Complications of Pregnancy 1 Flashcards
What is abortion or spontaneous miscarriage?
Termination or loss of a pregnancy before 24 weeks gestation with no evidence of life
What is the incidence of spontaneous miscarriage?
Around 15%
What are the classes of miscarriage?
Threatened Inevitable Incomplete Complete Septic Missed
What is a threatened miscarriage?
Bleeding from the gravid uterus before 24 weeks gestation when there is a viable foetus and no evidence of cervical dilatation
- viable pregnancy
- vaginal bleeding +/- pain
- closed cervix
What is an inevitable miscarriage?
If cervix has already begun to dilate
- viable pregnancy
- open cervix with bleeding
What is an incomplete miscarriage?
Partial expulsion of the products of conception - always a risk of ascending infection into the uterus
- most of pregnancy expelled, some products of pregnancy remaining in uterus
- open cervix, vaginal bleeding (may be heavy)
What is a complete miscarriage?
Complete expulsion of the products of conception
- passed all products of conception
- cervix closed
- bleeding stopped
What is a septic miscarriage?
Ascending infection into the uterus which can spread throughout the pelvis
- especially in cases of incomplete miscarriage
What is a missed miscarriage?
Pregnancy in which the foetus has died but he uterus has made no attempt to expel the products of conception
Generally re-scan after 10-14 days to confirm missed miscarriage, as foetus may not be seen in early pregnancy
- gestational sac seen
- no clear foetus (empty gestational sac) or a foetal pole with no foetal heart seen in the gestational sac
What is the aetiology of spontaneous miscarriage?
Abnormal conceptus - chromosomal, genetic, structural
Uterine abnormality - congenital, fibroids
Cervical incompetence - primary, secondary
Maternal - increasing age, diabetes
Unkown
What is abnormal in a high proportion of pregnancies that abort?
Foetal development
What are the causes of abnormal foetal development?
Chromosomal, genetic or structural abnormalities within the foetus
Why is it often difficult in practise to identify the underlying factor responsible for abnormal foetal development and miscarriage?
Because changes in the foetal tissue after death interfere with chromosomal analysis or adequate structural examination
It is estimated from studies that what percentage of spontaneous miscarriages may be due to abnormal chromosomes?
up to 50%
What do congenital uterine abnormalities result from?
A failure of normal fusion of the Mullerian ducts
What percentage of the female population are affected by congenital uterine abnormalities?
Approximately 1%
What is the incidence of spontaneous miscarriage in women with congenital uterine abnormalities?
30% - double that of the normal population
What are commonly blamed as a cause of spontaneous miscarriage?
Fibroids - in particular sub mucous fibroids due to distortion of the uterine cavity
Why can incompetence of the cervix (particularly in the second trimester) be a cause of abortion?
When cervical incompetence is present, the cervic opens prematurely with absent or minimal uterine activity and the pregnancy is expelled
Why have hormonal imbalances been suggested as a cause of spontaneous abortion?
It has been shown that progesterone levels are lower in women with threatened miscarriage who proceed to have inevitable abortions compared to levels in those whose pregnancies continue
What maternal conditions are associated with an increased risk of spontaneous miscarriage?
SLE
Thyroid disease
Diabetes
Acute maternal infection e.g. pyelitis/appendicitis can cause a general toxic illness with high temperature which stimulates uterine activity and results in loss of pregnancy
What is an ectopic pregnancy?
A pregnancy implanted outside the uterine cavity
What is the incidence of ectopic pregnancy?
1 in 90 pregnancies
What are the risk factors for ectopic pregnancy?
Biggest risk factor is damaged Fallopian tube Pelvic inflammatory disease Previous tubal surgery Previous ectopic pregnancy Assisted conception
What is the presentation of ectopic pregnancy?
Period of amenorrhoea with positive urine pregnancy test (bleeding generally light)
Vaginal bleeding
Pain in abdomen
GI or urinary symptoms
What is the investigation of ectopic pregnancy?
Ensure woman is stable before starting investigations
Scan - will show no intrauterine gestational sac, may see adnexal mass, fluid in Pouch of Douglas
Serum BHCG levels - may need to serially track levels, sub-optimal rise in ectopic
Serum progesterone levels
What is the medical management of ectopic pregnancy?
Methotrexate - shrinkage of pregnancy tissue
What is the surgical management of ectopic pregnancy?
If pain and unstable
Mostly laparoscopic
Salpingectomy or salpingotomy
When might salpingotomy be indicated rather than salpingectomy?
In a woman who has had an ectopic previously and as a result has only one remaining Fallopian tube
What is the management of threatened miscarriage?
Conservative
What is the management of inevitable miscarriage?
May need evacuation if bleeding is heavy
What is the management of missed miscarriage?
Conservative - if woman is willing to wait for products of conception to be expelled naturally, can take weeks
Medical - prostaglandins (misoprostol)
Surgical
What is the management of septic miscarriage?
Antibiotics and evacuate uterus
What is antepartum haemorrhage?
Haemorrhage from the genital tract after the 24th week of pregnancy but before delivery of the baby
What is antepartum haemorrhage associated with?
Significant maternal and neonatal morbidity and mortality
What are the causes of antepartum haemorrhage?
Placenta praevia Placental abruption APH of unknown origin Local lesions of the genital tract Vasa praevia
What is placenta praevia?
Where all or part of the placenta implants in a lower segment of the uterus and lies in front of the presenting part of the foetus
1 in 200 pregnancies
When is placenta praevia more common?
Multiparous women
Multiple pregnancies
Previous C-section - placenta implants on CS scar
What is placental abruption?
Haemorrhage resulting from premature separation of the placenta from the uterine wall before the birth of the baby, associated with a retro-peritoneal clot
3% of all pregnancies
What does placental abruption depend on?
Maternal age
Parity
Social status
What is APH of unknown origin?
Includes haemorrhage where other causes have been completely excluded
What local lesions of the genital tract might cause antepartum haemorrhage?
Including lesions of cervix and vagina
- Cervical erosions and polyps
- Occasionally cervical cancer may present with APH
- Trichomonas or thrush infections within the vagina can occasionally cause a blood-stained discharge
What is vasa praevia?
Very rare but serious cause
Blood loss (usually small) due to rupture of a foetal vessel within the foetal membranes
- blood loss foetal, not maternal
- effect on foetus can be catastrophic
What is grade I placenta praevia?
Placenta encroaching on the lower segment but not the internal cervical OS
What is grade II placenta praevia?
Placenta reaches internal OS
What is grade III placenta praevia?
Placenta eccentrically covers the OS
What is grade IV placenta praevia?
Central placenta praevia
What is the presentation of placenta praevia?
Painless PV bleeding
Malpresentation of the foetus, soft non-tender uterus
Incidental finding
Maternal condition will correlate with amount of blood loss
What is the cause of bleeding in placenta praevia?
Separation of the placenta as the lower uterine segment forms and the cervix effaces
What are the features of blood loss in placenta praevia?
The blood loss occurs from the venous sinuses in the lower segment and is usually painless and recurrent
The amount of blood loss varies from minor to life-threatening haemorrhage
How is the diagnosis of placenta praevia usually made?
By ultrasound to locate placental site
Why are more errors encountered with posterior placenta praevia?
As it is more difficult to identify the posterior lower uterine segment
The bladder provides a good landmark anteriorly for the lower segment and diagnosis is more accurate with anteriorly placed placenta praevias
What does management of placenta praevia depend on?
Many factors including the gestation at presentation and severity of the blood loss
What is the management of placenta praevia?
Patient admitted to hospital
Vaginal examination contraindicated so diagnosis confirmed by US
Blood cross-matched and transfused depending on maternal conditions
Mother kept in hospital
Conservative approach to prolong pregnancy to gain foetal maturity
Delivery by Caesarean section
Risk of postpartum haemorrhage - drugs to control bleeding, risk of hysterectomy if bleeding cannot be controlled
What are the factors associated with placental abruption?
Pre-eclampsia/chronic hypertension Multiple pregnancy Polyhydramnios Smoking, increasing age, parity Previous abruption Cocaine use
What are the types of placental abruption?
Revealed
Concealed
Couvelaire uterus
Mixed
What is a revealed placental abruption?
Major haemorrhage apparent externally because blood released from the placenta exits through the cervical OS
What is a concealed placental abruption?
Haemorrhage occurs between placenta and uterine wall, uterine contents increased in volume and fundal height is larger than would be consistent for gestation
What is a mixed placental abruption?
Both concealed and revealed types of haemorrhage
What is Couvelaire uterus?
Concealed abruption when blood penetrates the uterine wall and uterus appears bruised
What is the general management of antepartum haemorrhage?
Management will vary from expectant treatment to attempting a vaginal delivery to immediate caesarean section depending on;
- amount of bleeding
- general condition of mother and baby
- gestation
What are the complications of placental abruption?
Maternal shock, collapse (may be disproportionate to amount of bleeding seen) Foetal death Maternal DIC, renal failure Postpartum haemorrhage Couvelaire uterus Risk of hysterectomy with huge bleeding
What is pre-term labour?
Onset of labour before 37 completed weeks gestation
32-36 weeks - mildly preterm
28-32 weeks - very preterm
24-28 weeks - extremely preterm
May be spontaneous or induced
What is the incidence of pre-term labour?
5-7% single pregnancy
30-40% multiple pregnancy
What are the predisposing factors for preterm labour?
Multiple pregnancy Polyhydramnios APH Pre-eclampsia Infection e.g. UTI Pre-labour premature rupture of membranes The majority are idiopathic
What is the general management of preterm delivery?
Confirm diagnosis - contractions with evidence of cervical discharge on VE
Consider possible causes e.g. abruption, infection
What is the management of preterm labour at 24-26 weeks?
Generally regarded as very poor prognosis
Decisions made in discussion with parents and neonatologists
What is the management of preterm labour of cases considered viable?
Consider tocolysis (stop/reduce uterine contractions) to allow steroids twice over 24 hours to stimulate foetal lung maturity, or to transfer to another unit if there is no bed for the mother and baby where they are
Steroids unless contraindicated
Transfer to unit with NICU facilities
Aim for vaginal delivery
What is preterm delivery a major cause of?
Perinatal mortality and morbidity, gestation dependent
What are the neonatal morbidities resulting from prematurity?
Respiratory distress syndrome Intraventricular haemorrhage Cerebral palsy Nutrition Temperature control Jaundice Infections Visual impairments Hearing loss
