Miscarriage: Definition & Incidence
Any pregnancy loss that occurs before 20 weeks gestation. Occurs in at least 15% of clinically recognised pregnancies 1 in 6. Most miscarriages occur in the first trimester.
Miscarriage: Causes
- Approximately 50% fetal losses in the first 8-15 weeks are due to aneuploidy (abnormal number of chromosomes).
- Many are due to abnormality at the time of conception or soon after
- Maternal conditions/illness
- Uterine and cervical complications such as ‘weak’ cervix, fibroids, congenital abnormality of the uterus
*Medications known as teratogens - Drug abuse
- Obesity, leptin, stress, excessive caffeine
- Age >36 years
*Unknown causes
Miscarriage: Types
- Threatened; there is some bleeding but the pregnancy may continue and 85% will have a normal outcome
- Inevitable (imminent); pregnancy will not continue and will proceed to incomplete/complete abortion
- Complete; products of conception are completely expelled.
- Incomplete is where the products of conception are partially expelled
- Anembryonic (blighted ovum); the fetus dies or fails to develop but the placental tissue continues to function. There may be no initial bleeding and may retain for several weeks before the placental tissue separates and bleeding starts.
- Missed; when the fetus dies but the woman’s cervix stays closed. There is no bleeding, the pregnancy is non-viable and this is confirmed on ultrasound.
- Recurrent miscarriage; 3 or more consecutive miscarriages before 20 weeks. Could be genetic causes, immunological factors, structural anomalies and infections.
Miscarriage: Diagnosis
- Confirmed by the woman’s story
- Observation of presenting signs and symptoms - pain, cramping, blood loss
- Physical examination
- Laboratory tests
- Ultrasonography
Miscarriage: Treatment
- Treatment is in accordance with the condition and type of miscarriage.
- Expectant management; uses the wait and see approach as 50% of women who have vaginal bleeding in the first trimester continue to have a viable pregnancy.
- Medical and surgical care; comprehensive history taking, confirmation of dates, ultrasound to determine viability, speculum, explanation and consent.
- Medical; Prostaglandin administration - may use oral or vaginal cervical preparation based on individual patient circumstance. For medical TOP and first trimester management of missed, incomplete and embryonic miscarriage. Non-invasive and cost effective.
- Mifepristone is available on PBS. Administered as a single 200mg oral dose, followed by an oral dose of 800 ug misoprostol 36-48 hours later. Effects are seen within 4 hours of administration of the second medication. 92% effective when used in pregnancies up to 49 days.
*Surgical care of miscarriage management often referred to as D&C (Dillitation and curettage), IV syntocinon is often started before the surgery to reduce blood loss and to decrease the risk of uterine perforation by causing the uterus to contract and thicken. Vacuum aspiration is preferred over sharp curettage in cases of incomplete miscarriage.
Other causes for vaginal bleeding
- Cervical carcinoma (1 in 6000) births. Most frequently diagnosed cancer in pregnancy. Treatable if detected early. 80% of cases detected in pregnancy are diagnosed in the first or second trimester. CIN is the precursor to invasive cancer of the cervix
- Cervical pathology, ectropion/erosion, polyps
- Varicosities of the cervix, vagina or vulva.
- Diagnostic error e.g. bleeding from the urinary tract or haemorrhoids.
- General maternal conditions - infections.
- Weakened cervix
Gestational trophoblastic disease (molar pregnancy)
Is a term covering both the benign hydatidiform mole and choriocarcinoma which is malignant.
Is the gross malformation of the trophoblast in which the chorionic vili are abnormal and become avascular
Gestational trophoblastic disease cause
Age <20 and >40
Environment
Genetic constitution
Poor nutrition
Previous molar 1:100 chance of reoccurrence
Gestational trophoblastic disease incidence
Rare
2:1000 in Asian women
0.57-1.1:1000 in Caucasian women
Gestational trophoblastic disease (Hydatidiform mole) types
Complete: develops from abnormal fertilisation and abnormal development of the placenta tissue. No evidence of an embryo or normal placental tissue.
Partial: Is associated with a fetus even if the only evidence is traces of a microscopic fetal circulation
Gestational trophoblastic disease (Hydatidiform mole) clinical features
Bleeding
Reduced platelets
Increased FDPs
Pallor and dyspnea
Anxiety and tremor
Uterine enlargement
Absent FHR
Absent fetal parts
Unexplained anemia
Molar pregnancy treatment
The aim of treatment is to remove all trophoblast tissue via surgical evacuation.
Serial bhCG every 1-2 weeks until 3 consecutive normal tests
Women should avoid conception until normal BhCG levels for 6 months
Follow up every 8 weeks for 12 months with urine pregnancy tests.
Treatment with chemotherapy in cases of myometrial invasion or evidence of trophoblastic metastases.
Ectopic pregnancy: Definition and incidence
A pregnancy in which implantation and the products of conception develop outside of the uterine cavity. Most commonly the fallopian tubes.
1-2% of all pregnancies
Ectopic pregnancy risk factors
- Previous tubal or pelvic infection/inflammation with residual endothelial damage
- Previous tubal or pelvic surgery
- Women who conceive with an IUD in situ
- ART
- Congenital tube abnormality
- Migration of the ovum
- Maternal cigarette smoking
Ectopic pregnancy signs and symptoms
Unruptured: Symptoms of early pregnancy with varying degrees of abdominal/pelvic pain
Ruptured: collapse and weakness, fast and weak pulse, hypotension, dizziness, hypovolaemia, acute abdominal/pelvic pain, abdominal distension, rebound tenderness and pallor, shoulder pain
Diagnosis of ectopic pregnancy
In the presence of constant cramp like pain, bleeding, shock and tenderness - determine ectopic via transvaginal U/S and blood tests.
Always suspect a tubal pregnancy until proven otherwise
Methotrexate
The treatment for an unruptured ectopic pregnancy by dissolution of the ectopic mass and results in resorption of the conceptus, aids in tubal preservation.
Cytotoxic thus caution regarding conception following treatment should be provided
Hyperemesis gravidaram: Definition and incidence
Excessive nausea and vomiting in pregnancy that begins between 4-10 weeks gestation and should resolve by 20 weeks.
Requires intervention and can lead to dehydration, starvation, electrolyte disturbance, weight loss
Incidence 0.3-3%
Hyperemesis risk factors
Multiple pregnancy
Molar pregnancy
High thyroxine levels
Chronic infection
Nutritional deficits
High pre-pregnancy fat intake
Hyperemesis management
Women who cannot retain food or fluids need to be admitted to hospital for assessment and management.
Assess physical condition: skin dryness, elasticity, rapid pulse, acetone breath and jaundice. IV infusion commenced
Investigations:
FBC
Urea and electrolytes
Liver function test
Thyroid function test
Urinalysis for ketones
Microscopy and culture
U/S
Anti-emetics, antihistamines, pyridoxine and oral steroids may be given.
Cervical insufficiency/incompetence/weak cervix: definition
Painless dilatation of the cervix in the second or early third trimester, often with bulging membranes through the cervix.
Cervical insufficiency Causes
Cervical trauma
D&C
TOP
Congenital weakness
History of cervical insufficiency
Cervical cerclage
Suture os put around the neck of the cervix around 14 weeks and left insitu until 38 weeks or at the onset of labour
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Complex care 123
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Module 9 Drugs: Complex care 118
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Module 8 Neonatal complications: Complex care 158
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Module 7: Complications in the third stage and perineal trauma13
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Module 6: Malpositions, malpresentations, disordered uterine action and pain in labour46
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Module 5: Preterm, PROM and multiple pregnancy24
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Module 4: Diabetes in the perinatal period20
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Module 3: bleeding in pregnancy18
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Module 2: Hypertensive disorders in the perinatal period10
