Caesarean scar pregnancy (CSP) refers to a pregnancy that is implanted on or in a scar from a prior caesarean birth. CSP occurs in approximately 1 in 2000 pregnancies and accounts for approximately 6 percent of abnormally implanted pregnancies among patients with a prior caesarean birth.
There are two types of caesarean scar pregnancy:
| Type – 1 | Type – 2 |
| On-the-scar – Implantation of the CSP on the well-healed scar of a previous caesarean birth (also termed “endogenous” implantation) | In-the-niche – Implantation of the CSP within the defect or “niche” of an incompletely healed scar (also termed “niche pregnancy,” or “exogenous” implantation). |
The mechanism for implantation of a CSP is unclear; various theories include:
- the endogenous migration of the embryo through either a wedge defect in the lower uterine segment or a microscopic fistula within the scar
- invasion of placental villi into the uterine wall at a point of scar dehiscence
- low oxygen tension of scar tissue attracting implantation of the fertilized oocyte
Some experts believe that CSP is a precursor to, and shares a common histology with, placenta accreta spectrum (PAS) and that they are a continuum of the same disease. Both involve the placenta attaching to or invading the myometrium, almost always in an area of scarring caused by previous uterine surgery.
Risk factors of CSP includes -previous CSP – the risk of recurrent CSP may be more common than previously thought and ranges from 5 to 40 percent. Other factors that may contribute to the risk of CSP in patients with a prior caesarean birth include – Other previous uterine surgery (eg, dilation and curettage [D&C], endometrial ablation, myomectomy), Manual removal of the placenta, In vitro fertilization.
Clinical outcomes of CSP include uterine rupture, enhanced myometrial vascularity and delivery of a neonate followed by caesarean hysterectomy.
As majority of the patients are asymptomatic, diagnosis is mainly via imaging. CSP is diagnosed via USG and in case of doubt MRI can be ordered to rule out co existing PAS. Various management options include – medical management with methotrexate, intra sac injection of kcl or methotrexate, dilatation and curettage and surgery. Management should be individualised depending on the clinical condition of the patient and type of cs pregnancy.
Recently our department had 5 caesarean scar pregnancies in the last 6 months – out of which 3 cases were managed surgically and two medically. Here we are discussing how we have managed a live 10 weeks cs pregnancy with doubt regarding bladder adhesion.
Cesarean Scar Pregnancy With Doubtful Bladder Adhesion
We had a patient – G4P2L2A1/ previous 2 lscs with LMP on 01/06/25 and gestational age – 8 weeks+1 day. She had positive upt test and h/o spotting pv for 1 day. She had USG in UAE which showed CSP hence self-referred to our hospital for further management. Patient was stable while admission. In house USG showed acute retroflexed uterus with live scar ectopic (7.1 x 6.2 cm) of 10 week size. Scar ectopic was bulging outside and abutting abdominal wall and urinary bladder – possibly adherent. We ordered MRI abdomen plus pelvis to rule out bladder adhesion which showed – uterus enlarged and retroflexed with gestational sac with single fetus in the anterior uterine wall embedded at the level of previous caesarean scar. Gestational sac complex appears to extend anteriorly up to the serosal margin with marked thinning of myometrial lining(<1mm). Few foci of serosal interruption noted at the interface with posterior urinary bladder, largest defect -6.5 mm.
We gave her one dose of Methotrexate 80 mg im stat and decided for surgical management via Laparotomy. Intra operative findings include – Uterus enlarged to 6-8 weeks size with products of conception implanted at the site of previous scar with no invasion into the bladder. Bilateral internal iliac artery ligation done. Proceeded with excision of products of conception. Uterine cavity entered – myometrium with serosa approximated. Bilateral salpingectomy done.
Postoperative period was uneventful, and patient discharged on POD-3.
Authored by:
Dr. Rekha D.
MBBS, DNB, DGO
Consultant Gynaecologist
&
Dr. Thithu Lalan. S
MBBS, MS, DNB
Jr. Consultant Gynaecologist
