Women’s Health - Obestetrics Flashcards
What are the steps (5 key ones) to the examination of the pregnant abdomen?
SLeeP EAsy
- introduction, consent and pain?
- GI - previous ECS scar?
Palpation:
- symphyseal-fundal height
- the lie - how many poles can you feel in the fundus
- 1 - longitudinal - most common
- 2 - transverse (-) or oblique (\ /)
- the presentation- FACE FEET, ballot each pole, cephalic or breech
- head feels boney vs bottom feel softer
- the engagement - how many fifths?
- fetal back → auscultation anterior shoulder (110-160bpm)
Define antepartum haemorrhage and outline the main causes of it
Antepartum haemorrhage (APH) is defined as bleeding from or in to the genital tract, occurring from 24+0 weeks of pregnancy and prior to the birth of the baby.
- Occurs in 5% of pregnancies
Causes:
- No Identifiable cause in 40%
3 important causes:
- placenta praevia - painless bleeding
- placental abruption - painful bleeding
- Vasa praevia
- Infection
What is low lying placenta vs placenta praevia
Low-lying placenta is used when the placenta is within 20mm of the internal cervical os
Placenta praevia is used only when the placenta is over the internal cervical os. This is subdivided into partial and complete praevia (placenta completely covers the internal os)
Delivery of the placenta before baby is incompatible with survival.
How is placenta praevia diagnosed
Diagnosed at the routine 20-week anomaly scan - used to assess the position of the placenta and diagnose placenta praevia.
The scan is then repeated at 32 weeks (and 36 weeks) because the lower segment of the womb can stretch, if more than 2cm away from the internal os can avoid caesarian section
Many women with placenta praevia are asymptomatic. It may present with painless vaginal bleeding in pregnancy (antepartum haemorrhage). Bleeding usually occurs later in pregnancy (around or after 36 weeks).
Management of low lying placenta
Caesarian section - Planned delivery is considered between 36 and 37 weeks gestation. It is planned early to reduce the risk of spontaneous labour and bleeding. Planned cesarean section is required with placenta praevia and low-lying placenta (<20mm from the internal os).
Corticosteroids are given between 34 and 35 + 6 weeks gestation to mature the fetal lungs, given the risk of preterm delivery.
Advice:
- present if bleeding/pain
-avoid intercourse
- recurrent bleeding may require admission until delivery (remeber that lady in kings)
- anti-D if bleeding
KEY understanding - When is instrumental delivery indicated?
ONLY USED IN THE SECOND STAGE - if there is failure to progress (malpositioning, maternal exhuastion) or fetal distress
(failure to progress is after 2 hours in nulliparous women (one hour for decent, one hour pushing) or 1 hour pushing in multiparous.
If there is failure to progress or fetal compromise before 10cm then emergency CS is used. OMG this is key hun!
In general, the pre-requisites for performing an instrumental delivery are:
Fully dilated
Ruptured membranes
Cephalic presentation
Fetal head at least at the level of the ischial spines, and no more than 1/5 palpable per abdomen
What is vasa praevia? What are the two types?
Under normal circumstances, the umbilical cord containing the fetal vessels (umbilical arteries and vein) inserts directly into the placenta. The fetal vessels are always protected, either by the umbilical cord or by the placenta.
In vasa praevia, the fetal vessels are exposed, outside the protection of the umbilical cord or the placenta. The fetal vessels travel through the chorioamniotic membranes, and pass across the internal cervical os (the inner opening of the cervix). These exposed vessels are prone to bleeding, particularly when the membranes are ruptured during labour and at birth. This can lead to dramatic fetal blood loss and death.
There are two types of vasa praevia:
Type I vasa praevia – the fetal vessels are exposed as a velamentous umbilical cord (the umbilical cord inserts into the chorioamniotic membranes, and the fetal vessels travel unprotected through the membranes before joining the placenta)
Type II vasa praevia – the fetal vessels are exposed as they travel to an accessory placental lobe
Diagnosis of Vasa praevia
Vasa praevia may be diagnosed by ultrasound during pregnancy. This is the ideal scenario, as it allows a planned caesarean section to reduce the risk of haemorrhage. However, ultrasound is not reliable, and it is often not possible to diagnose antenatally.
It may present with antepartum haemorrhage, with bleeding during the second or third trimester of pregnancy.
It may be detected by vaginal examination during labour, when pulsating fetal vessels are seen in the membranes through the dilated cervix.
Finally, it may be detected during labour when fetal distress and dark-red bleeding occur following rupture of the membranes. This carries a very high fetal mortality, even with emergency caesarean section.
Management of Vasa praevia
For asymptomatic women with vasa praevia, the RCOG guidelines (2018) recommend:
Corticosteroids, given from 32 weeks gestation to mature the fetal lungs
Elective caesarean section, planned for 34 – 36 weeks gestation
Where antepartum haemorrhage occurs, emergency caesarean section is required to deliver the fetus before death occurs.
What are the three types of morbidly adherent placenta?
Placenta accreta spectrum refers to when the placenta implants deeper, through and past the endometrium, making it difficult to separate the placenta after delivery of the baby.
There are three distinctions:
- placenta accreta is where the placenta implants at the surface of the myometrium, but not beyond
- Placenta increta is where the placenta attaches deeply into the myometrium
- Placenta percreta is where the placenta invades past the myometrium and perimetrium, potentially reaching other organs such as the bladder
mnemonic: accreta - placenta is at the myometrium, intreat - placenta is in the myometrium, percreta is past the myometrium
Diagnosis and management of morbidly adherent placenta?
Ideally it is diagnosed on antenatal ultrasound scans -> Mx w/ early delivery by caesarian (35-37 weeks + antenatal steroids)
It may be diagnosed at birth, when it becomes difficult to deliver the placenta. It is a cause of significant postpartum haemorrhage
The options during caesarean are:
1. Hysterectomy with the placenta remaining in the uterus (recommended)
2. Uterus preserving surgery, with resection of part of the myometrium along with the placenta
3. Expectant management, leaving the placenta in place to be reabsorbed over time. Expectant management comes with significant risks, particularly bleeding and infection.
What happens if undiagnosed and not a caesarian?
What is placental abruption? how does it present?
Placental abruption refers to when the placenta separates from the wall of the uterus during pregnancy. The site of attachment can bleed extensively after the placenta separates. Placental abruption is a significant cause of antepartum haemorrhage.
Don’t confuse this with uterine rupture
Placental abruption refers to when the placenta separates from the wall of the uterus during pregnancy. The site of attachment can bleed extensively after the placenta separates. Placental abruption is a significant cause of antepartum haemorrhage.
The typical presentation of placental abruption is with:
- Sudden onset severe abdominal pain that is continuous
- Vaginal bleeding (antepartum haemorrhage)
- Shock (hypotension and tachycardia)
- Abnormalities on the CTG indicating fetal distress
- Characteristic “woody” abdomen on palpation, suggesting a large haemorrhage
- remember concealed abruption - cervical os remains closed and any haemorrhage remains in the uterus - maternal shock and pain appears disproportionate to the amount of bleeding
There is no test- US only rules out placenta praevia as a cause of bleeding.
Management of placental abruption
Placental abruption is an obstetric emergency. The urgency depends on the amount of placental separation, extent of bleeding, haemodynamic stability of the mother and condition of the fetus. It is important to consider concealed haemorrhage, where the vaginal bleeding may be disproportionate to the uterine bleeding.
Any woman presenting with a significant antepartum haemorrhage should be resuscitated using an ABCDE approach. Do not delay maternal resuscitation in order to determine fetal viability. IV access, fluids, tranfusion. CTG monitoring.
The ongoing management of placental abruption is dependent on the health of the fetus:
Emergency delivery – indicated in the presence of maternal and/or fetal compromise and usually this is by caesarean section unless spontaneous delivery is imminent or instrumental vaginal birth is achievable.
Antenatal steroids are offered between 24 and 34 + 6 weeks gestation to mature the fetal lungs in anticipation of preterm delivery.
Induction of labour – for haemorrhage at term without maternal or fetal compromise, induction of labour is usually recommended to avoid further bleeding.
Conservative management – for some partial or marginal abruptions not associated with maternal or fetal compromise (dependant on the gestation and amount of bleeding).
In all cases, give anti-D within 72 hours of the onset of bleeding if the woman is rhesus D negative. A Kleihauer test is used to quantify how much fetal blood is mixed with the maternal blood, to determine the dose of anti-D that is required.
Pre-eclampsia - Define:
- chronic hypertension
- pregnancy-induced hypertension
- pre-eclampsia
- severe pre-eclampsia
- eclampsia
Chronic hypertension is high blood pressure that exists before 20 weeks gestation and is longstanding. This is not caused by dysfunction in the placenta and is not classed as pre-eclampsia.
Pregnancy-induced hypertension or gestational hypertension is hypertension occurring after 20 weeks gestation, without proteinuria.
Pre-eclampsia is pregnancy-induced hypertension associated with organ damage, notably proteinuria.
Severe pre-eclampsia is pregnancy induced hypertension + proteinuria + neurological (headache, visual dirsturbance, clonus), hepatorenal (deranged LFTs, hepatomegaly, reduced platelets - HELLP), clotting
Eclampsia is when seizures occur as a result of pre-eclampsia.
severities of antepartum haemorrhage
The RCOG guideline (2011) defines the severity of antepartum haemorrhage as:
Spotting: spots of blood noticed on underwear
Minor haemorrhage: less than 50ml blood loss
Major haemorrhage: 50 – 1000ml blood loss
Massive haemorrhage: more than 1000 ml blood loss, or signs of shoc
Diagnosis of pre-eclampsia
The NICE guidelines (2019) advise a diagnosis can be made with a:
Systolic blood pressure above 140 mmHg
Diastolic blood pressure above 90 mmHg
PLUS any of:
Proteinuria (1+ or more on urine dipstick)
Organ dysfunction (e.g. raised creatinine, elevated liver enzymes, seizures, thrombocytopenia or haemolytic anaemia)
Placental dysfunction (e.g. fetal growth restriction or abnormal Doppler studies)
The NICE guidelines (2019) recommend the use of placental growth factor (PlGF) testing on one occasion during pregnancy in women suspected of having pre-eclampsia. Placental growth factor is a protein released by the placenta that functions to stimulate the development of new blood vessels. In pre-eclampsia, the levels of PlGF are low. NICE recommends using PlGF between 20 and 35 weeks gestation to rule-out pre-eclampsia.
Pathophysiology - by what mechanism does pre-eclampsia lead to eclampsia
This is a me card
Third spacing!!!
Third-spacing occurs when too much fluid moves from the intravascular space (blood vessels) into the interstitial or “third” space—the nonfunctional area between cells . This can cause potentially serious problems such as oedema, reduced cardiac output, and hypotension. Hypertension -> cerebral oedema -> seizure
yes interstitial fluid usually isn’t a problem, but here there is high pressure leading to too much interstitial fluid -> oedema
Pathophysiology of pre-eclampsia. How does pregnancy lead to hypertension?
Occurs after 20 weeks gestation - lacunae form in the placenta for exchange with chronic villi. When the process of forming lacunae is inadequate, the woman can develop pre-eclampsia. Pre-eclampsia is caused by high vascular resistance in the spiral arteries and poor perfusion of the placenta.
Background:
Trophoblast invades endometrium -> Endometrial spiral arteries break down and form lacunae (lakes) in the intervillous space. Maternal blood flows from the uterine arteries, into these lacunae, and back out through the uterine veins. Lacunae form at around 20 weeks gestation. These lacunae surround the chorionic villi (a bit like alveoli knots of fetal vessels) , separated by the placental membrane. Oxygen, carbon dioxide and other substances can diffuse across the placental membrane between the maternal and fetal blood.
Look at a diagram xx
Medical Management of pre-eclampsia, including prophylaxes
Aspirin is used for prophylaxis against the development of pre-eclampsia. It is given from 12 weeks gestation until birth to women with:
A single high-risk factor - chronic hypertension, previous pregnancy induced hypertension, autoimmune disease, diabetes, CKD
Two or more moderate-risk factors - maternal age over 40, BMI over 35, 10+ since previous pregnancy, first pregnancy, family history, multiple pregnancy
Medical management of pre-eclampsia is with:
- Labetolol is first-line as an antihypertensive
- Nifedipine (modified-release) is commonly used second-line
- methyldopa is third line
- IV magnesium sulphate is given during labour and in the 24 hours afterwards to prevent seizures
- Fluid restriction is used during labour in severe pre-eclampsia or eclampsia, to avoid fluid overload
Treating to aim for a blood pressure below 135/85 mmHg. Admission for women with a blood pressure above 160/110 mmHg. IV hydralazine may be used in severe pre-eclampsia
Planned early birth may be necessary if the blood pressure cannot be controlled or complications occur. (remember Lisa- birth is the only cure) Corticosteroids should be given to women having a premature birth to help mature the fetal lungs.
In women with pre-exsitng/chronic hypertension - management is the same as pregnancy induced hypertension. They need aspirin prophylaxis, treatment with labetalol -> nifedipine -> methyldopa. Treatment target is 135/85mmHg. Remeber ACE inhibitors are contraindicated, as are ARBs, thiazides.
Mx of eclampsia
Eclampsia refers to the seizures associated with pre-eclampsia. IV magnesium sulphate is used to manage seizures associated with pre-eclampsia.
What is maternal sepsis? What is septic shock?
What are the two causes of sepsis in pregnancy?
Sepsis is a condition where the body launches a large immune response to an infection, causing systemic inflammation and affecting the functioning of the organs of the body. It is still the leading cause of maternal death!
Severe sepsis is when sepsis results in organ dysfunction, such as hypoxia, oliguria or raised lactate. Septic shock is defined when arterial blood pressure drops (inflammation -> vasodilation) and results in organ hypo-perfusion.
Two key causes of sepsis in pregnancy are:
Chorioamnionitis
Urinary tract infections
Signs of sepsis, Signs of Chorio, Signs of UTI
The non-specific signs of sepsis include:
Fever
Tachycardia
Raised respiratory rate (often an early sign)
Reduced oxygen saturations
Low blood pressure
Altered consciousness
Reduced urine output
Raised white blood cells on a full blood count
Evidence of fetal compromise on a CTG
MEOWS - maternaity early obstetric warning sustem monitors for the signs of sepsis.
Additional signs and symptoms related to chorioamnionitis include:
Abdominal pain
Uterine tenderness - why Tess did the abdo examine on women with PROM
Vaginal discharge
Additional signs and symptoms related to a urinary tract infection include:
Dysuria
Urinary frequency
Suprapubic pain or discomfort
Renal angle pain (with pyelonephritis)
Vomiting (with pyelonephritis)
Management of maternal sepsis
Septic Six- BUFALO!
B- Blood cultures
U - Urine output
F- IV fluids
A - Empirical broad-spectrum antibiotics
L - Blood lactate level
O - oxygen to maintain sats 94-98%
Continous maternal and fetal monitoring (CTG) is required. Emergency C-section is indicated for signs of fetal distress.
Antibiotics used for maternal sepsis:
- piperacillin and tazobactam (tazocin) + gentamicin
- amoxicillin, clindamycin and genatimicin.
amoxicillin - gram positive coverage
Clinda - gram positive coverage
Gent - gram negative coverage.
Fetal compromise on CTG - what are early, late and prolonged decellarations? What is one significantly worrying sign on CTG
Early- vagus stimulation, these are normal
Late- hypoxia, fetus not coping
prolonged - compression of the cord
Early decelerations are gradual dips and recoveries in heart rate that correspond with uterine contractions. The lowest point of the declaration corresponds to the peak of the contraction. Early decelerations are normal and not considered pathological. They are caused by the uterus compressing the head the fetus, stimulating the vagus nerve of the fetus, slowing the heart rate.
Late decelerations are gradual falls in heart rate that starts after the uterine contraction has already begun. There is a delay between the uterine contraction and the deceleration. The lowest point of the declaration occurs after the peak of the contraction (they don’t line up!). Late decelerations are caused by hypoxia in the fetus, and are a more concerning finding. They may be caused by excessive uterine contractions, maternal hypotension or maternal hypoxia.
Prolonged decelerations last between 2 and 10 minutes with a drop of more than 15 bpm from baseline. This often indicates compression of the umbilical cord, causing fetal hypoxia. These are abnormal and concerning.
A sinusoidal CTG is a rare pattern to be aware of, as it can indicate severe fetal compromise. It gives a pattern similar to a sine wave, with smooth regular waves up and down that have an amplitude of 5 – 15 bpm. It is usually associated with severe fetal anaemia, for example, caused by vasa praevia with fetal haemorrhage.
A sinusoidal CTG is a rare pattern to be aware of, as it can indicate severe fetal compromise. It gives a pattern similar to a sine wave, with smooth regular waves up and down that have an amplitude of 5 – 15 bpm. It is usually associated with severe fetal anaemia, for example, caused by vasa praevia with fetal haemorrhage.
What is cord prolaspe?
biggest risk factor?
management?
Cord prolapse is when the umbilical cord descends below the presenting part of the fetus and through the cervix into the vagina, after rupture of the fetal membranes. There is a significant danger of the presenting part compressing the cord, resulting in fetal hypoxia.
The most significant risk factor for cord prolapse is when the fetus is in an abnormal lie after 37 weeks gestation (i.e. unstable, transverse or oblique). Being in an abnormal lie provides space for the cord to prolapse below the presenting part. In a cephalic lie, the head typically descends into the pelvis, without room for the cord to descend.
Management:
Emergency caesarean section is indicated where cord prolapse occurs. A normal vaginal delivery has a high risk of cord compression and significant hypoxia to the baby.
Pushing the cord back in is not recommended -> (handling causes vasospasm).
When the baby is compressing a prolapsed cord, the presenting part can be pushed upwards to prevent it compressing the cord. Woman lies in the left lateral position and Tocolytic medication (e.g. terbutaline) can be used to minimise contractions
What is a post-partum haemorrhage. What are the two types? What are the main causes?
Postpartum haemorrhage (PPH) refers to bleeding after delivery of the baby and placenta. It is the most common cause of significant obstetric haemorrhage, and a potential cause of maternal death (but not baby- antepartum with praevias and abruption…)
500ml after a vaginal delivery
1000ml after a caesarean section
It can also be categorised as:
Primary PPH: bleeding within 24 hours of birth
Secondary PPH: from 24 hours to 12 weeks after birth
There are four causes of postpartum haemorrhage, remembered using the “Four Ts” mnemonic:
T – Tone (uterine atony – the most common cause)
T – Trauma (e.g. perineal tear)
T – Tissue (retained placenta) - this is the secondary cause, the others are primary usually
T – Thrombin (bleeding disorder)
Management of post-partum haemorrhage
Treat the Cause - 4 Ts:
Stopping the bleeding:
- mechanical stimulation (rubbing) the uterus
- catheritisation (full bladder prevents contraction)
Medical:
- syntocinon
- Ergometrine - stimulates smooth muscle contraction
- carboprost (haemobate- prostoglandin analogue -> contraction)
-tranexamic acid (anti-fibrinolytic)
- Misoprostol
Surgical treatment options involve:
Intrauterine balloon tamponade – inserting an inflatable balloon into the uterus to press against the bleeding
B-Lynch suture – putting a suture around the uterus to compress it
Uterine artery ligation – ligation of one or more of the arteries supplying the uterus to reduce the blood flow
Hysterectomy is the “last resort” but will stop the bleeding and may save the woman’s life
Secondary post-partum haemorrhage:
Secondary postpartum haemorrhage is where bleeding occurs from 24 hours to 12 weeks postpartum. This is more likely to be due to retained products of conception (RPOC) or infection (i.e. endometritis).
Investigations involve:
Ultrasound for retained products of conception
Endocervical and high vaginal swabs for infection
Management depends on the cause:
Surgical evaluation of retained products of conception
Antibiotics for infection
What is the only known cause of shoulder dystocia? 4 complications?
1% of vaginal births
Shoulder dystocia is when the anterior shoulder of the baby becomes stuck behind the pubic symphysis of the pelvis, after the head has been delivered. This requires additional obstetric manoeuvres to enable delivery of the rest of the body.
Shoulder dystocia is an obstetric emergency:
The key complications of shoulder dystocia are:
Fetal hypoxia (and subsequent cerebral palsy)
Brachial plexus injury and Erb’s palsy
Perineal tears
Postpartum haemorrhage
Shoulder dystocia is often caused by macrosomia secondary to gestational diabetes.
presentation - not testing just a reminder:
Shoulder dystocia presents with difficulty delivering the face and head, and obstruction in delivering the shoulders after delivery of the head. There may be failure of restitution, where the head remains face downwards (occipito-anterior) and does not turn sideways as expected after delivery of the head. The turtle-neck sign is where the head is delivered but then retracts back into the vagina.
Management of Shoulder dystocia (5 steps)
External manoeuvres:
1. McRoberts manoeuvre involves hyperflexion of the mother at the hip (bringing her knees to her abdomen). This provides a posterior pelvic tilt, lifting the pubic symphysis up and out of the way - 90% resolve here
- Pressure to the anterior shoulder involves pressing on the suprapubic region of the abdomen. This puts pressure on the posterior aspect of the baby’s anterior shoulder, to encourage it down and under the pubic symphysis. (backs to maternal right/left - want to push on the back of the sholder)
Then internal manoeuvres:
3. rotational manoeuvre (rubins) - hands inside vagine push posterior aspect of anterior sholder and anterior aspect of posterior cholder to twist shoulders under the pubic synthesis
4. remove the posterior arm
- If internal manoeuvres fail - Zavanelli manoeuver involves pushing the baby’s head back into the vagina so that the baby can be delivered by emergency caesarean section.
What are the three stages of labour? What is partogram used for?
First stage (until 10cm dilation of the cervix) - subdivided into:
- latent first stage (up until 4cm)
-active first stage (active labour) (from 4cm-10cm)
Second stage - 10cm to delivery of the fetus
Third stage - from delivery of the fetus to delivery of the placenta
Partogram is for the First stage only! (remember second stage- pushing takes 1/2 hours)
Women are monitored for their progress in the first stage of labour using a partogram - cervical dilation nd fetal head dissent recorded amongst other things. Crossing the alert line is an indication for amniotomy (artificially rupturing the membranes) and a repeat examination in 2 hours. Crossing the action line means care needs to be escalated to obstetric-led care and senior decision-makers for appropriate action.
What is the main complication of placenta praevia and how is it managed? (5 Mx options)
The main complication of placenta praevia is haemorrhage before, during and after delivery. When this occurs, urgent management is required and may involve:
Emergency caesarean section
Blood transfusions
Intrauterine balloon tamponade
Uterine artery occlusion
Emergency hysterectomy
How long should the second stage of labour last?
The success of the second stage depends on “the three Ps”: power, passenger and passage. Delay in the second stage is when the active second stage (pushing) lasts over:
2 hours in a nulliparous woman
1 hour in a multiparous woman
What is involved in active management of the third stage of labour?
Active management involves intramuscular oxytocin and controlled cord traction.
Management of Failure to Progress (4 options)
The main options for managing failure to progress are:
- Amniotomy, also known as artificial rupture of membranes (ARM) for women with intact membranes
- Oxytocin infusion
- Instrumental delivery
- Caesarean section
remember this is both first and second stage
Oxytocin is used first-line to stimulate uterine contractions during labour. It is started at a low rate and titrated up at intervals of at least 30 minutes as required. The aim is for 4 – 5 contractions per 10 minutes. Too few contractions will mean that labour does not progress. Too many contractions can result in fetal compromise, as the fetus does not have the opportunity to recover between contractions.
The condition of the fetus needs to be monitored throughout labour and delivery. Fetal compromise may mean delivery needs to be expedited, or example, with emergency caesarean section.
Physiology of the second stage of labour -
- the 7 cardinal movements?
Why these movements - key understanding
There are seven cardinal movements of labour:
Engagement
Descent
Flexion
Internal Rotation
Extension
Restitution and external rotation
Expulsion
Explanation
- the pelvic inlet is widest side to side, the pelvic outlet is widest front to back
- the fetal skull is widest front to back (sagittally)
- enters the pelvic inlet Occiput tranverse so that the widest part of the skull aligns with the widest part of the pelvis, then internally rotates to exit at the pelvis outlet
- flexion of the head (chin to chest) - reduces the diameter of the head, if baby is OP this also increases diameter because baby can’t flex
- extend head around the pubic synthesis
-external rotation because shoulders are wider (not as long as the head sagittally, but wider than it coronally)
