- this enhances O2 transfer to foetal RBCs which have dissociation curve shifted to the left: foetal Hb much higher affinity for O2 & less sensitive to 2,3 DPG

Front 33

What happens to women with chronic respiratory diseases in pregnancy?

Back 33

tend to deteriorate less - functional changes facilitate airflow along bronchial tree, & FEV1 & PEF don't change

in severe asthma, deterioration may be due to cessation of medicine

Front 34

Name 2 ways progesterone acts to change ventilation

Back 34

- acts directly on respiratory centre
- increases carbonic anhydrase in maternal RBCs, so increases breakdown of CO2 & excretion of HCO3- through maternal kidneys

Front 35

What are the 2 main renal changes in pregnancy?

Back 35

- increase in renal blood flow (GFR)
- fall in urea & uric acid in early pregnancy

Front 36

What effects might the gravid uterus have on the ureters?

Back 36

- compresses them above the pelvic brim
- increased intraureteral tone
- ureteral dilatation
- hydroureter
- hydronephrosis
May also be caused by smooth muscle relaxation effect of progesterone.

Front 37

Explain why urinary incontinence could occur in pregnancy

Back 37

- pressure on the bladder from enlarged uterus
- engagement of foetal head towards the end of pregnancy

Front 38

What complications are associated with multiple pregnancies?

Back 38

- increased incidence of pregnancy-induced hypertension
- anaemia
- polyhydraminos
- perinatal mortality
- antepartum haemorrhage

Front 39

What compensates for the increased expected sodium loss in pregnancy, due to a raised GFR?

Back 39

increased secretion of renin, aldosterone & angiotensin II

Front 40

what might progesterone-induced ureteric dilatation & slowed urine transport increase the risk of?

Back 40

- UTI
- loin pain due to hydronephrosis & pyelonephritis(secondary to progesterone & mechanical obstruction of ureter by uterus)

Front 41

What are the effects of diabetes on pregnancy?

Back 41

miscarriage
foetal malformations
IUGR
macrosomia
unexplained IUD
PET

Front 42

what are the effects of pregnancy on diabetes?

Back 42

- poorer control
- deterioration of renal function
- deterioration of ophthalmic disease
- gestational diabetes mellitus

Front 43

Outline the effects of diabetes on the foetus & the increased risks (6)

Back 43

- maternal diabetes --> hyperglycaemia
- foetal hyperinsulinaemia
- increased foetal growth leads to:
1) foetal macrosomia (risks in birth)
2) polyuria -> polyhydraminos (preterm/cord prolapse)
3) increased O2 demand -> polycythaemia (stillbirth)
4) neonatal hypoglycaemia (cerebral palsy)

Front 44

Outline metabolism changes in mother in pregnancy (4)

Back 44

- reduction in maternal blood glucose & aa concs
- maternal insulin resistance (2nd half of preg)
- increase in FFAs, ketones & triglycerides (alternative metabolic fuel)
- increased insulin release in response to normal meal

Front 45

How is maternal insulin resistance useful?

Back 45

maternal glucose usage declines
gluconeogenesis increases
maximal glucose availability to foetus
mother metabolises peripheral fatty acids

Front 46

In early pregnancy, progesterone stimulates appetite & promotes maternal deposition of fat - how is this beneficial in late pregnancy/after birth?

Back 46

- maternal preparation e.g breast growth
- reserve when foetus is metabolically demanding
- fat (rather than glucose) is primary energy source for mother in later pregnancy