Module 6.1 : Classification of Abortions Flashcards
abortion - definition
- termination of pregnancy prior to 20 weeks, either spontaneous or induced
- rate of pregnancy loss is 25%
- over 40 years old increases to 50%
Threatened abortion
- bleeding with a viable intrauterine pregnancy
- heart beat is seen
- usually result of implantation
embryonic demise
- an embryo is present but no heart beat is detected
or - no fetus is visualized within the retained membranes, inly gestational sac visualized
spontaneous abortion with no retained parts
- uterus is normal or non gravid
factors causing SA - maternal
- malformations of uterus \+ synechiae (scars) \+ fibroids (take up volume) \+ septet uterus - toxic agents \+ tabacco \+ alcohol - systemic infection - hormonal failure - poor trophoblastic reaction - advanced maternal
factors causing SA - fetal
- malformations
- genetic (50-70%)
factors causing SA - maternal and fetal
- RH incompatibility
+ RH is the Rhesus factor an antigen on the red blood cells
+ mother is Rh- and the fetus (2nd pregnancy) is Rh+
clinical signs of abortion
- vaginal bleeding \+ spotting \+ light \+ heavy - cramping - dilated cervix - uterine contractions * heavy bleeding with painful cramps is 3x more likely to miscarry
vaginal bleeding
- 50% will lose pregnancy
- heavy bleeding and pain pose greater risk
- 17% that don’t miscarry will have complications with the pregnancy such as PROM (premature rupture of membranes) and preterm labor
- not all bleeding comes from pregnancy, can arise from cervix, vagina or uterus
treatment
- do nothing
+ let nature take its course - have a D & C
+ dilation and curettage
+ dilate the cervix and scrape the uterine cavity
+ curettage means the cleansing of diseased surface
changes in uterine size
- at 6 weeks the gestational sac occupies less than 1/2 of total uterine cavity
- by 8 weeks the gestational sac occupies 1/2 of the uterine cavity
- by 10 weeks the sac occupies the entire cavity
MSD and yolk sac visualization
- EV = see yolk sac when MSD 8mm
- TA = see yolk sac when MSD 20mm
viable pregnancies
- a 6 week normal intrauterine pregnancy ultrasound results in favourable outcome =s
- a 12 6/7 week normal intrauterine pregnancy ultrasound
+ reduces risk of loss to 1-2%
+ not because ultrasound but demonstrates of a confirmation of normal pregnancy by US
classifications of abortions
- threatened abortion
- anembryonic/blighted ovum
- embryonic demise/missed abortion
- inevitable abortion/in progress
- incomplete abortion
- complete abortion
- habitual abortions
- specific abortions
threatened abortion
- vaginal bleeding
- ultrasound shows normal pregnancy
- cervix is closed
- may have cramping
- possibly implantation bleed
- could be a resolving coexisting twin or vanishing twin
anembryonic
- aka blighted ovum
- gestational sac develops
- no embryo
- usually no yolk sac
- bleeding with ‘’+” pregnancy test
sonographic appearance of anembryonic
- uterus is small for dates
- gestational sac without a fetus
- MSD greater than 20mm and no embryo seen
- F/U (follow up) in 10 days
+ to see if anything changed, give pregnancy benefit of the doubt - may need D & C
embryonic demise
- aka missed abortion
- fetus dies but remains in uterus
- bleeding
- small for dates uterus
- 5mm or greater embryo without fetal heart
- occurs between 10 and 14 weeks
+ embryo died earlier but the patient hasn’t had any symptoms of loosing the pregnancy yet
embryonic demise - sonographic appearance
- no FH
- macerated uterus
+ fetal tissue breaking down - irregular walls
- spalding sign
+ brain atrophy and skull bones collapsing - M mode only definitive way to show demise
+ color doppler over fetal heart to confirm demise
Inevitable abortion
- in progress
- patient presenting with active bleeding and cramping
- clinically patient has an open cervix
inevitable abortion - sonographic appearance
- clot in endometrium
- sac low in uterus
- may still see a FH but placenta detached
differential diagnosis - inevitable abortion
- cervical ectopic pregnancy
+ negative dynamic EV
- dynamic EV putting pressure to see if structures move + if structures move - if structures do not move
+ dynamic EV scan will help differentiate from inevitable abortion
incomplete abortion
- some parts of conception have passed but some still remain
- ask patient if they haves passed clots or tissue
incomplete abortion - sonographic appearance
- enlarged uterus
- poorly defined gestational sac
- may see an echogenic mass like structure
complete abortion
- all products of conception have passed
- bleeding and cramping have ceased
complete abortion - sonographic appearance
- empty uterus
- enlarged uterus
- may see some blood between the endometrium lining
- deciding if need a D&C
habitual abortions
- 3 or more consecutive abortions
- may be due to
+ luteal failure
+ retroverted uterus
+ DES exposure - T shaped uterus
+ unicornuate uterus
+ chromosomal abnormalities
septic abortion
- infected products of conception
- after a spontaneous or therapeutic abortion
- pain, FEVER, bleeding, and discharge
septic abortion - sonographic appearance
- retained products
- thick endometrium
- if their are gas producing organisms air shadow may be visualized
Therapeutic abortions
- selective abortions are performed for malformations
- in Alberta therapeutic abortions are performed
+ up to 20 weeks for personal reasons or fetal abnormalities
+ from 20w 1d to 22w 6d for any fetal abnormalities
+ from 23weeks to term only if lethal fetal abnormality is diagnosed
role of sonography for TA
- dating of pregnancy prior to termination when a size discrepancy is suspected
- diagnosis of masses or malformations that might hinder procedure
- localizations of IUCD
- guidance in difficult cases
- post TA
+ diagnosis of complications from termination
methods of inducing abortion
- less than 14 weeks = D&C
- greater than 14 weeks = induction of labor using prostaglandin or hypertonic saline urea