Pregnancy and lactation Flashcards
(81 cards)
1
Q
What does antenatal mean
A
The time frame of which the female is pregnant
2
Q
What 7 conditions could occur during pregnancy
A
- Emesis (or Hyper emesis)
- Pregnancy induced hypertension
- Pre-eclampsia
- Eclampsia
- VTE
- Gestational Diabetes
- Infection
3
Q
What does teratogenicity mean
A
The ability of a drug/agent to cause foetal abnormalities or deformation
4
Q
How do teratogens cause abnormalities
A
- By crossing the placenta
- Vasoconstriction of placental vasculature - reducing blood flow to foetus
5
Q
The foetal response to a teratogen depends on what 5 factors
A
- Dose
- Route
- Timing of exposure
- Genetic and environmental factors
- Number of concomitant drugs
6
Q
What affects the foetal response to carbamazepine
A
Dose related response
7
Q
What are the 3 human development phases
A
- Pre-embryonic
- embryonic
- Foetal
8
Q
What is the pre-embryonic phase
A
Conception to day 17
9
Q
What is the teratogenic risk for pre-embyronic phase
A
Drug exposure can cause spontaneous miscarriage or prevent embryo attaching to uterus
All or nothing period, if most cells affected then spontaneous miscarriage occurs.
10
Q
What is the embryonic phase
A
Day 18- 55
Greatest period of vulnerability as tissue is rapidly differentiating and major organs being formed.
11
Q
What is the teratogenic risk for embyronic phase
A
If the differentiating cells are damaged then structural abnormalities can occur i.e cleft lip
12
Q
What is the foetal phase
A
8 weeks to term
Continual development of organs such as cerebral cortex and glomeruli
13
Q
What is the teratogenic risk for the foetal phase
A
Functional abnormalities such as deafness occur as opposed to structural abnormalities
14
Q
What type of drugs cross the placenta
A
Non-ionised,
Lipid soluble drugs
LMW
15
Q
which one will cross the placenta: Atenolol or labetolol?
A
Labetelol
Lipid soluble
16
Q
What 3 High molecular weight drugs will not cross the placenta
A
Insulin
LWH
Infliximab
17
Q
What are the 8 potential harms to foetus (WINS PISM)
A
Withdrawal
Intrauterine growth restriction
Neonatal side effects
Stil birth
Prematurity
Impaired neurodevelopment
Spontaneous abortion
Malformations
18
Q
What drug causes still births
A
Warfarin
19
Q
What drugs cause prematurity
A
Statins
20
Q
What drugs cause neonatal side effects
A
CNS depressants i.e opioid
21
Q
What drugs cause withdrawal reactions in neonate
A
Opioids
Benzodiazepines
22
Q
What drugs impair neurodevelopment
A
Sodium valproate(Neural tube defects)
23
Q
What drugs cause spontaneous abortion
A
Isotretinoin
24
Q
What drugs cause interuterine growth restriction
A
Beta-Blockers
25
4 mechanism of harm
Passive diffusion
Placenta
Uterus
Mother
26
Passive diffusion harm mechanism
Molecules pass through placenta into foetal blood stream
Most common mechanism
27
Placenta harm mechanism
Damage to placenta i.e vasoconstriction results in reduce oxygen and nutrient to baby.
OR the placenta not functioning appropriately
28
Folate supplementation in pregnancy
Advised to take in the first trimester to prevent neural tube defects
29
What is the dose of folic acid
400mcg OD
or
5mg OD if
- High risk of folate deficiency
- Previous child with folate deficiency,
- Certain antiepileptics
- Diabetes, coeliac disease, sickle-cell disease, or thalassaemia.
30
Uterus - Harm mechanism
Physical damage to uterus i.e accidents
or
Medicines causing uterus to contract inducing early labour
31
Mother - Harm mechanism
if mother is sick then baby may be impacted.
32
Name the 2(SALT) teratogens
Sodium val
Statins
AceI
ARBS
Lithium
Live vaccines
Tetracyclines
Thalidomide
33
Name the CVD WIN MF teratogens
Chloramphenicol
Valproate
DOACs
Warfarin
Isotretinoin
NSAIDs
Methotrexate
Fluconazole
34
When are NSAIDS avoided in pregnancy
3rd trimester
35
What is the exception for NSAID use in pregnancy
Aspirin for pre-eclampsia
Risk Vs Benefit
36
What is the risk of neurodevelopment disorders with sodium valproate
30-40%
37
What is the risk of congenital malformations with Valproate
10%
38
What conditions must be met for women to be on valproate
The pregnancy prevention programme
39
How frequent is pregnancy testing on valproate
Monthly basis before issuing/prescribing their next supply
40
When should explain valproate risks to patients
before prescribing and at every annual review
41
What is the annual risk acknowledgement form for valproate
to acknowledge they understand the risk of taking valproate
42
What is the Valproate use in Men risk
Possible risk of infertility
Possible risk in babies whose father has taken valproate
43
What should a men on valproate's partner do
Be on contraception
44
What are the pharmacokinetic changes in gastro-intestinal absorption during pregnancy
1. Prolonged gastric/intestinal emptying
2. Reduced gastric acid secretion and increased pH and mucus secretion
Impacts ionisation and absorption of weak acids and bases.
N/V reduces [drug]
45
What are the pharmacokinetic changes in lung absorption during pregnancy
1. Increased carbon monoxide
2. Increased tidal volume increase uptake of inhaled medications may need to reduce doses of general anaesthetics and gases not asthma meds
46
What are the pharmacokinetic changes in distribution during pregnancy
1. Increase plasma volume
2. Increase in fat stores
3. Less protein binding due to dilutational hypoalbuminemia and placental hormones occupying proteins (phenytoin) thus more free drug
47
What are the pharmacokinetic changes in hepatic metabolism and elimination during pregnancy
1. Increased hepatic BF - faster elimination
2. Increased progesterone which increases metabolism of some drugs and reduces elimination of others
3. Increased oestrogen which interferes with clearance of drugs into billiary system
48
What are the pharmacokinetic changes in renal elimination during pregnancy
1. Increased renal plasma flow and GFR, thus increased elimination of unchanged drugs so longer to reach steady state.
2. Increased renal activity of PGP - decreased concentration of drugs transported by renal system
49
How can fathers affect the baby
1. Exposure to medical or envifonmental factors
- Smoking
- Heavy metals
- Radiation
- Pesticides
- Chemotherapy or teratogenic drugd
50
What medication is immediately reduced after birth
Lamotrigine
51
How long should fathers wait before fathering child after cytotoxic agents
Generally 2 spermatogenic cycles(6 months)
- Cyclophosphamide - 3 months
- Rituximab - 12 months
52
how should you information gather for pregnant women
Planning pregnancy/ already pregnant?
Age of mother
Stage of pregnancy (weeks gestation)
Allergies, PMHx, DHx, SHx etc
Pre-existing conditions (mother + baby)
Any monitoring (e.g. US scans) already being carried out?
Obstetric history - previous pregnancies
Breastfeeding concurrently?
Indication and need for medication being considered.
53
What info should you provided during counselling
Potential consequences of using a medicine during pregnancy
How likely the woman and her child are to be affected
What can be done to manage any risks
54
Polypharmacy in pregnancy
Should be avoided - increases teratogenicity risk
55
What anti-epileptics are the safer options in pregnancy
Lamotrigine and levetiracetam
56
What things you consider when prescribing in pregnancy
- Risk Vs benefit
- Neccessity
- Lowest effective dose for shortest time possibly
- Avoid new medicines
- Avoid polypharmacy
57
6 benefits of Breast feedings
1. Economical
2. Convenient
3. Improves baby-mother bond.
4. Lowers risk of breast, uterine and ovarian cancer, osteoporosis, CVD and obesity risk in mother
5. Composition of breast milks changes in response to babies need( antibodies adnd Melatonin in night feeds)
6. Reduces risk of SIDS, obesity and CVD in adulthoood
58
7 Issues with breast feeding
1. Under pressure to breastfeed(refer to correct support i.e mental health or physical burden)
2. Hard to return to work
3. Pain
4. Need to eat more.
5. Premature babies are deficient in nutrients and requires calorie dense formulas.
6. Mother of premature babies may cease lactating before breast feeding becomes established.
7. mother has Disease/ medication
59
What is the composition of breast milk
A suspension of fat droplets in an aqueous phase containing proteins, lactose and electrolyte
60
How does the composition of breast milk change (3)
Duration of feed
Time of day
Needs of baby
61
What is the WHO recommendations for breast feeding
breast feed for the first 6 months of life, with supplemental breast feeding for two years
62
Why do drug pass more easily into breast milk in the first few days after birth
There are wider intracellular gaps in the milk ducts to facilitate passage of immunoglobulins to the newborn.
Gaps close after a few days and drugs must cross intracellular membranes instead.
63
Why is there not much evidence for use of drugs during breastfeeding
No robust evidence as it is unethical to test on babies
64
If the BNF says a drug is not reccomended in breast feeding what does that mean
Does not mean it isn't safe - just means there is not enough robust evidence that says it is safe
65
what two interesting effects can drugs have on the baby
Some meds may inhibit milk production or inhibit infant’s sucking reflex.
66
if a drug have no oral bioavailability will the baby be affected
No
examples of these drugs: insulin, infliximab, LWMH
67
Can large MW drugs get into milk
Highly unlikely - as it high MW indicates low oral bioavailability.
(Alcohol has low MW)
68
Can drugs be absorbed by the infant gut
Some drugs may enter milk but are not significantly absorbed by infant gut
(Gentamicin, dopamine, insulin)
69
If medication undergoes first pass metabolism is it absorbed by baby
limited amount absorbed i.e morphine
70
Neonatal clearance
Kidney and liver not fully developed at birth so drugs may accumulate. Must consider drug Half-life
(Fluoxetine has long T1/2)
71
Will highly protein-bound drugs enter Breast milk
less transfer into milk
ibuprofen 99% bound
warfarin
72
Milk: Plasma ratio
The lower the milk to plasma ratio the less drug enters the milk. Most drugs have ratio of<1.
Iodine has ratio of 26 - thus avoid iodine dressings
Sertraline has ratio of 0.8
73
Fat solubility of drugs in breast feeding?
Lipophilic drugs may preferentially dissolve in fat globules in milk and therefore can pass through alveoli epithelium
Benzodiazepines amitriptyline
74
What is relevant infant dose
estimate of infants exposure to drug
RID% = (infant dose mg/kg/ mothers dose) x 100
<10% is compatible with breast feeding
10-20% use with caution
20%> Avoid
75
Information gathering in breast feeding
Details about mother AND baby
Usual information gathering including PMHx, DHx
Age of baby – including corrected age (born prematurely or at full term?)
Circumstances of birth/ delivery
Frequency, type, quantity of feeding
type: EBF, expressed bottle-feeding, formula feeding, mixed feeding
Frequency of feeding depends on age
76
Are drugs licensed for use in BF
Most drugs are not - so check resources
77
Can codeine be used in pregnancy
No avoid - dihydrocodeine preffered
78
How can antibiotics affect breast feeding
Some antibiotics cause temporary lactose intolerance in the baby
79
Can antibiotics be taken in pregnancy
If the antibiotic is licensed in children then can be given to breast feeding mother (Level reaching the baby is much lower than the licensed dose)
80
Can sertraline and citalopram be used in pregnancy
Yes, they have been well studied and it has found that very little passes into breast milk.
Stopping breastfeeding may exacerbate depression due to loss of oxytocin
81
