1
Q
What are the features at anatomy scan which should prompt recommendation for a TV USS to look for vasa praevia at 28-32 weeks?
A
bi or multilobed placenta, low lying fetal vessles <5cm, low lying placenta, velamentous cord insertion, no previous scan and risk factors
2
Q
What is classified as a low lying fetal vessel?
A
<5cm from os
3
Q
If women are asymptomatic of vasa praveia should you offer a repeat USS and when?
A
yes at 32 weeks or after
4
Q
If women are asymptomatic of vasa praveia when should you aim for delivery?
A
from 36+0
5
Q
If women are asymptomatic of vasa praevia but have risk factors for PTB when should you deliver them?
A
from 34+0
6
Q
What are the three types of vasa praevia?
A
- Type 1 - velamentous cord insertion 90%
- Type 2 - succenturiate lobe 10%
Type 3 - abnormal fetal vessels branching off the placenta and lying unprotected near cervical os. Arise from resolution of LLP
7
Q
What is the definition of vasa praevia?
A
The presence of unprotected fetal vessels within the amniotic membranes over or close to the internal cervical os
8
Q
What is the survival rate if vasa praevia is undiagnosed in labour?
A
44-70%, eg mortality of 60% improves to 99% when diagnosed. OR 25
9
Q
What are the risk factors for vasa praevia?
A
velamentous cord insertion, bi/multilobed placenta, low lying placenta or resolved placenta praevia, multiple gestation, ART
10
Q
If vasa praevia is diagnosed <26 weeks what are the chances of resolution?
A
60%
11
Q
What kind of vasa praevia is more likely to resolve?
A
type 1
12
Q
When and how should women with low lying fetal vessesl be delivered?
A
C section birth should be considered 37-38 weeks. As they are less likely to experience early ROM and PTL.
13
Q
Should women with low lying fetal vessels have in or outpatient management?
A
there is limited evidence but the risks are primarily in labour, these women are safe for outpatient management.
14
Q
What did the meta-analysis 2024 show about vasa praevia in vs out patient admission?
A
no difference in - NICU admission, fetal death, apgars, fetal trans fusions
Differences in - less Em CS for inpatient but earlier CS for inpatient,s increase in CS inthe symptomatic group.
15
Q
When is delivery indicated for vasa praveia in otherwise uncomplicated pregnancy?
A
36+0-36+6
16
Q
In women with risk factors for PTB when should you consider CS for vasa preavia ?
A
In women with risk factors for PTB consider CS from 34+0
17
Q
In women with otherwise uncomlicated twins a cervical length of 25-30mm and vasa praviea, when should you consider CS?
A
36+0
18
Q
What is fetal survival rate of vasa praevia if not diagnosed antenatally?
A
40-70% (vs 99% diagnosed antenatally)
19
Q
What is the definition for placenta acreta?
A
densely adherent placenta due to abnormally deep invasion of the placental villi onto the uterine muscle surface, possibility placenta will separate at birth
20
Q
What is the definition for placenta Increta?
A
adherent placental villi embedded into the uterine muscle wall, placenta unlikely to separate at birth
21
Q
What is the definition for placenta percreta?
A
Percreta: adherent placental villi growing through/beyond the uterus and with possible involvement of other organs
placenta unlikely to separate at birth
22
Q
What are the risk factors for placenta acreta?
A
Previous CS
multiparity
AMA
placenta praevia
23
Q
What are the rates of PAS in NZ and australia?
A
44 per 100,000 or 1 in 2000
24
Q
what are the USS findings of PAS?
A
placental lacunae
loss of retroplacental clear space
bladder border abnormalities
colour doppler abnormalities
25
USS vs MRI for PAS?
USS should be first line as it is cheap, widely available, and has comparable diagnostic accuracy than MRI
USS is not sensitive but it is specific.
MRI should be used as an adjunct when uncertain diagnosis or other reasons, good predictive value in location of invasion
26
who should be in the MDT for PAS?
consultant obstetrician, consultant anaesthetist, specialist with with skills for diagnosis, specialists with skills in complex surgery such as but not limited to gynae-oncologists, urologists, urogynaecologists, colorectal surgeons, vascular surgeons and interventional radiologists
27
What should be in the management plan for women with PAS?
On site transfusion service/critical bleeding service haematological expertise
Discussion and consent, including possible interventions (hysterectomy, leaving placenta in-situ, cell salvage, IR)
Local availability of adult and neonatal ICU
Provision of patient information for women and their families
Timing of birth should be based on clinical grounds and the need to optimise fetal maturity
28
What study is there for evidence on conservative vs CS hysterecomy of PAS?
observational only
PACCRETA 2022 french - conservative (placenta in situ) vs CS hyst
conservative less likely to need hysterectomy, less blood loss and transfusion, organ injury and maternal morbidity. conservative group more likely to need IR, have endometritis, readmission and 22% had CS in 6 months
IS-PAS (2021)
euro and US, looked at surgical approaches
Unplanned hysterectomy had greater blood loss
No difference in blood loss between partial myometrial resection and planned hysterectomy
MROP was associated with a reduction in blood loss however attempted less frequently, and only in lower grades of PAS
29
When is it suitable to offer uterus conserving procedures in PAS?
appropriately counselled women who are willing to follow advice regarding the need for close surveillance, services must have capacity for emergency hysterectomy and emergency massive transfusion
30
Should you do an MROP in PAS?
no, can cause severe haemorrhage
31
When are bakri and B lynch useful in PAS?
if the placenta separates spontaneously
32
What is the advice for IR in management of PAS?
routine use is not recommended.
Studies have not found a significant difference in blood loss or need for CS hyst
33
What are the risks associated with vasapraevia?
Vessel are unprotected due to not being in wortons Jelly in umbilical cord so they are exposed to vessel rupture, kinking with UA and thrombi. Associated with IUGR, fetal distress and asphyxia, PTB, IUFD
34
What is the cause of vasa praevia?
maybe placenta trophophism - migration of placenta to places to high blood supply. Placenta moves at about 1mm/week but the cord cannot keep up.
35
What is the recommended care in pregnancy for velamentous cord insertion?
TV USS to exclude vasa praevia, consider growth surveillance, weekly CTG from 36 weeks to detect vessel kinking or compression, delivery by 40 weeks to reduce risks of vessel compression with oligo hydramnio
36
What are the risks of velamentous cord insertion?
vessel rupture, kinking or compression, asphyxia, death, thrombosis with limb ischaemia, FGR and retained placenta, PIH and PTB, IUFD
37
What is the recommended care in labour for velamenous cord? what is the risk of needing MROP?
CTG in labour, 5% risk of needing MROP
38
How common is velamentous cord insertion in singleton and twin pregnancy?
1% v 15%
39
What are the related conditions to velamentous cord?
2VC 12% and vasa praevia in 2%
40
What is the definition of placenta praevia?
the placenta lies directly over the internal os in pregnancies, greater than 16 weeks
41
What is the definition of low lying placenta?
the placental edge is <20mm from the internal os, greater than 16 weeks
42
What are the risk factors for placenta praevia?
ART, rising CS, AMA and smoking
43
How should we check and diagnose placenta praevia or LLP and what route of scanning is needed?
1. at FAS all placentas should be assessed for being LL or PP and this can be assessed on TAS or TVS
2. Of those that are thought to be LLP or PP at FAS should have a TVS at 32 weeks to diagnose.
3. If remains low or praevia at 32 weeks should have repeat 36 week TVS to inform delivery palnning
44
What proportion of low lying placentas will resolve by term?
90%
45
What is the false negative rate of TVS in detecting PP?
2.3%
46
When is cervical length monitoring useful in PP?
asymptomatic women with a short cervix (<25-31mm in literature) prior to 34 weeks have an increased risk of massive PPH and preterm emergency CS.
47
What groups have increased risk of early emergency CS needed in PP?
multiple APHs, APH <29 weeks
48
How should asymptomatic women with PP be looked after in T3?
as outpatients, advice given on risk of PTB and massive haemorrhage. Should have safety precautions in place at home including having someone available to help them and access to hospital
49
When should you consider steroids in PP or LLP?
A single course of antenatal steroids is recommended in women with LLP or PP from 34+0 to 35+6, consider prior to 34+0 in women at risk of PTB
50
What outcomes do steroids in PP reduce?
Reduced respiratory complications, IVH, NEC, RDS, death
51
What are the risks for the neonate with PP?
increased risk of low apgars at 5 minutes, NICU admission, anaemia, RDS, mechanical ventilation and IVH
52
When should you consider delivery for women with PP who have had bleeding in pregnancy?
34+0 - 36+6
53
When should you consider delivery for women with PP who have risk factors for preterm birth?
34+0-36+6
54
When should you consider delivery for women with PP who have uncomplicated PP in pregnancy?
36+0-37+0
55
What factors should be considered when deciding on mode of birth for women with a LLP?
womens wishes, clinical histroy, USS findings. If edge of placenta thick >10mm, or marginal sinus, more likely to bleed in labour needing CS. if the distance 10-20mm away chances of success range from 56-93%
56
What should be discussed with a woman with PP when planning for delivery?
if they will accept blood products and document this.
57
What is the RR for massive haemorrhage with PP?
12
58
What are the other risk factors that can increase bleeding risk in CS at PP?
Mg use, thrombocytopenia, anemia and diabetes
59
What should be considered in the surgical approach for PP?
bedside USS to confirm incision
consider vertical incision if transverse fetus
if placenta is transected, immediately cuit and clamp to reduce fetal blood loss.
early consideration of options, including iR and hyst
60
what is a red cell antigen?
glycoproteins and glycolipids woven into the red cell lipid bilayer (making up the cell membrane)
61
How many different rhesus system antigens are there?
45
62
Which rhesus system antigens can cause HDFN?
all of them theoretically
63
Which are the most common rhesus antigens which cause HDFN?
D c and E (anti D causes the most deaths)
64
How many antigens in the Kell system
26
65
Where is the K antigen found in fetuses and how is this relevant to presentation?
in the bone marrow
Anti-K causes bone marrow suppression and anaemia
66
what is the most common kell antigen to cause an antibody response?
K antigen with anti K antibodies
67
what are A and B antigens made from?
oligosaccharides on red ell surface
68
Where are A and B antigens coded on?
chromosome 9
69
What kind of IG are anti B and Anti A usually?
IgM
70
How do people usually develop anti A and B antibodies?
usually from exposure to other structures eg bacteria with similar antigens to ABO
71
What problem can O blood group cause for antibodies and fetuses?
can have anti A and B antibodies which can cause mild HDFN (needing phototherapy or exchange transfusion)
72
What are the main antibodies which cause severe anaemia, jaundice or death of the neonate?
anti K, D and c
73
What are the other red cell antibody groups which can cause HDFN?
MNS system
Duffy system
Kidd system - rarely (more common to cause delayed transfusion reaction)
Diego and colton (rare)
74
Which antibodies are in the MNS system?
anti-M, anti-S, anti-U
75
which antibodies are the in the Duffy system?
Anti-fya, anti-fyb
76
Which antibody is in the Kidd system?
Anti JK
77
Which antibody only causes HL transfusion reaction if active at 37 degrees?
anti M
78
How many different polymorphisms are there on platelet membrane glycoproteins? what are they?
6. HPA-1 to 5 and 15 but htere is alo a 6
eg HPA-1a is a kind of antigen
79
what are the most common antigens to cause alloimmune thrombocytopenia in Maori, european and Pacific?
Europeans - HPA-1a 73% HPA-5b 20%
Maori HPA 2b and 3a
Pacific HPA 6b
80
What is NAIT?
Neonatal alloimmune thrombocytopenia (can effect fetus)
81
What is the difference between alloimmunisation primary and secondary response?
primary - low levels of antibodies
secondary clinically significant levels of antibodies
82
What is the likelihood of developing anti D after delivery vs transplacental haemorrhage >1ml?
1-1.8% vs 30%
83
Why do you get platelet alloimmunisation during first pregnancy but not red cell?
platelet antigens are more immunogenic and antigens may cross the placenta as early as 14 weeks from trophoblast invasion
84
Where does haematopoiesis occur in the embryo and fetus and when?
yolk sac from day 21, then liver from week 8, then bone marrow from T3
85
how does red cell antibody cause anaemia?
igG crosses placenta, attaches to the red cells and these are then destroyed extravasculalry by RES in the spleen and liver
86
Which antigens are expressed on fetal red cells?
rhesus from day 30 gestation (anti D can effect)
ABO only weakly expressed
87
Explain the findings and the pathophysiology of fetal anaemia?
1. increased erythrpoiesis - heaptosplenomegaly
2. increased CO - dilated ventricles, tricuspitd regurg and cardiac dysfunction
hypoxia leads to tissue damage:
3. myocardium - pericardial and pleural effusion
4. endothelium - increased capillary permeability, protein loss, third spacing (ascites, effusion, skin oedema)
88
How early can NAIT present
as early as 16 weeks in first pregnancy
89
How does NAIT present?
usually at birth.
50% will have platelet count less than 20
20-30% will have CNS haemorrrhage with 50% occurring in utero (death and sequelae)
petechial rash, rectal bleeding, bleeding from wound sites
90
how does anti D prophylaxis work?
IgG whoch bind to antigen on RBC and then it is cleared prior to mum being able to make an immune reponse
91
From what gestation do you do a kleihauer?
20 weeks
give normal dose + kleihauer
because prior to this the standard dose would cover any FMH
92
How does antibody titre interpretation work?
it is the number of times you need to dilute the sample in order to be able to get an undetectable sample. so the higher the number the more antibody/more severe. eg 1:2 is less anti body than 1:32
93
How can you detect if the fetus is at risk of alloimmune disease?
NIPT or paternal genotype
94
How do you manage fetal anaemia secondary to alloimmunisation?
intrauterine transfusion or deliver and extra uterine transfusion
PETIT study found IVIg to mum just delayed transufsion by 6 days and increased ADRs and $$.
95
What is usually a significant titre level for antibodies? what is the eception
1:32
except K where all are significant
96
How do the antibodies get through to the baby's circulation?
Fc receptors on the syncytiotrophoblast takes it through to the fetal circulation. by endosome formation, stops it getting degraded and is recycled back to mum
97
What is the new medication being used to reduce HDFN?
nipocalimab - mab, binds to Fc receptor stops alloantibodies from binding. take nipocalimab across and the alloantibodies are degraded
98
If women have anti D, c or K antibodies found, how often should you check them?
monthly to 28 weeks, then 2 weekly from 28 weeks
99
How can you detect the gentotype of the fetus for alloimmunisation concerns?
paternal genitype
NIPS
CVS or amnio (if other antigens needed but can be a sensitising event)
MCA Vmax - fetal anemia
100
when should fetuses at risk of HDFN be born?
37 weeks
101
How is anti D level reported and why?
IU/ml as titre doesn't correspond with HDFN
102
What are the levels of HDFN unlikley, moderate risk or high risk with anti D?
<4 IU/ml unlikely
4-25 moderate risk
>15 high risk hydrops
103
What proportion of women are rehsus negative?
1/7
104
What is the dose of anti D in first trimester and what are the indications?
250 IU (625IU in twins)
TOP> 10 weeks
miscarriage
ectopic
CVS
molar
recurrent heavy PVB and pain
105
What is the dose of anti D in second and third trimester and what are the indications?
625IU
APH
Trauma to the abdomen
CVS/amnio/procedure
ECV
Miscarriage/IUFD
TOP
106
When should anti D prophylaxis be given?
625 IU at 28 and 34 weeks or 1250 at 30 weeks (NZ blood)
107
When and how should it be given post natally?
in 72 hours
625IU plus kleihauer
108
to what extent does antenatal redce anti D reduce alloimmunisation?
from 1% to 0.35%
109
What is the chance of making anti D after each positive pregnancy?
8%
110
What is the time frame for anti D to work?
72 hours ideally but some effect to 10 days
111
When should you consider IV anti D ?
if more than 2 vials of anti D needed eg 2 x 625
112
One anti D 625IU vial should cover what level of haemorrhage?
6ml
113
If continuous bleeding how often should you give anti D?
2 weeks
114
How can you tell the difference between passive anti D and active?
check titres 2 weekly and if increasing active
115
What is PROM?
Prelabour ROM
116
What is the incidence of PROM?
8%
117
What proportion of women will labour after 24 hours, 48 hours and 96 hours spontaneous after PROM?
70%
85%
95%
118
What are PROM risks immediately and delayed?
immediate - cord prolapse, cord compression, abruption
delayed - infection maternal and neonatal
119
What can cause false positives with amnisure?
trichomonas
semen
blood
cleaning solutions
lubricants
BV
120
When should you avoid VE in PROM?
all cases unless immediate IOL planned
121
When should you offer IOL for GBS PROM?
immediately
122
PROM within 24 hours vs expectant management findings?
reduced chorio, sepsis, CS, neonatal abx, NICU admission
123
If a patient declines IOL for prolonged ROM, what criteria should she fit ideally?
* Confirmed cephalic
* Negative GBS
* No signs of Infection
* Normal CTG
* Clear liquor
* Adequate resource to provide support
* Commitment to regular obs and FM checks, including 4 hourly temps while awake
* Access to transport
* Document review
124
Should women who are known to be GBS negative have abx if timely IOL is provided?
no
125
When should you give 3g cefazolin?
when patient over 120kg
126
When should you redose cefazolin at CS?
after 3 hours if prolonged case
127
If severe penicillin, allergy what antibiotics should be given?
clinidamycin 600mg IIV and gentamicin 2mg/kg IV
128
If MRSA positive at CS what shouldyou give?
vancomycin 15mg/kg
129
What benefit does antibiotics for PPROM have?
reduced maternal and neonatal infections and prolonged pregnancy (reducing GBS). Less likely to deliver at 48 hors and 7 days
No evidence to show improved perinatal mortality and long term outcomes
130
What is the recommended antibiotic regime for PPROM?
Erythromycin 250mg QID for 10 days
+/-
Amoxicillin 2g IV Q6 hourly for 48 hours then amoxicillin 250mg PO q8hrly for 5 days
Azithromycin has been shown to be equally effective to erythromycin and may have better side effect profiles
131
What does indirect coombs test?
free floating antibodies
132
What does direct coombs test?
antibodies or complement on the surface of RBC
133
In NZ and Australia what percentage of births are pre term
7-7.5%
134
In australia and NZ what proportion of neonatal deaths are accounted for by PTB?
65-70%
135
What RR did the OPPTIMUM trial show in progesterone for cervixes <25mm?
RR 0.62 PTB <33 weeks
136
for which patients is cervical cerclage proven to be most effective?
reducing PTB in patients who have a singleton pregnancy and:
short cervix (0.74), particularly with hx previous PTB (0.61) or mid trimester loss (0.57) and those with progressive shortening despite progesterone
137
What is the cut off measurement for cervical length TA for further investigation?
pre void, TA 36 mm
138
What is the PPV and NPV for PTB if you are found to have a mid trimester cervical length of <25-30mmm after CIN treatment?
30-50%
NPV 94-95%
139
What is the advice about cervical length monitoring in twins?
has a predictive value in predicting PTB but evidence for therapeutic intervention is conflicting. Most helpful in optimising for outcomes
140
What is the importance of amniotic debris?
if found with a short cervix it is predictive of PTB, associated with inflammatory marker s nd clinical chorio
141
What is RANZCOG's statement universal cervical length screening?
supports initial TA scanning with singleton pregnancies at midtrimester scan and addition TV is <35mm or unable to be clearly viewed.
142
what proportion of PTB occurs spontaneously?
2/3
143
What proportion of people who have PTB no have risk factors?
2/3
144
At what cervical length would cerclage be the preferred treatment in mid trimester scan?
<10mm
145
How should a cervical length be measured properly?
TV, probe in anterior fornix, empty bladder, minimising pressure on cervix. measure from internal to external os and repeat 3 times over 5 minutes and take shortest
146
how much for the TA overestimate cervical length compared to TV when full bladder?
6mm
When empty can be more accurate but more are unable to see cervix
147
Can you use TV scanning in PPROM ?
yes
148
WHat are common cut off for treatment with progesterone and cerclage?
<25mm progesterone 200mg PV nocte
<10mm cerclage
149
Out of ablation, LLETZ, cone what are associated with PTB?
all
150
Has universal cervical length scanning proven to be cost effective?
not really, a small increase in costs, but is still recommended by these studies
151
Who should PV progesteron be considered for?
women with cervical length <25mm who are asymptomatic
* consider* in women who have a singleton pregnancy and a history of spontaneous PTB
152
What is the data on previous PTB and progesterone use?
meta analysis of 5 studies showed reduction in PTB, perinatal mortality and major morbidity
then the 2016 OPPTIMUM study showed no reduction in PTB
153
What is the evidence of reduction in PTB for women with an asymptomatic short cervix 18-24 weeks?
meta analysis significant reduction PTB <34 weeks 27% --> 18%. 34% reduction
also reduced RDS, neonatal morbidity and mortality, BW and NICU admission
perinatal mortality not SS
154
When should vaginal progesterone be started?
16 weeks
155
What is universal based GBS screening?
culture based screening using a combines low vaginal +/- anorectal swab at 35-37 weeks. or 3-5 weeks prior to anticipated delivery of high risk pregnancy.
156
what needs to be done with the swab and form when screening for GBS?
vaginal +/- anorectal swab.
Can be one or two. If one, vagina then rectum.
Document it is for GBS screening (specific media), and document allergies, store in fridge if not sending immediately
157
If a woman's GBS status is unknown, how should she be treated?
based on risk factors
158
What antibiotics are appropriate for the management of GBS prophylaxis in labour?
penicillin G or ampicillin
159
What are acceptable alternatives for GBS prophylaxis in labour for GBS?
cefazolin, clindamycin, vancomycin. depending on resistance
160
What proportion of mothers are colonised by GBS?
10-30%
161
What proportion of babies born to mothers with GBS will become colonised?
40-50%
ASID says up to 70%
162
Without antibiotics in labour what proportion of babies will get EOGBS?
0.4-4 per 1000
163
If babies get EOGBS what proportion will die?
14% total but 20% in preterm (ten fold higher than term)
164
What are the common signs of EOGBS?
respiratory symptoms and pneumonia
165
What is the time frame for late onset GBS?
7 days to 3 months
166
What is the reduction in EOGBS with antibiotics in labour?
80%
167
What is the risk of anaphylaxis with penicillin?
4 in 10,000 to 4 in 100 000
168
What is the symptoms of later onset GBS?
meningitis or septicemia
169
Do intrapartum antibiotics help reduce late onset GBS?
no
170
What are the risk factors for EOGBS?
spontaneous labour <37 weeks
ROM >18 hours
maternal fever >38.0
GBS in urine in current pregnancy - Increased risk EOGBS
Previous infant with early or late onset GBS
known carriage of GBS in this pregnancy
clinical diagnosis of chorio
other twin with EOGBS
25% of EOGBS cases have no risk factors
171
How much more likley are PT babies to get EOGBS regardless of screening approach?
4 x than term
172
When is the GBS culture swab most relevant?
within 5 weeks of delivery
high sensitivity and specificity and NPV 95-98%
173
When is the aim of getting antibiotics administered in GBS?
4 hours prior to delivery
174
How should you manage threatened PTL with unknown GBS status?
take a swab and if establishes, start antibiotics
175
With a woman with GBS postivie and >34 weeks how should she be managed?
offer IOL or immediate delivery
176
If women decline antibiotics what should be done?
advise them the risk of the baby developing IAP is significantly higher and their baby should be monitored for 12 hours after birth
177
How do you manage previous GBS carriage in another prgenancy?
about 50% will have recurrence in future pregancies, offer IV in labour or testing in late pregnancy
178
What is the benefit of adding anorectal swab for GBS?
increases detection by 25%
179
What antibiotic regime does ASID recommend for GBS prophylaxis?
ben pen 3g then 1.8g 4 hrly or
cefazolin 2g then 1g 8 hourly
or anaphylaxis
vancomycin 1g 12 hourly or clindamycin 900mg 8 hrly
180
When does EOGBS present? and what is the most common time?
in the first 7 days but
in the first 12 hours in 90%
181
why is sensitivity to antibiotics important for GBS management?
clindamycin and erythromycin resistance is increasing.
182
what are the categories of pre term birth?
Late preterm birth (34+0 to 36+6) = 70% of preterm births
Moderate preterm birth (32+0 to 33+6)
Very preterm (28+0 to 31+6)
Extremely preterm (less than 27+6 weeks)
183
How often is no cause found for PTB?
50%
184
what proportion of preterm birth is iatrogenic?
25%
185
What are the maternal risk factors for preterm birth?
age <18 or >35
ethnicity - immune responses and vaginal microbiome
cervical surgery or pathology - especially>20mm LLETZ
congential uterine anomalies
BMI <18 or >30
medical comorbidities - HTN, SLE, diabetes, autoimmune, renal
nutritiion - IDB, malnutrition, gastric surgery, low SES,
smoking
previous PTB or T2 loss or PPROM
multiple pregnancy
Increased maternal height
ovulation induction
186
What is your risk increase if you have a PTB of having another?
1 previous 4 x
2 previous 6.5 x
187
How does progesterone work?
uterine quiescence and anti inflammatory
188
Why is it difficult to interpret some of the studies on progesterone and PTB?
they studied IM vs PV
189
What are the indication for cervical cerclage?
hx of PTB
hx of cerclage for painless dilatation in the 2nd trimester
cervix is <25mm at <24 weeks with a history of PTB
190
Cerclage is not reccomended when?
cervix <25mm at <24 weeks without history of PTB
funelling without shortening
history of cervical surgery or anomaly
multiple pregnancy
191
What is the outcome of the Cochrane review for optimum mode of delivery for PTB?
122 women, RCTs, no difference in birth injury, HIE, deaths, RDS. 7 major maternal post partum complications in CS non in vaginal.
Unable to conlude which is better
192
What does the ranzcog module recomned for mode of delivery for PTB?
<26 weeks - vaginal
26-37 - case dependent
193
What are the maternal contraindications to nifedipine for tocolysis?
SBP <90
cervix >3cm espiecially with PPROM
hyper sensitivity
cardiac abnormailites
hepatic dysfunction
use of IV salbutamol
194
What is the roles of antibiotics in TPTL?
none, associated with cerebral palsy
195
If you expect baby to delivery in the next * days, give steroids?
7
196
who do you give steroids with caution to?
sepsis, diabetes, chorio
197
Who would you consider giving a rescue dose of steroids to?
after 7 days if <32+6 and still at risk of delivery
198
What are the CI for MgSO4?
maternal heart block
myasthenia gravis, caution with nifedipine
199
What ist the regime and time frame for MgSO4?
Start 4 hours prior to birth
4g IV bolus over 20mins then 1g/hr until delivery
200
What are the improvements seen in PTB for MGSO4?
Reduction in NND 15% NNT 42
reduce CP by 30% NNT 63
201
How can you reduce the risk of PTB in future with pre pregnancy counselling?
Previous gestation of PTB correlates to risk of timing in future
* Lifestyle: optimise BMI, smoking, medical comorbidities
* IPI <6 months increases risk for preterm labour
* Screen for untreated CIN
* Consider the use of cervical length measurements from 16-24 weeks +/- progesterone or cerclage if shortening
* Testing for asymptomatic bacterial vaginosis and STIs
Routine urine MC,S to rule out asymptomatic bacteriuria.
202
What proportion of twins are born Preterm?
50%
203
What are the survival outcomes at 23 weeks vs 26 weeks ?
40% and 80%
204
at extreme preterm gestations, what is the benefit in survival each day?
3%
205
What are the four broad pathogenic pathways of PTB?
1. hormonal - activation of the maternal/fetal hypothalamic pituitary adrenal axis. From maternal or fetus stress. cortico tropin releasing hormone and estrogen --> prostaglandins
2. infection/inflammation
3. decidual haemorrhage - thrombin increases protease and PG production
4. pathologic uterine distension - enhanced gap junction between myometrial cells, increased oxytocin receptors and PG production
206
PTB and risk of recurrence after 1, 2 and 3?
1 16-19%
2 32-40%
2 67%
207
What does fetal fibronectin measure?
a glycoprotein from the choriodecidual interface due to inflammation or mechanical trauma
208
What are the contraindications to testing FFN?
Gestation <24 weeks or >34 weeks (uterine sound said 22 or 35 due to lack of formation of interface and natural breakdown of the interface)
bleeding
lube use
vaginal exam or intercourse within 24 hours
cervix >3cm
PPROM
multiple pregnancy
209
What does partosure measure?
placental alpha microglobulin -1 (PAMG-1)
phosphorylated insulin like growth factor binding protein 1 (phlGFBP-1)
210
how do you interpret a negative partosure result?
95% chance of not giving birth in the next 7 days
211
When using the QUiPP app what is the recommended cut off for intervention?
5% risk of delivery in 7 days
212
Why do we treat symptomatic bacturia?
As 30% will develop pyelonephritis without it. and reduces risk of low birth weigth babies
does not reduce the risk of PTB
213
What is the association with peridontits and PTB?
increases risk but unclear if causal or just marker of other health behaviours
214
What is the definition of cervical insufficiency?
painless dilation or cervical shortening of the cervix in the second trimester
215
What are contraindications to stitch placement?
fetal anomaly
infection
active bleeding
PPROM
216
What would be the indication for a prophylactic cerclage?
2 preterm births or T2 losses
217
What is the data on rescue cerclage?
limited
218
If women have a shortened cervix <25mm with no history of PTB what is recommended?
progesterone first
219
What data is there for comparing cerclage with progesterone?
both equally as efficacous from data which is difficult to compare
220
What are the possibilities of why studies find no improvement with tocolysis?
under powered
hetorogenous group
heterogeouns condition
unfavourable intrauterine environment
221
What is the definition of cerebral palsy?
a group of permanent disorders of the development of movement and posture causing activity limitation that are attributed to non progressive disturbances that occurred in the developing fetal or infant brain
222
What did the cochrane review of ‘Magnesium sulphate for women at risk of preterm birth for the neuroprotection of
the fetus’ 2024 find?
6 RCTs 6759 fetuses
PTB <34 weeks
CP RR 0.71 NNT 60
death or CP 0.87 NNT 56
Reduced IVH RR 0.76
No difference in CS PPH
223
How does MgSO4 reduce risk of CP?
MgSO4 is important for key cellular processes.
The newborn brain is more susceptible to damage from glutamate release. MgSO4 Blocks glutamate receptors and also excessive release from calcium channel
224
PPROM complicates what number of pregnancies and is associated with what number of PTB?
3% of all pregnancies and 30-40% of PTB
225
What the neuro developmental complications are related to extreme prematurity?
Cerebral palsy
Gross motor developmental delay
Behavioural disorder - ASD
Retinopathy of prematurity
Intellectual impairment
Neurodevelopmental delay
Hearing impairment
226
What are the physical complications related to PTB?
* IVH
* RDS
* Bronchopulmonary dysplasia
* NEC
* Anaemia
* Jaundice
* Hypoglycemia
* Pneumonia
* Sepsis
Patent ductus arteriosis
227
cervical surveillance should be done from when to when in high risk groups?
16-24 weeks
228
What is the data on progesteorne for women who are high risk of PTB?
OPYIMUMM 2016 found no reduction in PTB with PV progesterone
EPPPIC meta-analysis of 31 studies, 11 644 women found <34 PTB with PV progesterone RR 0.78
229
What is the pathophysiology of RDS?
Surfactant deficiency
Increased surface tension in alveoli
Atelectasis and impaired gas exchange leading to hypoxaemia
Inflammation and oedema
230
When does GTG recomend delivery for placenta accreta with abscense of other risk factors?
35+0-36+6
231
What are modifiable risk factors of PTB?
BMI
smoking
optimise medical comorbidities
IVF single embryo transfers
IPI 18 months
correct anatomical abnormalities possible
sceen for CIN
232
Ellen's flashcards
flashcards
Decks in class (27)
# Cards
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Week 419
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Week 585
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Autoimmune medications and pregnancy11
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Landmark trials to date13
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Week 6253
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Week 7259
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Week 8232
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Week 9206
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Week 10364
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Week 258
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week 371
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Week one136
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Week 11237
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Week 12314
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Week 13381
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GONC 1395
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GONC 2259
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Week 16134
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Week 17410
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Week 18266
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Week 19347
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Week 20307
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Week 21430
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Week 22370
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Week 23298
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Week 24325
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Week 261
