Introduction:
Caesarean scar ectopic pregnancy (CSEP) is an unconventional, atypical form of
abnormal implantation which can lead to complications of rupture of uterus and hemorrhage.1-3 The
increasing incidence of ectopic pregnancy in Asia pacific region including India could be due to increasing
number of lower segment caesarean section (LSCS) in the recent past two to three decades.4 It is
necessary to rule out other differentials on ultrasonography which differ from CSEP namely notable C-section
scar tissue or an ongoing miscarriage.5,6 The present case report of CSEP highlights the unusual
case followed by need for early detection and need for routine follow up.
Case Report
A 32 year old female with parity index of gravida 2, para 1, live 1 and past
history of LSCS done 3 years ago, came at 10 weeks of gestation to the obstetrics casualty of Kasturba Hospital
Manipal, with complaints of acute onset of lower abdominal pain which gradually progressed and increased in
intensity over a period of one day. She complained of associated dizziness present throughout the day without
any aggravating or relieving factors. There was no history of abdominal distension or vomiting. Her current
pregnancy had been diagnosed by Urine Pregnancy Test (UPT) at 45 days of amenorrhea. However, she had not
undergone an ultrasound scan following a positive UPT test, and this was her first visit to the hospital in her
current pregnancy. Patient denied any significant medical or surgical history.
Her pulse at initial evaluation was 146 beats/min, respiratory rate at 18 breaths/min, blood pressure measured 88/56 mmHg,
and oxygen saturation was 100% at room air. Patient was immediately resuscitated with intravenous fluids. Examination of
cardiovascular and respiratory system was normal. On abdominal examination, there was no abdominal distension and the abdomen
was tender on palpation. Blood investigations showed hemoglobin of 9 g/dl and β- human chorionic gonadotropin levels of 65563
mIU/ml. Her viral markers were negative. A transabdominal ultrasound was done which revealed significant free fluid in the
abdominal cavity (paracolic gutter and Morrison’s pouch). A regular gestational sac with live fetus of Crown Rump Length (CRL)=
42mm was seen on the scan in the lower part of uterus near uterine isthmus, corresponding to approximately 10 weeks of
gestational age. Due to uncertainty in diagnosis, a diagnostic paracentesis was done which revealed a bloody tap. The
condition of the patient continued to worsen (BP - 70mmHg systolic, 50mmHg diastolic and pulse of 150 beats/min) in a short
period of time, hence she was rushed to the operation theatre for a laparotomy.
Intraoperatively, about 1.8 litres of hemoperitoneum was seen, along with a rent of 5 cms at the site of previous scar on
the anterior uterine wall. A fetus with intact gestation sac was seen protruding through the rent in the abdominal cavity,
right next to the site of the ruptured scar (Fig. 1, 2). Bilateral uterine artery ligation with repair of ruptured scar was
done. The specimen was sent for histopathological examination, and the findings were found to be consistent with products of
conception (Fig.3, 4).
Fig.1:
Fetus with intact gestation sac seen protruding through
the rent in the abdominal cavity |
 |
| Fig.2: Fetus with intact
gestation sac |
 |
 |
| Fig.3: H&E at 400 x showing
villi lined by cytotrophoblast and syncytiotrohphoblast |
Fig.4: H&E at 200x showing
fetal parts with presence of immature cartilage |
Postoperatively patient received 2 pints of packed red blood cells. Her blood test were routinely monitored. Postoperative
recovery period was uneventful hence discharged on tenth day after surgery. Patient was asked to follow up at obstetrics
outpatient department at 6 weeks. When patient had come for follow up, she had resumed her menstrual cycle, and a transvaginal
sonography (TVS) showed intact endometrial cavity.
Discussion
Ectopic pregnancy is quite rare as it is known to occur in 1% of all pregnancies, however the
rate of such pregnancies is on the rise because of the increasing rates of LSCS.7 Approximately 751 cases of
caesarean scar pregnancies have been reported till date8 but very few cases have been reported in Indian scenario.
The mechanism of a caesarean scar pregnancy is believed to involve movement of blastocyst into the myometrium via a
microscopic channel between the endometrial canal and caesarean section scar.9 It can also occur due to
hysterotomy, myomectomy, dilatation and curettage.10 Ash et al, mentioned that a majority of these are
diagnosed in the 1st or early 2nd trimester, with the time gap between previous LSCS and diagnosis of
CSEP ranging between 6 months to about 12 years.11 Our patient was diagnosed 3 years following LSCS, thus making
our patient’s finding consistent with this observation.
Patients with intact ectopic scar pregnancies either have painless bleeding per vagina or lower abdominal pain or
asymptomatic.12,13 Our patient had come with acute lower abdominal pain but absence of vaginal bleeding. However,
the most catastrophic event is hypovolemic shock when uterine dehiscence occurs.14 It is often difficult to
diagnose on ultrasonography because the findings may resemble a cervical ectopic pregnancy due to the lower placement of the
gestational sac with relation to the uterus. It can also be diagnosed by a color flow doppler and TVS, which has a sensitivity
of 86.4% in diagnosis of the condition.15 CSEP is occasionally wrongly diagnosed as incomplete abortion managed
with curettage which can in turn lead to hemorrhage.16 Magnetic resonance imaging, a better diagnostic tool which
precisely detects the exact position of pregnancy but costlier than ultrasonography.17
A caesarean scar pregnancy should be terminated as soon as it is diagnosed as failure to do so can result in a high risk of
obstetric hemorrhage, requiring emergency hysterectomy and thus losing fertility potential.18 The treatment
modality is decided based on factors including gestational age, hemodynamic stability, expertise of the endoscopist, future
pregnancy plans, and practicability of follow-up for serology and imaging.19 Options for the termination of an
uncomplicated ectopic scar pregnancy are curettage, hysteroscopy, systemic methotrexate, laparotomy, hysterotomy and uterine
artery embolization.20
Hysterectomy is the treatment of choice in patients with ruptured uterus with scar rupture extending to cervix,
uncontrollable bleeding or failed conservative management.20 In our patient, laparotomy was decided as patient was
hemodynamically unstable. The uterus was conserved, surgical excision of caesarean scar and scar repair was done in two
layers, since the scar was away from the cervix and the patient wanted to have another pregnancy in the future. Prophylactic
bilateral ligation of uterine arteries was also done to prevent hemorrhage in the near future. Similar cases have been
reported in the past and the same treatment approach was adopted.20,21
Few case series recommended the avoidance of pregnancy 1 or 2 years after scar ectopic pregnancy.21 Our patient
was advised to avoid conception for 2 years. In subsequent pregnancies, recurrent scar implantation may occur.22
So early ultrasound should be performed in order to establish the location of implantation. Few cases have been reported with
successful term pregnancy after a caesarean scar pregnancy.22 However; those pregnancies are at high risk for
uterine rupture (resulting in maternal or fetal death) and placenta accrete,23 thus making it essential to follow
up closely in the subsequent pregnancy. Once the fetal lungs are well developed, early caesarean section is advisable in
pregnancy following a caesarean scar pregnancy, to avoid such complications.24
Conclusion
The occurrence of a CSEP in a female with past history of LSCS is a rare
phenomenon. However, this can result in life threatening uterine rupture as a complication. The doctor should
bear in mind that such pregnancies may occur especially in women with low lying gestational sac in previous
scarred uterus and should be diagnosed and managed at the earliest in order to prevent such a complication.
References
- Timor-Tritsch IE, Monteagudo A, Santos R, et al. The diagnosis, treatment, and follow-up of
caesarean scar pregnancy.
Am J Obstet Gynecol. 2012;207(1):44.e1-13.
- Fylstra DL. Ectopic pregnancy within a caesarean scar: a review. Obstet Gynecol Surv 2002;57:537–43.
- Kung FT, Huang TL, Chen CW, Cheng YF. Image in reproductive medicine.
Caesarean scar ectopic pregnancy.
Fertil Steril. 2006;85(5):1508-9.
- Yin L, Tao X, Zhu YC, Yu XL, Zou YH, Yang HX. Caesarean scar pregnancy analysis of 42 cases.
Chin J Obstet Gynecol. 2009;44(08):566–69.
- Weimin W, Wenqing L. Effect of early pregnancy on a previous lower segment
caesarean section scar.
Int J Gynaecol Obstet. 2002;77:201-7.
- Einenkel J, Stumpp P, Kösling S, et al. A misdiagnosed case of caesarean scar pregnancy.
Arch Gynecol Obstet. 2005;271:178-81.
- Seow KM, Huang LW, Lin YH, et al. Caesarean scar pregnancy: issues in management.
Ultrasound Obstet Gynecol. 2004;23(3):247-53.
- Timor-Tritsch IE, Monteagudo A. Unforeseen consequences of the increasing rate of
caesarean deliveries: early placenta accreta and caesarean section scar pregnancy; a review.
Am J Obstet Gynecol. 2012;207(1):14-29.
- Jurkovic D, Hillaby K, Woelfer B, et al. First-trimester diagnosis and management of pregnancies implanted into the lower uterine caesarean section scar.
Ultrasound Obstet Gynecol. 2003;21(3):220-7.
- Patel MA. Scar Ectopic Pregnancy. J Obstet Gynecol India. 2015;65(6):372–5.
- Ash A, Smith A, Maxwell D. Caesarean scar pregnancy. BJOG. 2007;114(3):253-63.
- Rosen T. Placenta accreta and caesarean scar pregnancy: overlooked costs of the rising caesarean section rate.
Clin Perinatol. 2008;35(3):519-29.
- Rotas MA, Haberman S, Levgur M. Caesarean scar ectopic pregnancies: etiology, diagnosis and management.
Obstet Gynecol. 2006;107(6):1373-81.
- Yu XL, Zhang N, Zuo WL, et al. Caesarean scar pregnancy: an analysis of 100 cases.
Zhonghua Yi Xue Za Zhi. 2011;91(45):3186-9.
- Jain S, Chaudhary S, Jain N, Ranjan R. Ruptured caesarean scar ectopic pregnancy: a rare case report.
Int J Reprod Contracept Obstet Gynecol. 2015;4(6):2111-2.
- Fylstra DL, Pound-Chang T, Miller MG, Cooper A, Miller KM. Ectopic pregnancy within a caesarean delivery scar: a case report.
Am J Obstet Gynecol. 2002;187(2):302-4.
- Osborn DA, Williams TR, Craig BM. Caesarean scar pregnancy: sonographic and magnetic resonance imaging findings, complications, and treatment.
J Ultrasound Med. 2012;31(9):1449-56.
- Maymon R, Halperin R, Mendlovic S, et al. Ectopic pregnancies in Caesarean section scars: the 8 year experience of one medical centre.
Hum Reprod. 2004;19(2):278-84.
- Elizabeth LA, Moussavian B, Horrow MM. Caesarean Delivery Scar Ectopic Pregnancy.
Ultrasound Quarterly. 2010;26(2):107-9.
- Deb S, Clewes J, Hewer C, et al. The management of
Caesarean scar ectopic pregnancy following treatment with methotrexate--a clinical challenge.
Ultrasound Obstet Gynecol. 2007;30(6):889-92.
- Hasegawa J, Ichizuka K, Matsuoka R, et al. Limitations of conservative treatment for repeat
Caesarean scar pregnancy.
Ultrasound Obstet Gynecol. 2005;25(3):310-1.
- Ben Nagi J, Helmy S, Ofili-Yebovi D, Yazbek J, Sawyer E, Jurkovic D. Reproductive outcomes of women with a previous history of Caesarean scar ectopic pregnancies.
Hum Reprod. 2007;22(7):2012-5.
- Ben Nagi J, Ofili-Yebovi D, Marsh M, et al. First trimester caesarean scar pregnancy evolving into placenta previa/accrete at term.
J Ultrasound Med. 2005;24:1569–73.
- Koroglu M, Kayhan A, Soylu FN, et al. MR imaging of ectopic pregnancy with an emphasis on unusual implantation sites.
Jpn J Radiol. 2013;31(2):75-80.
|
