Part 1
Cornerstones of diagnosis are:
 history and examination
 hCG
 transvaginal ultrasound
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Glycoprotein with  and  sub-units linked by
disulfide bond ( same in all glycoprotein
hormones inc. FSH, LH, TSH;  subunit confers
unique biological activity and specificity in
radioimmunoassays)
Secreted by syncytiotrophoblast of the chorion
Prevents degradation of the corpus luteum
(Corpus luteum produces progesterone and some
oestrogen which causes the endometrial glands to
prepare for implantation of the blastocyst)
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Initially rises exponentially and after 6 weeks
(>6000-10000 mIU/mL) more slowly
“Doubling time” useful in first 6 weeks
66% considered to be minimal rise in 48 hours
for normal intrauterine pregnancy (85%
confidence interval ie. 15% normal pregnancies
have less than this rise & 15% ectopics have
this rise)
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Plateauing hCG suggests ectopic
Falling hCG - rate important
Half life less than 1.4 days – rarely ectopic
Half life more than 7 days – most predictive of
ectopic
Single level – useful only as indication for
expected ultrasound findings (depending on
quality of ultrasound service)
3-100 x higher than normal pregnancy levels in
gestational trophoblastic disease
25-29 days (from LNMP)
Intradecidual sac sign (small
gestational sac in decidua)
(only 50% early pregnancies)
Double sac sign (decidua and
membranes)
34 days (earliest)
Usual 37-38 days
Gestational sac (hCG 1000-
36 days (earliest)
Usual 42 days
Yolk sac
43 days (earliest)
Usual 45 days
Embryo
43 days (earliest)
Usual 45 days
Embryonic cardiac activity
1500 = discriminatory zone. 6000
on T/A scan)
(CRL >5mm, hCG >25000)
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Gestational sac >13mm without yolk sac or
>17mm without embryo means a non-viable
pregnancy
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Not very useful
>25ng/mL – likely viable intra-uterine
pregnancy
<5 ng/mL – abnormal pregnancy but don’t
know if intra- or extrauterine
Most between 10 and 20 with early pregnancy
bleeding/pain
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Differential diagnosis:
Miscarriage/abortion (intra-uterine pregnancy)
Ectopic pregnancy
Other – cervical polyps, vaginitis, trauma,
foreign body, cervical carcinoma, gestational
trophoblastic disease (molar pregnancy)
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Spontaneous:
20-30% of all known pregnancies (80% in 1st
trimester). If pregnancy failure has occurred,
usually before 8 weeks
Threatened:
30-40% all pregnancies
Small PV loss
Uterine size =dates
Os closed
Fetal heart seen or too early to be seen
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Missed:
Uterine size < dates
Os closed
May not have bleeding at first
Fetal pole with no fetal heart
Inevitable:
Heavy PV loss, usually clots
Cervix open
Initially no products passed
Incomplete:
< 6 weeks usually fetus and placental tissue passed
together vs >6 weeks
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Blighted ovum (fertilised but anembryonic)
Chromosomal anomalies
Embryonic anomalies
Uterine anomalies
IUD
Teratogens (any agent which affects the developing embryo)
Mutagens (any agent which changes the DNA of germ cells)
Maternal disease
Placental abnormalities
Trauma
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History and examination
hCG +/- ultrasound
(ALWAYS DO A PREGNANCY TEST FOR
BLEEDING FEMALE IN REPRODUCTIVE
AGE GROUP)
ALWAYS THINK ABOUT ECTOPIC
ALWAYS CHECK BLOOD GROUP
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Threatened – observe
Missed – suction curettage
Inevitable or incomplete – expectant if stable or
suction curettage or misoprostil
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Next week…