Non-Viable Pregnancies Flashcards
What is defined as a miscarriage?
The spontaneous expulsion of the products of conception before 24 weeks gestation
What is the epidemiology surrounding miscarriage?
It occurs in 15-20% of clinical pregnancies.
75% of all miscarriages occur in the first 12 weeks
What are the possible causes for a miscarriage?
Maternal:
General:
- Age
- Obesity
- Acute febrile illness
- Septicaemia
- Severe hypertension
- Renal disease
- Diabetes
- Hypothyroidism
- Trauma
- Surgical operation
Local:
- Uterine fibroids
- Congenital uterine malformations
- Incompetent internal os
- Hormone deficiency
Foetal:
- Congenital and genetic malformations (miscarriage by 8 weeks)
- Faulty implantation
What are the different types of miscarriage?
- Threatened
- Inevitable
- Missed
- Incomplete
- Complete
What is a threatened miscarriage? What is the clinical presentation of it? How is it managed?
What other types of miscarriage are there?
A threatened miscarriage is bleeding from the genital tract before 24 weeks.
Pain: usually absent Bleeding: scanty, brown or bright red Breasts: may still be active Uterine size: normal for gestational age Cervical os: closed USS: foetal heart sounds present
A threatened miscarriage is managed with rest and limited exertion. Women are advised to avoid intercourse for the first 12 weeks of pregnancy.
Other types of miscarriage:
- Inevitable
- Missed
- Incomplete
- Complete
What is a inevitable miscarriage? What is the clinical presentation of it? How is it managed?
What other types of miscarriage are there?
An inevitable miscarriage refers to the presence of an open internal os, with bleeding. Usually, products are not completely expelled.
A threatened miscarriage can turn into an inevitable miscarriage if dilatation occurs.
Pain: severe pelvic cramping Bleeding: heavy with clots and tissue Breasts: - Uterine size: as expected for dates Cervical os: open USS: foetal heart sounds present/absent
An inevitable miscarriage is managed depending on the gestations:
<12 weeks: uterus evacuated under GA
>12 weeks: spontaneous evacuation is waited for. Potentially, misoprostol given (5 units or 0.5mg)
Other types of miscarriage:
- Threatened
- Missed
- Incomplete
- Complete
What is a missed miscarriage? What is the clinical presentation of it? How is it managed?
What other types of miscarriage are there?
Here, the embryo dies in early development and is absorbed. All that is left is a sac. The sac MUST be over 25mm for this diagnosis.
Pain: none Bleeding: none or minimal Breasts: soft Uterine size: - small for dates Cervical os: closed USS: no foetal heart sound or products of conception
A missed miscarriage is managed depending on the gestational size of the sac:
<8 weeks: expectant management with regular follow-up until miscarriage is complete
> 8 weeks:
- Surgical evacuation
- Medical treatment with oral prostaglandins every 3 hours (successful in 50% of cases)
Other types of miscarriage:
- Threatened
- Inevitable
- Incomplete
- Complete
What is an incomplete miscarriage? What is the clinical presentation of it? How is it managed?
What other types of miscarriage are there?
This occurs when some of the retained products of conception are expelled, and some is not.
Pain: yes/no
Bleeding: heavy with clots
Breasts: -
Uterine size: small or as expected for age
Cervical os: open
USS: no foetal heart sound, some retained products of conception
An incomplete miscarriage is managed with evacuation of the uterus contents.
Other types of miscarriage:
- Threatened
- Inevitable
- Missed
- Complete
What is a complete miscarriage? What is the clinical presentation of it? How is it managed?
What other types of miscarriage are there?
A complete miscarriage is when the entire contents of the uterus are expelled. This usually occurs before 8 weeks gestation. This requires a PREVIOUSLY SEEN pregnancy on ultrasound.
Pain: no Bleeding: minimal Breasts: - Uterine size: small or as expected Cervical os: open/closed USS: no foetal heart sound and uterus is empty
A complete miscarriage requires no management except that an ectopic pregnancy is excluded.
Other types of miscarriage:
- Threatened
- Inevitable
- Missed
- Incomplete
What investigations should be performed in a suspected case of miscarriage?
- Transvaginal Ultrasound
- Beta hCG (should double every 48 hours in a viable pregnancy)
- Progesterone
- Bloods: FBC and rhesus
- Triple swabs (if pyrexial)
What is the definition of recurrent miscarriage?
Three or more consecutive miscarriages
What is the epidemiology surrounding recurrent miscarriage?
Approximately 1% of all women are affected.
What are the causes for recurrent miscarriage?
50% of all cases have no known causes
Of those with a known cause:
- Polycystic ovaries (50%)
- Antiphospholipid syndrome (40%)
- Cervical incompetence (5%) [trauma, previous difficult labour, repeated dilatation, operations]
- Congenital uterine abnormalities (1%)
- Genetic causes (3%)
- Bacterial vaginosis
What are the risk factors associated with recurrent miscarriage?
- Advanced maternal age
- Previous miscarriage
What investigations should be performed in a case of recurrent miscarriages?
- Maternal pelvic USS
- Maternal anti-phospholipid antibody screen (measure APS lupus anticoagulant and anticardiolipin antibodies)
- Bacterial vaginosis screen
- Cytogenic analysis of foetal tissue
- Parental karyotype
What is the management of recurrent miscarriage?
- Psychological counselling
- Genetic counselling
- Abstain from exertion/intercourse/travelling until after 14 weeks
- Pregnancy should be closely monitored with US
- Late miscarriage due to cervical incompetence: cervical suturing can help
- Antiphospholipid syndrome: give aspirin and heparin during pregnancy (improves take-home baby rate from 10% to 40%)
In miscarriage, what is the likelihood of the next pregnancy resulting in a live birth?
First miscarriage: 85%
Second miscarriage: 75%
Third or more: 60%
Unless the diagnosis is antiphospholipid syndrome:
With no treatment: 10%
With aspirin and heparin: 40%
What is an ectopic pregnancy?
This is where the embryo implants outside the uterine cavity. It can implant in a large array of places and these include:
- Fallopian tubes (most common)
- Ovary
- Cervix
- Abdominal cavity
- Broad ligament
What is the epidemiology surrounding ectopic pregnancies?
They occur at a rate of 0.5% in the UK
What can cause an ectopic pregnancy?
Normally, the fertilised ovum travels to the uterus over 5 days. Anything which delays this process, can result in an ectopic pregnancy.
Causes include:
- IUD
- Progesterone pill
- Congenital uterine anomaly
What are the risk factors of ectopic pregnancy?
- PID
- Previous pelvic surgery
- Previous ectopic pregnancy
- IUD
- Progesterone only pill
- Emergency contraception
- History of subfertility
- Increasing maternal age
What is the pathophysiology surrounding ectopic pregnancies?
The muscular walls of the fallopian tubes cannot allow a pregnancy to grow. Therefore, one of the following occur:
- Absorption: the tube fully absorbs the pregnancy and little bleeding occurs
- Tubal abortion: the products of conception are expelled from the tube into the peritoneal cavity
- Tubal rupture: most dramatic but least common. The tube ruptures and causes and acute abdominal episode
- Secondary abdominal pregnancy: the embryo implants elsewhere in the abdominal cavity; it can grow to term.
What are the clinical features of an ectopic pregnancy?
History:
- Amenorrhoeic
- Pain: colicky, possible shoulder pain (phrenic nerve activation from blood in abdominal cavity)
- Vaginal bleeding (scanty, severe if rupture)
- Syncope (blood loss)
Examination:
- Signs of shock (if ruptured) [tachycardia, hypotension, pallor)
- Abdominal tenderness and rebound tenderness
- Unilateral adnexal tenderness
What are the differences in examination in an unruptured and ruptured ectopic pregnancy?
Unruptured:
- Uterus slightly enlarged
- Displaced uterus
Ruptured:
- Pallor, hypotension, tachycardia
- Extremely tender uterus
What investigations are ordered in a possible case of ectopic pregnancy?
One follows the management algorithm for ectopic pregnancy
- Pregnancy test (always positive)
- Transvaginal ultrasound (if inconclusive and stable, perform serial beta hCG)
- Serum beta hCG (every 48 hours)
If beta hCG is >1500; medical management
If beta hCG is <1500; US repeated once it is above 1500
- Progesterone levels (will be less than 20 in a non-viable pregnancy)
- Laparoscopy (best way to visually diagnose)
What are the differential diagnoses in a case of ectopic pregnancy?
- Inevitable miscarriage
- Bleeding with ovarian cyst
- Pelvic appendicitis
- Acute salpingitis
- Other acute abdominal catastrophe
What is the management of ectopic pregnancy?
Initial management:
- Admission
- NBM and IV fluids
- FBC and cross-match
- Rhesus state
Medical management: Consider if: - Beta hCG is <3000 - Embryo is <3cm - No signs of rupture - No altered renal/liver function
Prescribe methotrexate at a dose of 50mg/m^2 of surface area
Measure hCG at days 4 and 7 to check it is falling
Advise on contraception for 3 months following
Surgical management:
Consider if medical management is inappropriate
- Salpingotomy (remove the ectopic)
- Salpingectomy (remove the tube)
A salpingectomy is preferred if the other tube is healthy due to lower future ectopic and retained trophoblast rates.
What is a molar pregnancy?
A benign condition caused by proliferation of placental trophoblastic tissue that remains localised and non-invasive
What is the epidemiology surrounding molar pregnancy?
These are rare; 1-3 in every 1000
What are the risk factors associated with molar pregnancy?
Age
- More common in teenage women (complete only)
- No effect on partial molar pregnancy
Previous molar pregnancy
- Risk increases from 1:600 to 1:100
- If two previous, risk is 15-20:100
Ethnicity:
- More common in east Asian communities
What is the pathophysiology of molar pregnancy?
Molar pregnancies are a result of a genetic error during the fertilisation process of an ovum, which leads to the growth of abnormal tissue within the uterus.
The placental trophoblastic cells behave abnormally, and lead to a collection of fluid filled sacs with the appearance of white grapes.
They are caused by an imbalance of chromosomes:
- Complete: normal sperm cell + empty ovum
- Partial: two sperm cells + normal ovum
What are the characteristics of the different types of molar pregnancy?
Complete:
- Diploid (paternal only)
- Normal sperm + empty ovum
- No foetal tissue
Partial:
- Triploid (maternal and paternal)
- Two sperm cells + normal ovum
- Some foetal tissue but unviable pregnancy
What are the clinical features of a molar pregnancy?
Molar pregnancies usually present as normal pregnancies, and are found at the 10-14 week dating scan.
Some differences in symptoms include:
- Slightly larger than dates uterus, with a soft and boggy feel
- Bleeding
- Hyperemesis
What investigations are performed in a case of molar pregnancy?
Ultrasound confirms the diagnosis:
- An empty uterus with a snow-storm/soap bubbles picture
Other investigations:
- Beta hCG (much higher in molar pregnancy, 100,000 vs 40-60,000IU)
What is the management of molar pregnancy?
Suction curettage:
- Removal of trophoblastic tissue
- Syntometrine given to help with bleeding
Medical evacuation:
- If products do not allow for curettage
Histological confirmation is needed
Strict follow up required
What is the follow-up schedule of a molar pregnancy? How would a persistence of beta hCG be treated?
- Regular hCG measurements for a year (weekly for a month, monthly for 6 months, then bimonthly after that)
- Avoid pregnancy for 6 months after hCG returns to normal
- Use other forms of contraception other than the pill
Persistence of hCG suggests retained products, or malignant change. This is managed with either chemotherapy (actinomycin D) or methotrexate to prevent a choriocarcinoma.
What is the malignant form of molar pregnancy?
Where the trophoblastic tissue becomes invasive to the uterine wall (invasive mole). When it metastasises, it is termed a choriocarcinoma.
These sometimes need to be treated with a hysterectomy.
What is early foetal demise?
Foetal pole is seen but no visible heart beat. It MUST be more than 7mm for this diagnosis. Otherwise, ask to come back in a week.
