Womens Health (Ben) Flashcards
What is the definition of a Venous Thromboembolism (VTE) in Pregnancy?
- A VTE involves blood clots (thrombosis) developing within the circulation.
- When they form within the venous system this is known as a Deep Vein Thrombosis (DVT).
- The thrombosis can mobilise (embolisation) from the deep veins and travel to the lungs, where it becomes lodged in the pulmonary arteries, resulting in a pulmonary embolism (PE).
- Thrombosis occurs as a result of stagnation of blood as well as in hyper-coagulable states, such as in pregnancy, making it much more likely.
What is the epidemiology of VTEs in pregnancy?
- Pulmonary embolism is a significant cause of death in obstetrics.
- The risk is significantly reduced with VTE prophylaxis.
- The risk is highest in the postpartum period.
What are the risk factors for VTEs in Pregnancy?
- Smoking
- Parity ≥ 3
- Age > 35 years
- BMI > 30
- Reduced mobility
- Multiple pregnancy
- Pre-eclampsia
- Gross varicose veins
- Immobility
- Family history of VTE
- Thrombophilia
- IVF pregnancy
What medications are used for VTE prophylaxis?
Low Molecular Weight Heparin (LMWH):
* Enoxaparin
* Dalteparin
* Tinzaparin.
If Heparin is contraindicated, Mechanical prophylaxis may be used:
* Intermittent pneumatic compression (with equipment that inflates and deflates to massage the legs)
* Anti-embolic compression stockings
When does the RCOG advise starting VTE prophylaxis in pregnant women?
- 28 weeks if there are three risk factors
- First trimester if there are four or more of these risk factors
- It is stopped when the woman goes into labour but can be started again immediately after delivery (except with postpartum haemorrhage, spinal anaesthesia and epidurals)
- It is continued for 6 weeks postnatally.
VTE prophylaxis should also be given in the following situations regardless of risk factors:
* Hospital admission
* Surgical procedures
* Previous VTE
* Medical conditions such as cancer or arthritis
* High-risk thrombophilias
* Ovarian hyperstimulation syndrome
What is the clinical presentation of a Deep Vein Thrombosis (DVT)?
- Calf or leg swelling
- Dilated superficial veins
- Tenderness to the calf (particularly over the deep veins)
- Oedema
- Colour changes to the leg
Deep vein thrombosis is almost always unilateral
What is the clinical presentation of Pulmonary Embolism (PE)?
- Shortness of breath
- Cough with or without blood (haemoptysis)
- Pleuritic chest pain
- Hypoxia
- Tachycardia (this can be difficult to distinguish from the normal physiological changes in pregnancy)
- Raised respiratory rate
- Low-grade fever
- Haemodynamic instability causing hypotension
How are VTEs investigated?
DVTs:
* Diagnostic - Doppler Ultrasound
* The RCOG advices repeating negative ultrasound scans on day 3 and 7 in patients with a high index of suspicion for DVT.
PEs:
First Line - Chest XRay and ECG
Diagnostic - CT pulmonary angiogram (CTPA) or Ventilation-perfusion (VQ) scan.
Describe what CT pulmonary angiogram is
CT pulmonary angiogram involves a chest CT scan with an intravenous contrast that highlights the pulmonary arteries to demonstrate any blood clots.
This is usually the first choice for diagnostic of a PE (as opposed to a VQ Scan). This is the case because:
* It tends to be more readily available
* It provides a more definitive assessment
* It gives information about alternative diagnoses such as pneumonia or malignancy.
Describe what a Ventilation perfusion (VQ) scan is
- Ventilation-perfusion (VQ) scan involves using radioactive isotopes and a gamma camera, to compare the ventilation with the perfusion of the lungs.
- First, the isotopes are inhaled to fill the lungs, and a picture is taken to demonstrate ventilation. Next, a contrast containing isotopes is injected, and a picture is taken to demonstrate perfusion. The two images are compared.
- With a pulmonary embolism, there will be a deficit in perfusion, as the thrombus blocks blood flow to the lung tissue. This area of lung tissue will be ventilated but not perfused.
What are the possible complications of CTPAs and VQ Scans?
- CTPA carries a higher risk of breast cancer for the mother
- VQ scan carriers a higher risk of childhood cancer for the fetus
Why are D-Dimers not useful in pregnant women?
As pregnancy is a cause of a raised D-dimer. So it cannot be used to screen for DVTs and PEs.
What is the management of VTE in pregnancy?
Low molecular weight heparin (LMWH) (e.g. enoxaparin, dalteparin and tinzaparin).
* The dose is based on the woman’s weight at the booking clinic, or from early pregnancy.
* It should be started immediately, before confirming the diagnosis in patients where DVT or PE is suspected; as treatment can be stopped when the investigations exclude the diagnosis.
* LMWH is continued for the remainder of pregnancy, plus six weeks postnatally, or three months in total (whichever is longer).
* After giving birth, the mother can swap to oral anticoagulation (e.g. warfarin or a DOAC).
Massive PEs are a medical emergency, and treatment can involve:
* Unfractionated heparin
* Thrombolysis
* Surgical embolectomy
What is the definition of Gonorrhoea?
Gonorrhoea is a sexually transmitted infection (STI) caused by the gram-negative diplococcus, Neisseria gonorrhoeae.
What is the epidemiology of Gonorrhoea?
- It’s most prevalent among young adults, specifically those aged 15–24 years.
- Increased prevalence in men who have sex with men
What is the clinical presentation of Gonorrhoea?
Women
* Vaginal discharge
* Dysuria
* Abnormal vaginal bleeding
* Discharge from the cervical os, Skene’s gland or Bartholin’s gland may be observed.
Extragenital complications can also be observed:
* Pharyngitis
* Rectal pain an discharge
* Disseminated infection.
Men
* Often asymptomatic
* Discharge
* Dysuria
* Tender inguinal nodes
What are some differentials for Gonorrhoea?
-
Chlamydia trachomatis infection
Presents with similar symptoms such as discharge and dysuria, often co-infected with gonorrhoea. -
Trichomonas vaginalis infection
May present with pruritus, dysuria, and malodorous discharge. -
Bacterial vaginosis
Characterised by a fishy-smelling discharge, increased vaginal pH and positive ‘whiff’ test. -
Candidiasis
Symptoms include pruritus, burning sensation and thick, white, ‘cottage cheese’ like discharge.
How is Gonorrhoea diagnosed?
Diagnostic modalities include:
- Self-taken vulvovaginal swab in women
- Self-obtained rectal swab
- Clinician-obtained endocervical swab
- Microscopy revealing monomorphic Gram-negative diplococci within polymorphonuclear leukocytes
- Nucleic acid amplification tests (NAAT)
- Blood Culture
What is the management of Gonorrhoea?
First Line - Ceftriaxone
Following treatment, a test of cure is essential to monitor disease clearance and assess the effectiveness of the chosen antibiotic regimen.
What complications can Gonnorhoea cause during pregnancy?
- Increased risk of miscarriage and premature birth; due to pelvic inflammatory disease (PID).
- There can also be vertical transmission of gonorrhea between the mother and newborn baby during vaginal delivery.
- A neonatal gonorrhoea infection can cause severe eye infections.
- It can also cause future infertility
What is the definition of Chlamydia?
A genital chlamydia infection sexually transmitted infection caused by the obligate intracellular bacterium Chlamydia trachomatis.
What is the epidemiology of Chlamydia?
- It is the most common bacterial STI in the UK.
- Highest prevalence among young sexually active adults, specifically those aged 15 to 24 years
- Having multiple partners also increases the risk of catching the infection.
What is the clinical presentation of Chlamydia?
Chlamydia is very often asymptomatic (especially in women (75% of cases)). But it can cause:
* Abnormal (prurulent) vaginal discharge
* Pelvic pain
* Abnormal vaginal bleeding (intermenstrual or postcoital)
* Painful sex (dyspareunia)
* Painful urination (dysuria)
* Cervical motion tenderness (cervical excitation)
* Inflamed cervix (cervicitis)
Rectal chlamydia should be considered in patients with anorectal symptoms, such as:
* Discomfort
* Discharge
* Bleeding
* Change in bowel habits.
What are some differentials for Chlamydia?
The differentials mainly incude other STIs such as:
-
Gonorrhoea
Often asymptomatic but may cause urethral discharge, dysuria, intermenstrual or postcoital bleeding, and lower abdominal pain. -
Trichomoniasis
May cause pruritus, dysuria, and discharge in both men and women. -
Genital herpes
Characterised by painful vesicular lesions, dysuria, and flu-like symptoms.
How is chlamydia diagnosed?
Nucleic acid amplification tests (NAAT). Which can involve a:
- Vulvovaginal swab
- Endocervical swab
- First-catch urine sample (in women or men)
- Rectal swab (after anal sex)
- Pharyngeal swab (after oral sex)
What is the management of uncomplicated Chlamydia (not in pregnancy)?
First Line - doxycycline 100mg twice a day for 7 days
What is the management of Chlamydia during pregancy?
Doxycycline is contraindicated in pregnancy and breastfeeding. Alternatives include:
- Azithromycin 1g stat then 500mg once a day for 2 days
- Erythromycin 500mg four times daily for 7 days
- Erythromycin 500mg twice daily for 14 days
- Amoxicillin 500mg three times daily for 7 days
Should a test of cure be done after Chlamydia treatment?
No
Apart from in cases of:
* Rectal Chlamydia
* Pregnancy
* when Symptoms persist
What are the possible complications of Chlamydia during pregnancy?
- Preterm delivery
- Premature rupture of membranes
- Low birth weight
- Postpartum endometritis
- Ectopic pregnancy
- Neonatal infection (conjunctivitis and pneumonia)
What are the possible non-pregnancy related complications of Chlamydia?
- Pelvic inflammatory disease
- Chronic pelvic pain
- Infertility
- Epididymo-orchitis
- Conjunctivitis - is usually as a result of sexual activity, when genital fluid comes in contact with the eye.
- Lymphogranuloma venereum
- Reactive arthritis
What is the presentation of chlaydial conjunctivitis?
Symptoms last for longer than 2 weeks:
* Chronic erythema
* Irritation
* Discharge
Most cases are unilateral
It occurs more frequently in young adults. It can also affect neonates with mothers infected with chlamydia.
What is Lymphogranuloma venereum?
It is a condition affecting the lymphoid tissue around the site of infection with chlamydia. It most commonly occurs in men who have sex with men.
- Primary stage - Painless ulcer (primary lesion) that typically occurs on the penis in men, vaginal wall in women or rectum after anal sex.
- Secondary stage - lymphadenitis (swelling, inflammation and pain in the lymph nodes infected with the bacteria). The inguinal or femoral lymph nodes may be affected.
- Tertiary stage - inflammation of the rectum (proctitis) and anus. This leads to anal pain, change in bowel habit, tenesmus and discharge.
What is the management of Lymphogranuloma venereum?
1st Line - Doxycycline 100mg twice daily for 21 days
What is the definition of Syphilis?
Syphilis is a sexually transmitted infection caused by the spirochete bacterium Treponema pallidum.
What causes a Syphilis infection?
As stated, its caused by the bacterium Treponema pallidum. It can be transmitted by:
- Through direct contact with syphilis sores during sexual activity.
- Vertical transmission from an infected mother to her unborn child, resulting in congenital syphilis
- Intravenous drug use
- Blood transfusions and other transplants
What is the clinical presentation of Syphilis?
There are three stages of Syphilis:
Primary Syphilis
* A painless genital ulcer (chancre). That spontaneously recovers within 3 – 8 weeks. The lesion is round, with an indurated base.
* Local lymphadenopathy
Secondary Syphilis - Typically starts after the chancre has healed. (Or 4-10 weeks post-primary infection). Presents with:
* Symmetrical maculopapular rash, often involving the palms, soles, and face.
* Condylomata lata (grey wart-like lesions around the genitals and anus)
* Low-grade fever
* Lymphadenopathy
* Alopecia (localised hair loss)
* Oral lesions
Tertiary Syphilis - Can occur 20-40 years after the primary infection (in untreated patients). Presents with:
* Gummatous lesions (gummas are granulomatous lesions that can affect the skin, organs and bones)
* Aortic aneurysms
* Neurosyphilis
Neurosyphilis - can occur at any stage if the infection reaches the central nervous system. Presents with:
* Headache
* Altered behaviour
* Dementia
* Tabes dorsalis (demyelination affecting the spinal cord posterior columns)
* Ocular syphilis (affecting the eyes)
* Paralysis
* Argyll-Robertson pupil
What is an Argyll-Robertson pupil?
- It is a specific finding in neurosyphilis.
- It is a constricted pupil that accommodates when focusing on a near object but does not react to light.
- They are often irregularly shaped.
- It is commonly called a “prostitutes pupil” due to the relation to neurosyphilis and because “it accommodates but does not react“.
What is the presentation of Syphilis in Neonates?
It can present shortly after birth or later in infancy with:
* Rash on the palms/soles of feet
* Mucous patches/lesions in the mouth/nose/genitals
* Fever, hepatosplenomegaly
* Anaemia
* Bone developmental abnormalities (‘saber shins’)
* Neurological sequalae (seizures, developmental delay).
What are the investigations for Syphilis?
Different types of Serological testing is used for screening and monitoring, and then for confirmation of the diagnosis:
- Screening and Monitorring - Non-treponemal tests (e.g., VDRL, RPR)
- Diagnostic - treponemal tests (e.g., EIA, TPPA, FTA-ABS)
- Dark-field microscopy: Can be used to directly observe T. pallidum in samples from primary lesions or secondary rash.
- CSF examination: Should be considered in tertiary syphilis to evaluate for CNS involvement.
What is the management of Syphilis?
Primary, secondary, and early latent syphilis:
* A single dose of intramuscular penicillin G (benzathine benzylpenicillin) is the first-line therapy.
Tertiary and late latent syphilis or syphilis of unknown duration:
* Requires a longer course of intramuscular penicillin G for 2-3 weeks.
Neurosyphilis:
* Treated with intravenous penicillin G for 10-14 days
* Patients allergic to penicillin may be given doxycycline or tetracycline.
What is the definition of Bacterial Vaginosis?
Bacterial vaginosis is a bacterial imbalance of the vagina caused by an overgrowth of anaerobic bacteria and a loss of lactobacilli (the dominant bacterial species responsible for maintaining an acidic vaginal pH).
It is not a sexually transmitted infection but it increases the risk of developing an STI
What is the pathophysiology of Bacterial Vaginosis?
- Lactobacilli are the main component of the healthy vaginal bacterial flora. These bacteria produce lactic acid that keeps the vaginal pH low (under 4.5).
- The acidic environment prevents other bacteria from overgrowing.
- When there are reduced numbers of lactobacilli in the vagina, the pH rises. This more alkaline environment enables anaerobic bacteria to multiply.
What are the most common anaerobic bacteria associated with bacterial vaginosis?
- Gardnerella vaginalis (most common)
- Mycoplasma hominis
- Prevotella species
Bacterial vaginosis can occur alongside STIs like candidiasis, chlamydia and gonorrhoea.
What is the epidemiology of Bacterial Vaginosis?
It is the most common cause of abnormal vaginal discharge in women of childbearing age.
What are the risk factors of Bacterial Vaginosis?
- Multiple sexual partners (although it is not sexually transmitted)
- Excessive vaginal cleaning (douching, use of cleaning products and vaginal washes)
- Recent antibiotics
- Smoking
- Copper coil
- Pregnant women are at increased risk of bacterial vaginosis due to hormonal changes.
Bacterial vaginosis occurs less frequently in women taking the combined pill or using condoms effectively.
What is the presentation of Bacterial Vaginosis?
- fishy-smelling watery grey or white vaginal discharge (fishy smelling particularly after intercourse)
- Increased vaginal discharge
- Vaginal itching or irritation may be present but is less common
Half of women are asymptomatic
What are some differentials for Bacterial Vaginosis?
-
Vulvovaginal Candidiasis
Characterised by itching, burning, dyspareunia, and white, curd-like discharge. -
Trichomonas Vaginalis Infection
Presents with purulent, frothy, greenish discharge, pruritus, dyspareunia, and dysuria. -
Chlamydia or Gonorrhoea infection
May present with increased vaginal discharge and possibly lower abdominal pain, but are often asymptomatic. -
Atrophic Vaginitis
Most commonly seen in postmenopausal women, presenting with dryness, burning, dyspareunia, and thin, watery discharge.
How is Bacterial Vaginosis diagnosed?
The Amsel Criteria - Three out of the following 4 features need to be present:
* Vaginal pH >4.5 (Vaginal swab with pH paper)
* Homogenous grey or milky discharge
* Positive whiff test (addition of 10% potassium hydroxide produces a fishy odour)
* Clue cells present on wet mount (Microsopy)
What is the management of Bacterial Vaginosis?
- First line treatement - Metronidazole is given either orally or intravaginally.
- Second line management - Clindamycin
- Asymptomatic BV does not usually require treatment
You should also assess for the risk of STIs, as well as providing education about how to reduce the risk of recurrence.
What do patients on Metronidazole need to avoid?
Alcohol
This is because alcohol and metronidazole can cause a “disulfiram-like reaction”, with nausea and vomiting, flushing and sometimes severe symptoms of shock and angioedema.
What are the possible complications of Bacterial Vaginosis?
Increase the risk of catching sexually transmitted infections, including chlamydia, gonorrhoea and HIV.
During Pregnancy:
* Miscarriage
* Preterm delivery
* Premature rupture of membranes
* Chorioamnionitis
* Low birth weight
* Postpartum endometritis
What is the definition of Trichomoniasis?
Trichomoniasis is a sexually transmitted infection (STI) caused by the flagellated protozoan parasite, Trichomonas vaginalis.
It primarily infects the urogenital tract, and has an incubation period of around 7 days.
What is the epidemiology of Trichomoniasis?
It is the most common non-viral STI globally.
What is the clinical presentation of Trichomoniasis?
Women:
* Profuse, frothy, yellow-green vaginal discharge
* Vulval irritation
* Dyspareunia (painful sex)
* Asymptomatic presentation is also common (up to 50%)
* Strawberry Cervix sign may be seen on examination
* The vaginal pH will be raised (above 4.5) similar to bacterial vaginosis
Men
* Non-gonococcal urethritis
* Balanitis (inflammation to the glans penis)
* Also commonly asymptomatic
What can Trichomonas increase the risk of?
- Contracting HIV by damaging the vaginal mucosa
- Bacterial vaginosis
- Cervical cancer
- Pelvic inflammatory disease
- Pregnancy-related complications such as preterm delivery or low birth weight baby.
What are some differentials for Trichomonas?
-
Bacterial vaginosis
Characterized by a fishy-smelling, grayish-white vaginal discharge and vaginal pH > 4.5 -
Candidiasis
Presenting with a thick, white, “cottage cheese” like vaginal discharge and vulval itching -
Gonorrhea or Chlamydia
These STIs may present with mucopurulent cervical discharge, cervical motion tenderness, and may also be asymptomatic.
What investigations are done for Trichomonas?
- Diagnostic - Charcoal swab with microscopy
This should be taken from the posterior fornix of the vagina (behind the cervix) - Urethral swab or first catch urine is used in men
What is the management of Trichomonas?
Oral metronidazole
Either 400–500mg twice a day for 5–7 days, or a single dose of 2g orally.
Its advised to abstain from sexual activity for at least one week, or until the patient and all partners have completed treatment.
What is the definition of a Urinary Tract Infection?
Lower Urinary Tract Infection - Involves infection of the bladder, causing cystitis.
Upper Urinary Tract Infection - Involves infection up to the kidneys, called pyelonephritis.
What is the relationship between Pregancy and UTIs?
Pregnant women are at higher risk of developing both lower and upper UTIs
UTIs during pregnancy increase the risk of:
* Preterm delivery
* As well as other adverse pregnancy outcomes, like low birth weight and pre-eclampsia.
What is Asymptomatic Bacteriuria?
- Asymptomatic bacteriuria refers to bacteria present in the urine, without symptoms of infection.
- Pregnant women with asymptomatic bacteriuria are at a higher risk of developing UTIs, and subsequently at risk of preterm birth.
- As a result, pregnant women are tested at booking and routinely throughout pregnancy (urine sample testing for microscopy, culture & sensitivity).
- Urine testing of asymptomatic patients is not usually done (as it can lead to unescesary antibiotic use) but pregnant women are the exception due to the adverse outcomes associated with infection.
What is the presentation of a lower UTI?
- Dysuria (pain, stinging or burning when passing urine)
- Suprapubic pain or discomfort
- Increased frequency of urination
- Urgency
- Incontinence
- Haematuria
What is the presentation of an upper UTI (Pylonephritis)?
- Fever (more prominent than in lower urinary tract infections)
- Loin, suprapubic or back pain (this may be bilateral or unilateral)
- Looking and feeling generally unwell
- Vomiting
- Loss of appetite
- Haematuria
- Renal angle tenderness on examination
What investigation is routinely done in pregnant women to diagnose UTIs?
- Mid-stream urine samples are sent off for cultures and sensitivity testing.
What other investigations can be useful for investigating a UTI?
- Mid-stream urine (as stated above) - In children, men and pregnant women
- Urine Dipstick will be positive for nitrates and leukocytes (although this is unreliable in women older than 65 and those who are catheterised)
- Blood tests if there are signs of systemic upset (FBC, U+E, and CRP, etc…)
- Ultrasound scan of bladder/kidney (if there is concern about antecedents/complications (e.g.urinary retention/obstruction)
What are the most common causative organisms of UTIs?
- Escherichia coli (E. coli) (Most common)
- Klebsiella pneumoniae (gram-negative anaerobic rod)
- Enterococcus
- Pseudomonas aeruginosa
- Staphylococcus saprophyticus
- Candida albicans (fungal)
What is the management of UTIs in pregnancy?
Urinary tract infection in pregnancy requires 7 days of antibiotics
- First Line - Nitrofuratoin for 7 days (although this needs to be avoided in the 3rd trimester)
- Second Line - If nitrofuratoin is unsuitable then use Amoxicillin or Cefelexin for 7 days
Why does Nitrofuratoin need to be avoided during the 3rd trimester of pregnancy?
As it is associated with an increased a risk of neonatal haemolysis (destruction of the neonatal red blood cells).
Trimethoprim is a common alternative first line antibiotic for treatment of UTIs. Why can it not be given in pregnant women (especially in the first trimester)?
This is because it works as a folate antagonist. Folate is important in early pregnancy for the normal development of the fetus.
Trimethoprim in early pregnancy can cause congenital malformations, particularly neural tube defects (i.e. spina bifida). It is not known to be harmful later in pregnancy, but is generally avoided unless necessary.
What can occur if a pregnant woman becomes infected with the Varicella zoster virus (VZV)?
If a non-immune woman contracts the varicella zoster virus (VZV) during the first trimester of her pregnancy, it can cause Congenital varicella syndrome in the foetus (as the virus can have teratogenic effects).
What is the management of VZV during pregancy?
- If a non-immune pregnant woman comes into contact with a person infected with the VZV; immunoglobulin can be given as a preventive measure.
- If maternal infection by VZV occurs, Acyclovir is the treatment of choice and should be administered within 24 hours of the onset of the rash.
- Pregnant women who lack immunity to the VZV should be counseled to avoid exposure to the virus.
What is the definition of Premature ovarian insufficiency (POI)?
Premature ovarian insufficiency (POI) is a medical condition characterized by the onset of menopause in a woman aged below 40 years.
What can cause premature ovarian insufficiency?
The causes can either be idiopathic or iatrogenic e.g.:
* ovarian surgery
* radiotherapy or chemotherapy that directly impact the ovaries.
What is the clinical presentation of Premature ovarian insufficiency?
Women with POI typically develop the same symptoms as those undergoing natural menopause, including:
* Vasomotor symptoms:
Hot flushes, night sweats
* Sexual dysfunction:
Vaginal dryness, reduced libido, problems with orgasm, dyspareunia
* Psychological symptoms:
Depression, anxiety, mood swings, lethargy, reduced concentration
What are some differentials for Premature ovarian insufficiency?
-
Hypothyroidism:
Fatigue, weight gain, cold intolerance, depression, hair loss -
Hyperprolactinemia:
Irregular menstrual cycles, infertility, breast milk production not related to childbirth or nursing -
Polycystic Ovary Syndrome (PCOS):
Irregular periods, hirsutism, obesity, infertility
How is premature ovarian insufficiency diagnosed?
- Blood test for raised FSH levels; indicative of the menopause (repeated on at least 2 separate occasions)
What is the management of Premature ovarian insufficiency?
Hormone Replacement Therapy (HRT) until at least the age of normal menopause.
- HRT is done, unless the risks of HRT outweigh the benefits
- Psychological support should also be provided due to the potential mental health impacts of early menopause.
What is the definition of Oligohydramnios?
Oligohydramnios is defined as the presence of a lower than normal volume of amniotic fluid within the uterus.
What can cause Oligohydramnios?
There are various different causes:
* Uteroplacental insufficiency
This can lead to intrauterine growth restriction. Its usually due to maternal conditions like hypertension, pre-eclampsia, maternal smoking and placental abruption.
* Fetal urinary system abnormalities
The amniotic fluid is derived mainly from fetal urine, abnormalities in this system (such as renal agenesis, polycystic kidneys or urethral obstruction) can therefore lead to oligohydramnios.
* Premature rupture of membranes
* Post-term gestation
* Chromosomal anomalies
* Maternal use of certain drugs including prostaglandin inhibitors and ACE-inhibitors.
Was is the presentation of Oligohydramnios in the neonate?
Potter Syndrome which includes:
* Clubbed feet, facial deformity, congenital hip dysplasia (Due to foetal compression)
* Pulmonary hypoplasia (Due to lack of amniotic fluid)
Potter syndrome is largely the result of reduced ““space”” surrounding the fetus as well as the lack of amniotic fluid for fetal lung growth and development.
What is the main differential for Oligohydramnios?
Polyhydramnios - which is an overabundance of amniotic fluid.
How is Olighohydramnios diagnosed?
Diagnosis is made via ultrasound:
* This will show a reduced amniotic fluid index (AFI) or single deepest pocket (SDP)
What is the management of Oligohydramnios?
Management depends on the underlying aetiology; but options include:
-
Maternal rehydration
This may help to increase the amniotic fluid volume in mild cases of oligohydramnios. -
Amnioinfusion
This is the infusion of saline into the amniotic cavity to increase the volume of amniotic fluid. -
Delivery
In severe cases, or if the fetus is in distress, delivery may be the best option. This may be via induction of labour or caesarean section, depending on the clinical scenario.
What is the definition of Polyhydramnios?
Polyhydramnios is the presence of too much amniotic fluid within the uterus.
What is the aetiology of polyhydramnios?
The causes of polyhydramnios can be split into causes due to excessive production of amniotic fluid or insufficient removal of amniotic fluid:
Execessive production is caused by increased foetal urination which can be due to:
* Maternal diabetes mellitus
* Foetal renal disorders
* Foetal anaemia
* Twin-to-twin transfusion syndrome
Insufficient removal is caused by reduced foetal swallowing which can be due to:
* Oesophageal or duodenal atresia
* Diaphragmatic hernia
* Anencephaly
* Chromosomal disorders
What is the clinical presentation of polyhydramnios?
- A uterus that feels tense or is large for the date of gestation
- Difficulty of feeling foetal parts upon palpation of the abdomen.
What possible maternal complications can polyhydramnios cause?
Maternal complications:
- Maternal respiratory compromise due to increased pressure on the diaphragm
- Increased risk of urinary tract infections due to increased pressure on the urinary system
- Worsening of other symptoms associated with pregnancy such as gastro-oesophageal reflux, constipation, peripheral oedema and stretch marks
- Increased incidence of caesarean section delivery
- Increased risk of amniotic fluid embolism (although this is rare)
What possible foetal complications can polyhydramnios cause?
Foetal complications:
- Pre-term labour and delivery
- Premature rupture of membranes
- Placental abruption
- Malpresentation of the foetus (the foetus has more space to “move” within the uterus)
- Umbilical cord prolapse (polyhydramnios can prevent the foetus from engaging with the pelvis, thus leaving room for the cord to prolapse out of the uterus before the presenting part)
What is the management of polyhydramnios?
- Management of the underlying cause (e.g. maternal diabetes)
- Amnio-reduction in severe cases of polyhydramnios
What is the definition of foetal presentation?
Fetal presentation is the orientation of the fetus in the womb that determines which part of the fetus presents first at the pelvic inlet during childbirth.
What is the most common (and safest) foetal presentation?
Cephalic Vertex presentation
Makes up 95% of pregnancies
What is the definition of Malpresentation?
This is when the foetus is in a different orientation other than facing head-first down the pelvic inlet as birth approaches.
What is the most common type of malpresentation?
Breech Presentation - Refers to the positioning of the fetus in a longitudinal lie with the buttocks or feet proximal to the cervix and the head near the fundus.
What is the epidemiology of malpresentations?
Around 20% of babies are in breech presentation at 28 weeks gestation. But the vast majority of these revert to a cephalic presentation spontaneously, and only 3% are breech at term.
Other types of malpresentation (e.g. shoulder) are much rarer than breech presentations.
What are the 3 different types of Breech presentation?
- Complete (flexed) breech – both legs are flexed at the hips and knees (fetus appears to be sitting ‘crossed-legged’).
- Frank (extended) breech – both legs are flexed at the hip and extended at the knee. This is the most common type of breech presentation.
- Footling breech – one or both legs extended at the hip, so that the foot is the presenting part.
What are the risk factors for a Breech presentation?
Uterine:
* Multiparity
* Uterine malformations (e.g. septate uterus)
* Fibroids
* Placenta praevia
Foetal:
* Prematurity
* Macrosomia
* Polyhydramnios (raised amniotic fluid index)
* Twin pregnancy (or higher order)
* Abnormality (e.g. anencephaly)
What is the clinical presentation of a Breech presentation?
It is usually identified upon clinical examination:
* Upon palpation of the abdomen the round fetal head will be felt in the upper part of the uterus, and an irregular mass (fetal buttocks and legs) in the pelvis.
* The foetal heart may be auscultated higher on the maternal abdomen than usual
* Sometimes it’s not diagnosed until labour, where it can present with signs of foetal distress such as meconium-stained liquor.
Diagnosis of Breech presentation is of limited clinical significance before 32-35 weeks gestation; as most likely the foetus will revert to cephalic presentation by birth.
How is Breech presentation diagnosed?
Ultrasound Scan
What are some differentials for a breech presentation?
-
Oblique lie
The fetus is positioned diagonally in the uterus, with the head or buttocks in one iliac fossa. -
Transverse lie
The fetus is positioned across the uterus, with the head on one side of the pelvis and the buttocks on the other. The shoulder is usually the presenting part. -
Unstable lie
This is where the presentation of the fetus changes from day-to-day.
What is the management of a breech presentation?
-
External Cephalic Version (ECV)
This is the is the manipulation of the fetus to a cephalic presentation through the maternal abdomen. It is offered to primiparous women at 36 weeks, and to multiparous women at 37 weeks. There is a 50% success rate (40% in primiparous, 60% in multiparous); and if successful, it can enable an attempt at vaginal delivery. -
Caesarean Section
If ECV is unsuccessful, contraindicated, or declined by the woman, current UK guidelines advise an elective Caesarean delivery. -
Vaginal Breech Birth
Some women may still choose to aim for a vaginal breech delivery. A footling breech is contraindicated however as the feet and legs can slip through a non-fully dilated cervix, and the shoulders or head can then become trapped.
What are the possible complications for an ECV?
- Transient fetal heart abnormalities (which revert to normal),
- Persistent heart rate abnormalities (e.g fetal bradycardia)
- Placental abruption.
What are the complications of a breech presentation?
- Cord prolapse - where the umbilical cord drops down below the presenting part of the baby, and becomes compressed. This occurs in 1% of breech presentations (Compared to 0.5% in cephalic presentations)
Less common:
* Fetal head entrapment
* Premature rupture of membranes
* Birth asphyxia – usually secondary to a delay in delivery.
* Intracranial haemorrhage – as a result of rapid compression of the head during delivery.
What is the definition of Cephalopelvic disproportion?
Cephalopelvic disproportion occurs when there is mismatch between the size of the fetal head and size of the maternal pelvis, resulting in “failure to progress” in labor for mechanical reasons.
This is a significant risk factor for post term pregnancies
What is the definition of a Uterine Rupture?
- Uterine rupture is a complication of labour, where the muscle layer of the uterus (myometrium) ruptures.
- Uterine rupture leads to significant bleeding. The baby may be released from the uterus into the peritoneal cavity. It has a high morbidity and mortality for both the baby and mother.
What are the types of Uterine Rupture?
There are two types:
* Incomplete (or uterine dehiscence) rupture - The uterine serosa (perimetrium) surrounding the uterus remains intact.
* Complete rupture - The serosa ruptures along with the myometrium, and the contents of the uterus are released into the peritoneal cavity.
What are the risk factors for uterine rupture?
- Previous Caesarean section (The most significant)
- Vaginal birth after caesarean (VBAC)
- Previous uterine surgery
- Increased BMI
- High parity
- Increased age
- Induction of labour
- Use of oxytocin to stimulate contractions
Why does a previous caesarian section increase the risk of a uterine rupture?
- The scar on the uterus becomes a point of weakness, and may rupture with excessive pressure (e.g. excessive stimulation by oxytocin).
- It is extremely rare for uterine rupture to occur in a patient that is giving birth for the first time.
What is the clinical presentation of uterine rupture?
It presents with an acutely unwell mother. It may occur with induction or augmentation of labour with:
- Abdominal pain
- Vaginal bleeding
- Ceasing of uterine contractions
- Hypotension
- Tachycardia
- Collapse
What are some differentials of uterine rupture?
-
Placental abruption
Presents with abdominal pain +/- vaginal bleeding. The uterus is often described ‘woody’ and tense on palpation. -
Placenta praevia
Typically causes a painless vaginal bleeding. -
Vasa praevia
Characterised by a triad of ruptured membranes, painless vaginal bleeding, and fetal bradycardia.
What investigations are done to diagnose a uterine rupture?
- Intrapartum Cardiotocography (first line) - It is continuous recording of the fetal heart rate obtained via an ultrasound transducer placed on the mother’s abdomen. Changes in fetal heart rate pattern and prolonged fetal bradycardia are early indicators for uterine rupture.
- Ultrasound - Is diagnostic; features include abnormal fetal lie or presentation, haemoperitoneum and absent uterine wall.
What is the management of a uterine rupture?
- Uterine rupture is an obstetric emergency.
- Resuscitation and transfusion may be required.
- Emergency caesarean section is necessary to remove the baby, stop any bleeding and repair or remove the uterus (hysterectomy).
What is the definition of Preterm (or Premature) Labour?
- Preterm Labour - The onset of regular uterine contractions accompanied by cervical changes occurring before 37 weeks gestation.
- Preterm Birth - The delivery of a baby after 20 weeks gestation but before 37 weeks gestation.
Prematurity is classed as:
* Under 28 weeks: extreme preterm
* 28 – 32 weeks: very preterm
* 32 – 37 weeks: moderate to late preterm
What is the clinical presentation of Preterm labour?
Regular uterine contractions, changes in cervical effacement or dilation (before 37 weeks gestation)
What are some conditions associated with Preterm labour and delivery?
-
Overstretching of the uterus
Multiple pregnancy (commonly due to assisted conception) and polyhydramnios. -
Foetal risk conditions
Pre-eclampsia, intrauterine growth restriction, placental abruption. -
Uterus or cervical problems
Fibroids, congenital uterine malformation, short or weak cervix, previous uterine or cervical surgery. -
Infections
Chorioamnionitis, maternal or neonatal sepsis, bacterial vaginosis, trichomoniasis, Group B Streptococcus, sexually transmitted infections (e.g., Chlamydia), and recurrent urinary tract infections. -
Maternal co-morbidity
Hypertension, diabetes, renal failure, thyroid disease, etc.
What are some differentials for Preterm lecture?
-
Braxton Hicks contractions
Characterized by irregular, non-painful contractions that do not cause cervical dilation or effacement. -
Urinary tract infection
Presents with dysuria, frequency, suprapubic pain, and possibly preterm labour symptoms. -
Placental abruption
Presents with vaginal bleeding, abdominal pain, and hypertonic uterus. -
Uterine rupture
Signs include severe abdominal pain, vaginal bleeding, abnormal fetal heart rate, and cessation of contractions.
What investigations can be done when Preterm labour starts?
Foetal fibronectin test (fFN test) - is a screening test used to assess the risk of preterm delivery after the onset of pre-term labour.
A negative fFN test indicates a low risk of delivery occurring within the next 7-14 days.
What does the management of a Preterm labour involve?
- Corticosteroids - (betamethasone or dexamethasone) should be administered to accelerate foetal lung maturation.
- Intravenous antibiotics - if there is an increased risk of infection (evidence of Group B Streptococcus (GBS) in current or previous pregnancy, presence of maternal fever). (Penicillin is the antibiotic of choice if there is no allergy).
-
Tocolytic agents may be considered to delay labour, .
(Nifedipine is the first-line tocolytic agent).
What is the definition of Premature Rupture of the membranes (PROM)?
- PROM is a condition characterized by the rupture of the amniotic membranes (or sac) before the onset of labour.
- If this occurs after 37 weeks gestation, it is know as premature rupture of the membranes at term.
- If this occurs before 37 weeks however, it’s known as Preterm prelabour rupture of membranes (P‑PROM).
- Most women with PROM at term will spontaneously start labour within 24 hours.
What causes Premature Rupture of the membranes?
Exact cause isn’t well understood; but can be due to a combination of:
* Infection
* Inflammation
* Stress
* Mechanical forces.
What is the clinical presentation of Premature rupture of the membranes?
- Foul-smelling or greenish amniotic fluid
- Maternal fever
- Reduced foetal movements
A digital vaginal examination should be avoided in the absence of labour. But the foetal heart should be monitored.
What are some differentials for premature rupture of the membranes?
-
Urinary incontinence
This can be distinguished by the absence of amniotic fluid and the presence of urinary symptoms. -
Vaginal discharge or infection
This can be ruled out by the absence of foul-smelling or greenish discharge and the absence of other infection symptoms.
What investigations are done for premature rupture of the membranes?
Investigations for PROM should focus on assessing signs of infection and foetal distress, including:
- Monitoring maternal temperature
- Assessing foetal movements
- Monitoring foetal heart rate
- Observing vaginal discharge
What is the management of premature rupture of the membranes?
- If labour does not commence within 24 hours, induction of labour should be offered.
- If there are any signs of infection, immediate induction of labour should be commenced under consultant guidance and a broad spectrum antibiotic should be given.
- If there are any signs of foetal compromise, senior review is required to make a decision about whether immediate caesarean section is required.
- Following delivery, even if both baby and mother are asymptomatic, they should be closely observed in hospital for 12 hours post-birth.
What are some complications of premature rupture of the membranes?
- Chorioamnionitis - due to ascending infection
- Preterm birth - (and the associated complications) e.g. respiratory distress syndrome, necrotising enterocolitis, and foetal death
- Developmental problems - E.g. pulmonary hypoplasia, facial and limb deformities due to compression in the uterus, and cord prolapse due to low levels of amniotic fluid.
What is the definition of Umbilical cord prolapse?
- Cord prolapse is when the umbilical cord descends below the presenting part of the foetus and through the cervix into the vagina, after rupture of the fetal membranes.
- There is a significant danger of the presenting part compressing the umbilical cord, resulting in fetal hypoxia.
What are the risk factors of Cord Prolapse?
- Abnormal lie (Malpresentations) (e.g. transverse, breech)
- Multiple pregnancy
- Polyhydramnios
- High fetal head at delivery
- Multiparity
- Low birth weight
- Prematurity
What is the clinical presentation of Cord Prolapse?
- Sudden change in the fetal heart rate pattern, particularly variable or prolonged decelerations.
- Feeling of the cord in the vagina or visible cord after rupture of membranes
- Abnormal fetal heart rate detected on cardiotocography
How is a Cord prolapse diagnosed?
- Cardiotocography - Umbilical cord prolapse should be suspected when there are signs of foetal distress on CTG.
- Vaginal examination - Can then be used to diagnose a prolapsed cord (by confirming the presence of the umbilical cord in the birth canal)
What is the management of a Cord prolapse?
When cord prolapse is diagnosed, swift action is vital to prevent fetal hypoxia and death:
- Immediate delivery of the foetus is required (by Emergency Cesaerean section). A vaginal delivery has a high risk of cord compression and significant hypoxia to the baby.
- Use of the left lateral position (with a pillow under the hip) or the knee-chest position (on all fours) to prevent further prolapse. This uses gravity to draw the fetus away from the pelvis and reduce compression on the cord.
- Filling the bladder with 500ml warmed saline to aid in preventing further prolapse
- Avoidance of exposure and handling of the cord (as handling causes vasospasm)
- Use of tocolytics, (e.g.terbutaline), to stop uterine contractions.
What is the definition of an Instrumental Delivery?
Instrumental delivery refers to a vaginal delivery assisted by either a ventouse suction cup or forceps.
These tools are used to help in the delivery of the baby’s head.
What percentage of births are done by Instrumental Delivery?
10% of UK Births
What are the indications to perform an instrumental delivery?
- Failure to progress
- Foetal distress
- Maternal exhaustion
- Control of the head in various fetal positions
- The use of an epidural for analgaesia, increases the risk that an instrumental delivery may be nescesary.
What are the maternal risks of an instrumental delivery?
- Postpartum haemorrhage
- Episiotomy
- Perineal tears
- Injury to the anal sphincter
- Incontinence of the bladder or bowel
- Nerve injury (obturator or femoral nerve)
What are the foetal risks of an instrumental delivery?
- Cephalohaematoma with ventouse
- Facial nerve palsy with forceps
Rarer (more serious complications):
* Subgaleal haemorrhage (most dangerous)
* Intracranial haemorrhage
* Skull fracture
* Spinal cord injury
What is a Ventouse?
- It is essentially a suction cup on a cord.
- It goes on the baby’s head, and the doctor or midwife applies careful traction to the cord to help pull the baby out of the vagina.
- Its main complication is a cephalohaematoma - Which involves a collection of blood between the skull and the periosteum.
How are forceps used in an instrumental delivery?
- The forceps come as two pieces of curved metal that attach together, go either side of the baby’s head and grip the head in a way that allows the doctor or midwife to apply careful traction and pull the head from the vagina.
- Main complication is facial nerve palsy, with facial paralysis on one side.
- The forceps can also cause bruises on the baby’s face
What are the 2 nerves in the mother most commonly injured in an instrumental delivery?
- Femoral nerve
- Obturator nerve
The nerve injury tends to recover over 6 – 8 weeks.
How can the femoral nerve be injured during instrumental delivery?
The Femoral nerve can be compressed against the inguinal canal during a forceps delivery resulting in nerve injury.
What is the clinical presentation of a Femoral Nerve injury?
- Weakness of knee extension
- Loss of the patella reflex
- Numbness of the anterior thigh and medial lower leg.
How can the Obturator nerve be injured during instrumental delivery?
The obturator nerve may be compressed by forceps during instrumental delivery or by the fetal head during normal delivery.
What is the clinical presentation of a Obturator Nerve injury?
- Weakness of hip adduction and rotation
- Numbness of the medial thigh
What is the definition of Shoulder Dystocia?
- Shoulder dystocia is a specific type of obstructed labour where the anterior shoulder of the baby becomes stuck behind the pubic symphysis of the pelvis, after the head has been delivered.
- This is an obstectric emergency
What are the risk factors for Shoulder Dystocia?
- Maternal gestational diabetes
- Macrosomia
- Birthweight >4kg
- Advanced maternal age
- Maternal short stature or small pelvis
- Maternal obesity
- Post-dates pregnancy
What is the clinical presentation of Shoulder Dystocia?
- Difficult delivery of the foetal face or chin
- Retraction of the foetal head back into the vagina, after its been delivered (turtle-neck sign)
- Failure of restitution - where the head remains face downwards (occipito-anterior) and does not turn sideways as expected after delivery of the head.
- Failure of descent of the foetal shoulders following delivery of the head.
What is the management of Shoulder Dystocia?
Its an Obstetric emergency that needs prompt intervention to deliver the baby. There are various manouvres to help with this:
- McRoberts manoeuvre
- Rubins manoeuvre
- Wood’s screw manoeuvre
- Zavanelli manoeuver
An episiotomy can be used to enlarge the vaginal opening and reduce the risk of perineal tears. But this isn’t always nescesary.
