Miscarriage, Ectopic Flashcards
What is the definition of a miscarriage?
● Spontaneous loss of pregnancy before 24 weeks of gestation (NICE CKS).
What is the pathophysiology and aetiology of miscarriage?
Pathophysiology and Aetiology:
● Chromosomal abnormality (commonest) - typically autosomal trisomies.
○ Can result in failure of development of embryo within gestational sac.
● Hormonal factors:
○ PCOS, hyperprolactinaemia, diabetes, hyper/hypothyroidism
● Thrombophilia / autoimmunity:
○ Antiphospholipid syndrome, factor V Leiden - induces placental thromboses
leading to placental insufficiency.
● Anatomical factors:
○ Bicornuate uterus, cervical insufficiency
● Infection:
○ Toxoplasmosis, syphilis
What are the risk factors for a miscarriage?
● Increased maternal age
● Previous miscarriage
What are the different types of miscarriage?
● Threatened: vaginal bleeding in the first 24 weeks of pregnancy (with viable intrauterine
pregnancy).
● Incomplete: non-viable pregnancy, bleeding begun, products of conception in uterus.
● Complete: all products of conception passed, bleeding has stopped.
● Missed: non-viable pregnancy on ultrasound (without pain / bleeding).
○ Mean gestational sac diameter >25mm with no yolk sac or
○ CRL >7mm with no cardiac activity
● Inevitable: non-viable pregnancy, bleeding begun, cervical os opened, POCs remain in
uterus.
How can a miscarriage present?
● Pelvic pain
● Vaginal bleeding
What are some differentials for for a miscarriage?
gestational
trophoblastic disease, implantation bleeding, ectopic pregnancy, and importantly,
bleeding without an identified cause.
What is first line investigation for a miscarriage?
○ Transvaginal ultrasound scan - to identify location, foetal pole and heartbeat.
How do we manage a threatened miscarriage?
○ Manage conservatively: if no history of previous miscarriage, advise to return if
bleeding persists after 14 days / becomes heavier. If there is a history of previous
miscarriage, offer vaginal progesterone until 16 weeks of pregnancy completed.
○ Advise to take a pregnancy test 3 weeks after bleeding has stopped.
○ If bleeding is ongoing, offer a repeat scan.
How do we manage and incomplete/inevitable miscarriage?
○ First Line - expectant management (appropriate to 13 weeks gestation):
■ Allow 7-14 days for POCs to pass / bleeding to end.
○ Second Line - medical management:
■ mifepristone, followed by misoprostol 48 hours later.
○ Alternative Second Line - surgical management:
■ Vacuum aspiration under local or dilatation and evacuation under GA
○ Plus: pregnancy test 3 weeks post-miscarriage
How do we manage a missed miscarriage?
○ As above, but use misoprostol only for medical management.
What are some contraindications to expectant management?
- Heavy vaginal bleeding / increased risk of bleeding / increased vulnerability to heavy bleeding
(coagulopathy) - Previous traumatic experience in pregnancy
- Evidence of infection
What is the mechanism of mifepristone?
- Antiprogesterone; sensitises myometrium to prostaglandins, induces breakdown of decidua basalis
What is the mechanism of misoprostol?
- Prostaglandin E1 analogue; degrades cervical collagen, stimulates uterine contraction
According to the 1967 Abortion act which four legal grounds give acceptance for a termination of pregnancy?
- Pregnancy before 24 weeks - continuation risks injury to physical / mental health of the
pregnant woman / her children. - Necessary to prevent grave permanent injury to physical / mental health of the pregnant
woman. - Continuation of pregnancy involves risk to the life of the pregnant woman.
- Substantial risk of serious physical / mental disability to the child if it were born.
What is the medical way of abortion?
○ Up to 9+6 weeks - single dose mifepristone, followed by single dose PO / PV
misoprostol 48 hours later
○ 10+0 to 23+6 weeks - single dose mifepristone, followed by serial misoprostol
every 3 hours.
○ Analgesia - NSAIDs, opioids as required.
What is the surgical way of abortion?
○ Up to 13+6 weeks - cervical priming with misoprostol or mifepristone, followed by
vacuum aspiration.
○ 14+0 to 24+0 weeks - cervical priming with mifepristone + misoprostol or osmotic
dilator, followed by dilatation and evacuation.
○ Plus - oral doxycycline to prevent infection.
○ Analgesia - NSAIDs, local anaesthetic, conscious sedation.
Summary of medical and surgical abortion
○ Medical - mifepristone plus misoprostol taken 48 hours later
○ Surgical - misoprostol plus vacuum aspiration / dilatation and evacuation.
Because abortion is a sensitising event, what should be offered?
Anti-D should be offered after 10+0 weeks to women
who are Rhesus negative.
What is the definition of an ectopic pregnancy?
● Any pregnancy that implants outside of the endometrial cavity. 97% are implanted in a
fallopian tube.
Pathophysiology and aetiology of ectopic pregnancy?
● Fertilisation of the oocyte typically takes place in the ampulla of the fallopian tube; the
conceptus must then travel into the endometrial cavity.
○ This occurs due to tubal peristalsis alongside ciliary motion and tubal fluid flow.
○ Any dysfunction in the above due to e.g. tubal surgery, salpingitis, PID can
prevent the conceptus from implanting in the correct place.
● A pregnancy that implants in the fallopian tube will grow and eventually lead to rupture
and catastrophic bleeding.
● Most tubal ectopics implant in the ampulla (widest point).
What are the risk factors for an ectopic pregnancy?
- Previous ectopic pregnancy
- Cu-IUD use (although background risk of pregnancy is obviously much lower).
- Chronic salpingitis (tubal inflammation)
- PID
What is the presentation of ectopic pregnancy?
● Typically presents at 6-8 weeks after LMP; at this point the conceptus has grown to
sufficient size to cause symptoms / signs.
What are the signs of an ectopic pregnancy?
lower abdominal tenderness / adnexal tenderness, cervical motion tenderness.
What are the symptoms of an ectopic pregnancy?
lower abdominal pain, amenorrhea, PV bleeding, urge to defecate, shoulder
pain.
What are the differentials of a ectopic pregnancy?
miscarriage, appendicitis and ovarian torsion.
What should any female of childbearing age presenting with abdominal pain should be offered to exclude ectopic pregnancy>
UPT
Why do the signs and symptoms in ectopic pregnancy occur and what are the indicative of?
Intraperitoneal bleeding
urge to
defecate, shoulder tip pain, cervical motion tenderness.
What are the investigations for an ectopic pregnancy?
- Urine pregnancy test
- Transvaginal ultrasound scan
- Serial serum beta-hCG if no pregnancy found on USS
What is the expectant and medical management for ectopic pregnancy?
● Expectant: must meet certain criteria, and close monitoring required (see text box).
● Medical: oral methotrexate - as long as no surgical criteria are met. Take UPT three
weeks later
What is the surgical management for an ectopic pregnancy?
Surgical: salpingectomy / salpingotomy; indicated if any of the following features are
present:
○ Ruptured ectopic
○ Significant pain
○ Heartbeat on USS
○ >35mm diameter of pregnancy
○ Serum beta-hCG > 5000IU/L
What is the expectant management of an ectopic pregnancy?
- No criteria for surgical intervention can be present
- Measure beta-hCG on days 0, 2, 4, and 7; if drop of more than 15% from previous measurement, repeat
weekly until beta-hCG is less than 20IU/L. If not, refer for further management.
How do we choose the surgery for an ectopic pregnancy?
Salpingectomy (removal of affected tube) is first line unless there are risk factors for infertility; in which case,
salpingotomy (opening of tube for removal of ectopic) is recommended. Salpingotomy is less effective than
salpingectomy. Advise UPT 3 weeks post surgery.
What do we do when there is a pregnancy of unknown location?
- Diagnosed when UPT is positive but no pregnancy can be visualised on ultrasound scanning.
- In this circumstance, the pregnant woman must be closely monitored as there is still a chance of ectopic.
- Diagnosis and management are guided by serial beta-hCG measurements:
- 2 measurements taken 48 hours apart
- If second measurement is >63% greater than first: likely viable intrauterine pregnancy; offer a
scan 7-14 days later - If second measurement is >50% less than first: likely non-viable pregnancy; advise UPT 14
days later - If the second measurement falls between these parameters: further review required for ?ectopic.
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