Cesarean scar pregnancy (CSP) occurs when a pregnancy is implanted in the myometrium at the site of a previous cesarean section scar. The risk factors include previous cesarean section, manual removal of placenta, or other uterine trauma. Transvaginal ultrasound is the primary diagnostic tool, showing an empty uterine cavity with the gestational sac embedded in the cesarean section scar. Treatment depends on gestational age, beta-hCG levels, viability, and involves options like expectant management, medical management with methotrexate, surgical evacuation or resection, or hysterectomy in severe cases. Combination treatments are often most effective in terminating the pregnancy while preserving the uterus.

1. Dr. Alka Pandey
MD, Ph.D.,
Associate Professor, P.M.C.H., Patna

2.  Scar pregnancy is an ectopic pregnancy
implanted in the myometrium at the site of a
previous CS Scar.
 It was first described in 1978 by Larsen and
Soloman.

3. Prevalence
 Prevalence of CSP is increasing and to date
more than 1000 cases have been reported.
 This may be attributed to :
○ Increasing Number of CS
○ Increasing awareness
○ Better diagnostic technique

4. Risk Factors
 May occur after any myometrial trauma -
 Caesarean Section
 Manual Removal of placenta
 Myomectomy
 D & C

5. Pathophysiology
 Endometrial and myometrial disruption of scar are
predisposing factors.
 Invasion by the implanting blastocyst through a
microscopic tract that develops from the trauma of
an earlier CS.
 The risk of scar implantation might be proportional to
the size of the anterior uterine wall defect.
 Caesarean section for a breech presentation in a
previous pregnancy appears to be most frequently at
risk of future CSP.

6. Pathophysiology
 May be secondary to :
○ Systemic diseases – DM (Poor blood flow)
○ Poor tissue quality -
 Inadequate collagen formation
 Post operative wound infection
 Short interval pregnancy
○ Improper closure

7. Diagnosis
 History of amenorrhoea followed by bleeding.
 Positive pregnancy test
 Trans vaginal ultrasound

8. Diagnosis
○ Ultrasound criteria : -
 Empty uterine cavity , closed and empty cervical canal
 Placenta and/or a gestational sac embedded in the scar of a
previous caesarean section
 A triangular/round or oval‐shaped gestational sac that fills the
niche of the scar
 A thin or absent myometrial layer between the gestational sac
and the bladder
 Yolk sac, embryo and cardiac activity may or may not be
present
 Evidence of functional trophoblastic/placental circulation on
colour flow Doppler examination, characterised by high
velocity and low impedance blood flow
 Negative ‘sliding organs’ sign

9. Diagnosis
 Trans abdominal pelvic ultrasound is particularly
useful in later gestation when a trans vaginal scan
may not provide panoramic view.

10. Diagnosis
 TVS 3D ultrasound with Power Doppler
identifies peritrophoblastic vascular flow in
the tissue surrounding the sac and
measurement of the myometrial thickness
is relatively easier.

11. Diagnosis
 MRI is also a useful adjunct.

12. Hysteroscopic Diagnosis

13. Naked eye / laparoscopic picture

14. Classification
 Type-1 or endogenic – where implantation
occurs on the scar and the gestational sac
grows towards the cervico isthmic or uterine
cavity.
 Type-2 or exogenic – CSP occurs when the
gestional sac is deeply embedded in the
scar and the surrounding myometrium and
grows towards the bladder.

15. Types of Scar Ectopic Pregnancy

16. Classification
 The myometrial layer between the
gestational sac and the bladder becomes
very thin and may disappear with bulging of
the gestational sac through the gap as the
pregnancy advances.
 In two – third of the cases the thickness of
the scar may be less than 5 mm.

17. Clinical Presentation
 Asymptomatic – 37%
 Painless vaginal bleeding – 39%
 Generalized abdominal pain – 25%

18. Differential Diagnosis
 Inevitable miscarriage with a low lying sac –
○ In an impending miscarriage the gestational
sac is often irregular and located within the
uterine cavity with absent or minimal colour
Doppler flow.
○ Gentle pressure at the level of the internal os
may displace the gestational sac – sliding
sign.

19. Differential Diagnosis
 Cervical ectopic pregnancy –
○ Present in or close to the cervical canal
with ballooning of the cervix.
○ Good colour flow Doppler and a
negative sliding sign.

20. Risk factors influencing management
choices
Management
 Patient factors
 Symptoms
 Fertility wishes
 Acceptability of prolonged follow up
 Associated lesions
 Surgical risk factors
 Response to initial treatment

21. Management
 Caesarean scar pregnancy (CSP)
 Gestational age
 Human chorionic gonadotropin (hCG) levels
 Size of CSP mass
 Type of CSP
 Myometrial thickness
 Viability
 Facilities
 Interventional radiology
 Surgical expertise/facilities
 Monitoring facilities

22. Management
 No consensus on the preferred mode of treatment.
 All treatment options carry a risk of haemorrhage
and subsequent hysterectomy.
 Treatment should be individualized based on full
pre-treatment evaluation.
 Pregnancy should be ended as soon as possible
after confirming the diagnosis.

23. Management
 Expectant management –
 Used very rarely in selected cases
 Patient must be in stable condition and
thoroughly counseled.
 Close monitoring
 Minimal symptoms
 Compliant
 Type – 1 CSP
 Declining beta HCG
 No fetal cardiac activity

24. Management
 Medical management –
 Candidates –
○ Less than 8 weeks pregnancy
○ Absent fetal cardiac activity
○ Stable
○ Beta HCG <5000 – 12000 IU
○ Myometrial thickness between bladder and
gestation sac >2 mm
 Systemic methotrexate
○ Single dose 1 mg/kg or 50 mg/cm
2
IM at an
interval of 2 or 3 days three or four doses.

25. Management
 Local injection and embolisation –
 Local injection of methotrexate with sac
aspiration
 Local injection of other embryocides

26. Management
 Surgical management
 Dilatation and surgical evacuation
 Hysteroscopic resection
 Vaginal excision and resuturing
 Laparoscopic excision and resuturing
 Open excision and resuturing
 Combined laparoscopic and hysteroscopic
procedure
 Combined laparoscopic and vaginal surgery
 Hysterectomy

27. Management
 Combined or sequential management –
 Uterine artery embolisation/chemoembolisation
followed by dilatation and evacuation/surgical
resection in 24–48 hours
 Methotrexate followed by surgical evacuation or
resection after an interval

28.  Intrauterine Balloon Catheter – can be
used successfully to compress the
gestational sac.
 Catheter is left for 48 hours
 Antibiotics given
 Outer end of the catheter is fastened to
the thigh.

30. Prevention
 Avoid pregnancy 12 to 24 months.
 Surgical repair of uterine scar defects
with single or double layer closure.

31. Summary
 CSP is an uncommon but potentially life-
threatening condition.

 The incidence is rising as CSR is rising.
 Precursor of morbidly adherent placenta.
 Do not confuse CSP with ectopic pregnancy.
 Early diagnosis is important. TVS is the most
effective and preferred diagnostic tool.
 Determine whether heart activity is present.

32. Summary
 If heart activity is documented: Counsel the patient.
 Inform the patient of the risks of pregnancy
continuation.
 If continuation: an additional counseling session:
risks should be explained.
 If termination: a reliable treatment that stops fetal
heart beat without delay.

33. Summary
 Avoid single treatments as they are unlikely to be
effective:
 D&C
 Suction curettage
 Single-dose IM MTX, and UAE
 Removal of Scar ectopic by any of the following
(Hysteroscopy, Laparoscopy, Laparatomy, Vaginally)
and resuturing of the scar

34. Summary
 Consider combination treatments: best results.
direct injection of MTX or Kcl into GS with TVS
guidance.
 In a future pregnancy, an early visit for TVS is
important.

35. Complications
 Placenta previa/accreta
 Uterine rupture
 Massive Haemorrhage : increased
maternal morbidity and mortality.

36. Thank You