My Clinical Notes

See obstetric emergencies

• Placental abruption
• Placenta praevia
• Vasa praevia
• Pre-eclampsia

Premature labour

• Birth between 24 and 37 weeks (earlier births are referred to as miscarriages)
• Complicates 7% of UK pregnancies
• Babies born before 32 weeks account for more than half of all perinatal mortality
• Half the survivors at 23-25 weeks will have some degree of functional impairment
• Should be divided into,
  • Mildly preterm – 32-36 weeks
  • Very preterm – 28-32 weeks
  • Extremely preterm – 24-28 weeks

Aetiology

• Infection e.g. bacterial vaginosis, UTI
• Over-distention – multiple pregnancy and polyhydramnios
• Vascular – antepartum haemorrhage, blood irritates myometrium and weakens membranes
• Intercurrent illness – infective illnesses such as pyelonephritis, appendicitis, pneumonia
• Cervical weakness
• Idiopathic

Risk factors

• Previous preterm births
• Multiple pregnancy
• Cervical damage
• Fibroids
• Factors in current pregnancy
  • Recent antepartum haemorrhage
  • Intercurrent illness
  • Surgery
• Parity (0 or >5)
• Ethnicity – black women
• Poor socio-economic status
• Smoking
• Drugs of abuse especially cocaine
• Low body weight
• Inter-pregnancy interval of less that 1 year

Investigations

• Bedside fibronectin
• Cervical length measured by transvaginal ultrasound. A normal cervix measures around 35mm
• Repeat vaginal examination

Preterm pre-labour rupture of membranes (PPROM)

• Hx reporting ‘gush of fluid’ vaginally – must be distinguished from leaking urine
• Following rupture of membranes fetal movements will be reduced in strength/frequency
• Diagnosis can only be made following a speculum examination revealing a pool of fluid in the posterior vagina
• Vaginal examination should be avoided

Investigations

• Nitrazine testing – tests pH. Amniotic fluid is alkaline and vaginal secretions are acidic
• Genital tract swabs – helps guide antibiotic therapy
• Maternal well being – temp, BP, pulse
• Fetal well being – serial antepartum cardiotocography
• Ultrasound – amniotic fluid vol
• Amniocentesis – gram stain, microscopy, culture

Treatment

• Maternal steroids – reduces neonatal RDS
• Tocolytics – e.g. ritodrine is a beta2 agonist. Atosiban is an oxytocin antagonist, indomethacine. Can delay delivery giving time for steroid treatment and organisation of neonatal care
• Antibiotics – particularly after PPROM
• Caesarean section – at early gestation and oligohydramnios, lower uterine segment is often poorly formed. Riskier vertical uterine incisions are often required

Management of high-risk asymptomatic women

• Early dating scan
• Treatment of bacterial vaginosis
• Treatment of bacteruria
• Prophylaxis against Group B strep
• Cervical ultrasound to assess cervical length
• Fetal fibronectin testing – can only be undertaken after 23 weeks. High levels may be physiological before then

Malpresentation and Malposition

Breech presentation

• Presentation of the buttocks occurs in 3% of term pregnancies but is more common in early pregnancy and can complicate preterm deliveries
• Extended breech – both legs extended at the knee
• Flexed breech – both legs flexed at the knee
• Footing breech – one of both feet present below the buttocks

Aetiology

• No cause
• Prematurity
• Conditions that prevent fetal movement – e.g. twin pregnancy
• Conditions that prevent engagement of the head – placenta praevia, pelvic tumours, pelvic deformities

Complications

• Increase in perinatal and long term morbidity and mortality
• Higher incidence of neurological handicap
• Increase risk of cord prolapse
• Trapping of head upon delivery
• Cessation of progress of labour

Management

• External cephalic version (ECV)
  • Attempted after 37 weeks
  • Under ultrasound guidance
  • Risk of placental abruption and uterine rupture
• Caesarean section – safer than vaginal delivery

• Vaginal breech birth
  • More risky for large fetus or if there is evidence of fetal compromise
  • Important than fetal neck is flexed
  • Can result in slow dilatation and poor decent in second stage. Pushing is not advised until buttocks are visible
  • Requires an episiotomy after then buttocks distend the perineum
  • The fetus is as far as the umbilicus without traction
  • The legs can be flexed out of the vagina whilst the back is kept anterior
  • When the scapula is visible the arms can be hooked down by sweeping a finger over the shoulder and across the chest
  • Once the back of the neck is visible, the legs are held up whilst forceps are applied
  • With the next contraction the head is lifted slowly out of the vagina

Abnormal lie (transverse and oblique)

• Lie of the fetus defines the relationship of the fetus with the long axis of the uterus
• Occurs in 1 in 200 births but in more common earlier in pregnancy

Aetiology

• Preterm labour
• Conditions which allow more room to turn – polydramnios, lax uterus following multiparity
• Conditions which prevent turning –twin pregnancy
• Conditions which prevent engagement – placental praevia, pelvic tumours, uterine abnormalities

Complications

• Obstruction leading to uterine rupture

Management

• Caesarean section

This entry was posted on Saturday, September 29th, 2007 at 2:12 pm and is filed under Gynaecology/Obstetrics. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.