Pregnancy Complications Flashcards
Placenta accreta describes
the attachment of the placenta to the myometrium, due to a defective decidua basalis. As the placenta does not properly separate during labour there is a risk of post-partum haemorrhage.
What can cause placenta accreta
previous caesarean section
placenta praevia
Placenta accreta - there are 3 different types:
accreta: chorionic villi attach to the myometrium, rather than being restricted within the decidua basalis
increta: chorionic villi invade into the myometrium
percreta: chorionic villi invade through the perimetrium
Placenta praevia describes
a placenta lying wholly or partly in the lower uterine segment
Placenta praevia Epidemiology
5% will have low-lying placenta when scanned at 16-20 weeks gestation
incidence at delivery is only 0.5%, therefore most placentas rise away from cervix
Placenta praevia Associated factors
multiparity
multiple pregnancy
embryos are more likely to implant on a lower segment scar from previous caesarean section
Placenta praevia causes fetal tachycardia
false
fetal heart usually normal
Placenta praevia commonly cause coagulation problems
false
coagulation problems rare
Placenta praevia sx
small bleeds before large shock in proportion to visible loss no pain uterus NOT tender lie and presentation may be abnormal
Investigations
placenta praevia
placenta praevia is often picked up on the routine 20 week abdominal ultrasound
the RCOG recommend the use of transvaginal ultrasound as it improves the accuracy of placental localisation and is considered safe
placenta praevia grading
I - placenta reaches lower segment but not the internal os
II - placenta reaches internal os but doesn’t cover it
III - placenta covers the internal os before dilation but not when dilated
IV - placenta completely covers the internal os
If low-lying placenta at 16-20 week scan mx
rescan at 34 weeks
no need to limit activity or intercourse unless they bleed
if still present at 34 weeks and grade I/II then scan every 2 weeks
if high presenting part or abnormal lie at 37 weeks then Caesarean section should be performed
Placenta praevia with bleeding mx
admit
treat shock
cross match blood
final ultrasound at 36-37 weeks to determine method of delivery, Caesarean section for grades III/IV between 37-38 weeks. If grade I then vaginal delivery
Prognosis placenta praevia
death is now extremely rare
major cause of death in women with placenta praevia is now PPH
Placental abruption describes
separation of a normally sited placenta from the uterine wall, resulting in maternal haemorrhage into the intervening space
Placental abruption occurs in approximately 1/200 pregnancies
true
Placental abruption causes
proteinuric hypertension cocaine use multiparity maternal trauma increasing maternal age
Placental abruption sx
shock out of keeping with visible loss pain constant tender, tense uterus normal lie and presentation fetal heart: absent/distressed coagulation problems
Placental abruption ms
Fetus alive and < 36 weeks
fetal distress: immediate caesarean
no fetal distress: observe closely, steroids, no tocolysis, threshold to deliver depends on gestation
Placental abruption mx
Fetus alive and > 36 weeks
fetal distress: immediate caesarean
no fetal distress: deliver vaginally
Placental abruption mx fetus dead
induce vaginal delivery
Placental abruption complications Maternal
shock
DIC
renal failure
PPH
Placental abruption complications fetal
IUGR
hypoxia
death
Placental abruption prognosis
associated with high perinatal mortality rate
responsible for 15% of perinatal deaths
Women who are at high risk of developing pre-eclampsia should take
aspirin 75mg od from 12 weeks until the birth of the baby.
Women who are at high risk of developing pre-eclampsia include?
hypertensive disease during previous pregnancies
chronic kidney disease
autoimmune disorders such as SLE or antiphospholipid syndrome
type 1 or 2 diabetes mellitus
The classification of hypertension in pregnancy is complicated and varies. Remember, in normal pregnancy blood pressure :
blood pressure usually falls in the first trimester (particularly the diastolic), and continues to fall until 20-24 weeks
after this time the blood pressure usually increases to pre-pregnancy levels by term
Hypertension in pregnancy in usually defined as:
systolic > 140 mmHg or diastolic > 90 mmHg
or an increase above booking readings of > 30 mmHg systolic or > 15 mmHg diastolic
Define Pre-existing hypertension
A history of hypertension before pregnancy or an elevated blood pressure > 140/90 mmHg before 20 weeks gestation
No proteinuria, no oedema
Define Pregnancy-induced hypertension
PIH, also known as gestational hypertension
Hypertension (as defined above) occurring in the second half of pregnancy (i.e. after 20 weeks)
No proteinuria, no oedema
Define Pre-eclampsia
Pre-eclampsia is a condition seen after 20 weeks gestation characterised by pregnancy-induced hypertension in association with proteinuria (> 0.3g / 24 hours). Oedema used to be third element of the classic triad but is now often not included in the definition as it is not specific
Epidemiology of
Pre-existing hypertension
gestational hypertension
Pre-eclampsia
Pre-existing hypertension: Occurs in 3-5% of pregnancies and is more common in older women
gestational hypertension: Occurs in around 5-7% of pregnancies
Pre-eclampsia: Occurs in around 5% of pregnancies
gestational hypertension often resolves folling birth
true
gestational hypertension increased risk of future ?
pre-eclampsia or hypertension later in life
Pre-eclampsia is important as it predisposes to the following problems
fetal: prematurity, intrauterine growth retardation
eclampsia
haemorrhage: placental abruption, intra-abdominal, intra-cerebral
cardiac failure
multi-organ failure
High risk factors - pre eclampsia
hypertensive disease in a previous pregnancy
chronic kidney disease
autoimmune disease, such as systemic lupus erythematosus or antiphospholipid syndrome
type 1 or type 2 diabetes
chronic hypertension
Moderate risk factors - pre eclampsia
first pregnancy age 40 years or older pregnancy interval of more than 10 years body mass index (BMI) of 35 kg/m² or more at first visit family history of pre-eclampsia multiple pregnancy
Features of severe pre-eclampsia
hypertension: typically > 170/110 mmHg and proteinuria as above
proteinuria: dipstick ++/+++
headache
visual disturbance
papilloedema
RUQ/epigastric pain
hyperreflexia
platelet count < 100 * 106/l, abnormal liver enzymes or HELLP syndrome
mx pre-eclampsia?
a woman at moderate or high risk of pre-eclampsia should take aspirin 75mg daily from 12 weeks gestation until the birth
consensus guidelines recommend treating blood pressure > 160/110 mmHg although many clinicians have a lower threshold
oral labetalol is now first-line following the 2010 NICE guidelines. Nifedipine (e.g. if asthmatic) and hydralazine may also be used
delivery of the baby is the most important and definitive management step. The timing depends on the individual clinical scenario
Eclampsia may be defined as
development of seizures in association pre-eclampsia. To recap, pre-eclampsia is defined as:
condition seen after 20 weeks gestation
pregnancy-induced hypertension
proteinuria
Why is Magnesium sulphate used to treat eclampsia
used to both prevent seizures in patients with severe pre-eclampsia and treat seizures once they develop.
Guidelines for magnesium sulphate in eclampsia?
should be given once a decision to deliver has been made
in eclampsia an IV bolus of 4g over 5-10 minutes should be given followed by an infusion of 1g / hour
treatment should continue for 24 hours after last seizure or delivery
What should be monitored when giving magnesium sulphate in eclampsia?
urine output, reflexes, respiratory rate and oxygen saturations should be monitored during treatment
Pre-eclampsia around ?% of seizures occur post-partum
around 40% of seizures occur post-partum)
Major complication and mx of this when
magnesium sulphate in eclampsia?
respiratory depression can occur: calcium gluconate is the first-line treatment for magnesium sulphate induced respiratory depression
important aspects of treating severe pre-eclampsia/eclampsia include
fluid restriction to avoid the potentially serious consequences of fluid overload
HELLP is
acronym for Hemolysis, Elevated Liver enzymes, and a Low Platelet count. It is a serious condition that can develop in the late stages of pregnancy. Whilst there is significant overlap with severe pre-eclampsia in terms of the features some patients present with no prior history so many specialists consider it a separate entity in its own right
?% of patients with severe preeclampsia will go on to develop HELLP.
10-20% of patients with severe preeclampsia will go on to develop HELLP.
HELLP SX
nausea & vomiting
right upper quadrant pain
lethargy
HELLP IX
bloods: Hemolysis, Elevated Liver enzymes, and a Low Platelet
HELLP MX
delivery of the baby
Antepartum haemorrhage is defined as
bleeding from the genital tract after 24 weeks pregnancy, prior to delivery of the fetus
vaginal examination should not be performed in primary care for suspected antepartum haemorrhage - why?
women with placenta praevia may haemorrhage
shock in proportion to visible loss - which placental issue?
Placenta praevia
pain constant - which placental issue?
Placental abruption
tender, tense uterus - Placenta praevia
false
Placental abruption
Bleeding in pregnancy differential 1st trimester
Spontaneous abortion
Ectopic pregnancy
Hydatidiform mole
Bleeding in pregnancy differential 2nd trimester
Spontaneous abortion
Hydatidiform mole
Placental abruption
Bleeding in pregnancy differential 3rd trimester
Bloody show
Placental abruption
Placenta praevia
Vasa praevia
Bleeding in pregnancy Alongside the pregnancy related causes, conditions such as sexually transmitted infections and cervical polyps should be excluded.
true
Types of spontaneous abortion?
Threatened miscarriage - painless vaginal bleeding typically around 6-9 weeks
Missed (delayed) miscarriage - light vaginal bleeding and symptoms of pregnancy disappear
Inevitable miscarriage - complete or incomplete depending or whether all fetal and placental tissue has been expelled.
Incomplete miscarriage - heavy bleeding and crampy, lower abdo pain.
Complete miscarriage - little bleeding
Typical picture of Ectopic pregnancy
Typically history of 6-8 weeks amenorrhoea with lower abdominal pain (usually unilateral) initially and vaginal bleeding later. Shoulder tip pain and cervical excitation may be present
Typical picture of Hydatidiform mole
Typically bleeding in first or early second trimester associated with exaggerated symptoms of pregnancy e.g. hyperemesis. The uterus may be large for dates and serum hCG is very high
Typical picture of Placental abruption
Constant lower abdominal pain and, woman may be more shocked than is expected by visible blood loss. Tender, tense uterus* with normal lie and presentation. Fetal heart may be distressed
Typical picture of Placental praevia
Vaginal bleeding, no pain. Non-tender uterus* but lie and presentation may be abnormal
Typical picture of Vasa praevia
Rupture of membranes followed immediately by vaginal bleeding. Fetal bradycardia is classically seen
Amniotic fluid embolism
Definition:
This is when fetal cells/ amniotic fluid enters the mothers bloodstream and stimulates a reaction which results in the signs and symptoms described below.
Amniotic fluid embolism - Epidemiology:
Rare complication of pregnancy associated with a high mortality rate
Amniotic fluid embolism aetiology
Many risk factors have been associated with amniotic fluid embolism but a clear cause has not been proven.
A consistent link has been demonstrated with maternal age and induction of labour.
It is widely accepted that maternal circulation must be exposed to fetal cells/ amniotic fluid in order for an amniotic fluid embolism to occur. However the precise underlying pathology of this process which leads to the embolism is not well understood, though suggestions have been made about an immune mediated process.
Amniotic fluid embolism sx & signs
Symptoms include: chills, shivering, sweating, anxiety and coughing.
Signs include: cyanosis, hypotension, bronchospasms, tachycardia. arrhythmia and myocardial infarction.
Amniotic fluid embolism occur when in pregnancy?
The majority of cases occur in labour , though they can also occur during caesarean section and after delivery in the immediate postpartum.
Amniotic fluid embolism diagnosis?
Clinical diagnosis of exclusion, as there are not definitive diagnostic tests.
Amniotic fluid embolism mx?
Critical care unit by a multidisciplinary team, management is predominantly supportive
Gestational trophoblastic disorders
Describes
spectrum of disorders originating from the placental trophoblast:
complete hydatidiform mole
partial hydatidiform mole
choriocarcinoma
Complete hydatidiform mole is?
Benign tumour of trophoblastic material. Occurs when an empty egg is fertilized by a single sperm that then duplicates its own DNA, hence the all 46 chromosomes are of paternal origin
Complete hydatidiform mole sx
bleeding in first or early second trimester
exaggerated symptoms of pregnancy e.g. hyperemesis
uterus large for dates
Complete hydatidiform mole ix
very high serum levels of human chorionic gonadotropin (hCG)
hypertension and hyperthyroidism* may be seen
Complete hydatidiform mole mx
urgent referral to specialist centre - evacuation of the uterus is performed
effective contraception is recommended to avoid pregnancy in the next 12 months
Complete hydatidiform mole Around ?% go on to develop choriocarcinoma
Around 2-3% go on to develop choriocarcinoma
In a partial mole what happens?
normal haploid egg may be fertilized by two sperms, or by one sperm with duplication of the paternal chromosomes. Therefore the DNA is both maternal and paternal in origin. Usually triploid - e.g. 69 XXX or 69 XXY. Fetal parts may be seen
