abortions

1. Spontaneous abortion
Dr.Renu Singh

2. Definition
• Clinically recognised pregnancy loss before
20th week of gestation
• Expulsion or extraction of an embryo or fetus
weighing 500gm or less(WHO)
• Synonymous with miscarriage
• Latin :aboriri: to miscarry

3. Incidence
• MC early pregnancy complication
• Frequency decreases with increasing
gestational age
• Incidence:8-20%(clinically recognised
pregnancies)
• Women who had a child: 5% incidence of
miscarriage
• 80% spontaneous abortion :< 12 wks

4. Risk factors
• Advanced maternal age
• Previous spontaneous abortion
• Medications & substances (smoking)
• Mechanisms responsible for abortion: not
apparent
• Death of fetus precedes spont. expulsion,
finding cause involves ascertaining the cause
of fetal death

5. Maternal age
• Most important risk factor in healthy women
• 30yrs:9-17%
• 35yrs:20%
• 40yrs:40%
• 45yrs: 80%

6. Previous spontaneous abortion
• Previous successful pregnancy: 5% risk
• 1 miscarriage: 20%
• 2 consecutive miscarriages:28%
• ≥3 consecutive miscarriages:43%

7. Medications or substances
• Heavy smoking(>10 cigarettes/day) :
vasoconstrictive & antimetabolic effects of
tobacco smoke
• Moderate to high alcohol consumption(>3
drinks/week)
• NSAIDS use(acetaminophen) :abnormal
implantation & pregnancy failure due to
antiprostaglandin effect

8. Other factors
• Low plasma folate levels(≤2.19ng/ml): no
specific evidence to support
• Extremes of maternal weight: prepregnancy
BMI<18.5 OR >25kg/m2
• Maternal fever:100°F(37.8°C), no evidence to
support

9. Etiology
• Fetal
• Maternal
• unexplained

10. Etiology
• Foetal factors
– Chromosomal abnormalities(50% ),
• aneuplodies ,monosomy X,Triploidy
• Trisomy 16 : mc autosomal trisomy,lethal
• Abnormalities arise de novo
– Congenital anomalies
– Trauma: invasive prenatal diagnostic procedures

11. Aetiology :Maternal factors
– Maternal endocrinopathies: hypothyroidism,
insulin dependant diabetes
– Congenital or acquired uterine abnormalities:
interfere with implantation & growth
– Maternal diseases: acute maternal infection
(listeria, toxo, parvo B19,rubella,CMV) :
inconclusive
– Radiation in therapeutic doses
– Hypercoagulable state(thrombophillias) : RPL

12. Clinical presentation
• Vaginal bleeding
– Scant brown spotting to heavy vaginal bleeding
– Amount /pattern does not predict outcome
– May be accompanied by passage of fetal tissue
• Pelvic pain
– Crampy /dull in character
– Constant/intermittent
• Incidental finding on pelvic ultrasound in
asymptomatic patient

13. Diagnostic evaluation
• History
– Period of amenorrhea ,LMP/USG
• Physical examination: Complete pelvic
examination:
– P/S,:source, amount of bleeding, dilated cervix,
POC visible at Os/in vagina
– P/V: uterine size(consistent with GA)
• Pelvic ultrasound

14. Pelvic ultrasound
• Most useful test in diagnostic evaluation of
women with suspected spontaneous abortion
• Foetal cardiac activity: most important (5.5-
6wks)
• Foetal heart rate
• Size & contour of G.sac
• Presence of yolk sac
• Best evaluated ,transvaginal approach(TVS)

15. Pelvic USG: criteria for spontaneous
abortion
• Gestational sac ≥ 25mm in mean diameter
that does not contain a yolk sac or embryo
• An embryo with CRL ≥7 mm with no cardiac
activity
If the GS or embryo is smaller than these dimensions:
repeat pelvic USG in 1-2 weeks

16. Differential diagnosis
• Physiologic: placental sign
• Ectopic pregnancy
• Gestational trophoblastic disease
• Cervical/vaginal/uterine pathology
• Physical examination
• Transvaginal sonography(TVS)
• Serial quantitative ßhCG

17. Lab evaluation
• Human chorionic gonadotropin: serial,
quantitative, useful in inconclusive USG
findings
• ABO ,Rh: need for 50/300µg anti D
• Haemoglobin/hematocrit
• Serum progesterone<5ng/ml(nonviable
pregnancy)

18. Post diagnostic classification
• Based upon the location of POC
• Degree of cervical dilatation(pelvic exam)
• Pelvic ultrasound
• Categorization impacts clinical management
– Threatened
– Inevitable
– Incomplete/complete
– Missed

19. Threatened abortion
• Vaginal bleeding has occurred
• The cervical os is closed
• Diagnostic criteria for spontaneous abortion
has not met
• Managed expectantly: until symptoms resolve
or progresses

20. Threatened abortion: m/m
• Expectant
• Progestin treatment: most promising, efficacy
not established
• Bed rest: randomised trials have refuted the
role
• Avoid vigorous activity
• Avoid heavy lifting
• Avoid sexual intercourse

21. Threatened abortion :m/m
• Counsel about risk of miscarriage
• Return to hospital in case of additional vaginal
bleeding, pelvic cramping or passage of tissue from
vagina
• Repeat pelvic USG until a viable pregnancy is
confirmed or excluded
• Viable pregnancy, resolved symptoms: prenatal care
• If symptoms continue: monitor for progression to
inevitable, incomplete, or complete abortion

22. Inevitable abortion
• Vaginal bleeding, typically accompanied by
crampy pelvic pain
• Dilated cervix( internal os)
• Products of conception felt or visualised
through the internal os

23. Incomplete abortion
• Vaginal bleeding and/or pain present
• Cervix is dilated
• Products of conception partially expelled out
• Uterine size less than period of amenorrhea

24. Missed abortion
• Non viable intrauterine pregnancy
• Cervical os is closed
• POC not expelled
• May notice that symptoms associated with
early pregnancy have abated

26. Management
• Complete evacuation of uterine contents(POC)
• Surgical methods: suction evacuation/suction
curettage/dilation & evacuation
• Medical methods: Misoprostol,mifepristone
• Expectant
• All have similar efficacy

27. Surgical evacuation
• Performed under IV sedation & paracervical
block
• Prophylactic antibiotics
• Operating room/procedure room
• Potential complications
• Anaesthesia related,
• uterine perforation, cervical trauma,
• infection, intrauterine adhesions

28. Medical methods
• Misoprostol: drug of choice
• Efficacy depends on dose & route of
administration
• 400mcg vaginally every 4 hours for 4 doses
• Expulsion rate : 50-70%
• Low cost, low incidence of side effects, stable
at room temperature, readily available, timing
of use can be controlled by patient

29. Misoprostol
• WHO consensus report on misoprostol
regimen
– Missed abortion: 800mcg vaginally,or 600 mcg
sublingually
– Incomplete abortion: 600mcg orally
• Expulsion rate: 70-90%

30. Choosing the method
• Surgical evacuation : heavy bleeding,
intrauterine sepsis, medical co morbidities,
misoprostol is contraindicated
– Shorter time to completion of treatment
– Lowers risk of unplanned admissions
– Lower need for subsequent treatment

31. Expectant m/m
• Stable vital signs
• No evidence of infection
• Offered after proper counseling
• If unsuccessful after 4 wks ,surgical evacuation
is needed

32. Complete abortion
• POC expelled completely from uterus &
cervix
• Cervical os is closed
• Uterus small in size (GA)
• Resolved or minimal vaginal bleeding & pain
• Aim of t/t: ensure that bleeding is not
excessive & all POC have expelled
• Theoretically does not need treatment

33. Abortion : complications
• Hemorrhage
• Uterine perforation
• Retained products of conception
• Endometritis
• Septic abortion: abortion accompanying
intrauterine infection

35. Summary
• Clinically recognised pregnany losses <20 wks
gestation
• Most common complication of early
pregnancy
• Advanced maternal age, previous
spontaneous abortion, maternal smoking: risk
factors
• Mostly due to fetal structural/chromosomal
abnormalities

36. Summary
• Present with menstrual delay, vaginal
bleeding& pelvic pain
• D/D: uterine or other genital tract bleeding in
viable pregnancy, ectopic,& GTD
• Pelvic examination & pelvic ultrasound: key
elements for diagnosis
• Spontaneous abortion diagnosed based on
USG criteria
• Categorised as threatened/incomplete/missed

37. Summary
• Preconceptual & prenatal counseling & care
regarding modifiable aetiologies ,risk factors
are most imp intervention
• Normal menstrual cycle resumes in 4-6 weeks
• hCG returns to normal 2-4wks

38. Prevention of spont.abortion
• Preconception & prenatal counseling
• Routine screening & optimal disease
control(diabetes, thyroid, thrombophilia)
• Correction of uterine structural
anomalies(septum, submucosal myoma,
intrauterine adhesions) prior to pregnancy
• Avoiding exposure to teratogen or infections
• Modifiable risk factors