Caesarean Scar Pregnancy:                               Menace of increasing caesarean section rate

OBG-Speculum:    2024                       ISSN no.

Vol -2, Issue -1  

Dr Vibha Rani Pipal

A pregnancy that is implanted on or in a scar from a previous caesarean delivery is known as a caesarean scar pregnancy (CSP). It is identified based on transvaginal ultrasound (TVUS) results from the first or early second trimester of a pregnancy implanted on or in a previous hysterotomy scar or niche. Histologic results consistent with placenta accreta spectrum (PAS) disorder, which is identified later in pregnancy, are confirmed during surgery. As the rate of caesarean sections rises, so does the incidence of both disorders. This can cause significant morbidity and mortality in both the mother and the foetus if left undiagnosed or treated insufficiently.

Multiple classifications are suggested for caesarean scar pregnancy.

There are two primary categories based on residual myometrial thickness and the location of CSP: Type 1 (on the scar): The CSP is implanted on the healed scar from an earlier caesarean delivery or endogenous implantation. Type 2 (in-the-niche) refers to the exogenous implantation of the CSP, also known as niche pregnancy, within the defect or "niche" of an incompletely healed scar [1].

Depending on which way the CSP develops, there are three other classifications that are proposed: (1) CSP in which the majority of the GS protrudes into the uterine cavity; (2) CSP in which the majority of the GS is embedded in the myometrium but does not cross the serosal contour; and (3) CSP in which the GS is partially located outside the cervix or uterus's outer contour [2].

Based on the thickness and gestational sac width, a new classification system was developed to categorize ectopic pregnancies that resulted from caesarean scarring into five categories. Based on expert opinion, a recommended surgical treatment method was developed for each type. Using this classification system, the total success percentage of the suggested first-line surgical treatment was 97.5%. Within three weeks following surgery, 85% of patients had a negative serum β-hCG level, and within eight weeks, 95.2% of patients were able to resume their menstrual periods. Figure-1[3].

Surgical and non-invasive medical techniques are available for management. Methotrexate (MTX), uterine artery embolization (UAE), high-intensity focused ultrasound therapy (HIFU), and direct local embryocidal injection into the sac with concurrent sac aspiration are nonsurgical possibilities. Laparoscopy, laparotomy, hysteroscopy and curettage, and gestational sac suction evacuation are among the surgical therapy options available. Most instances are handled in a hybrid fashion [4].

This iatrogenic condition can be prevented by promoting the indicated caesarean deliveries and successful management requires an early diagnosis and a multidisciplinary team approach including the interventional radiologists. 

References:

1. Kaelin Agten A, Cali G, Monteagudo A, Oviedo J, Ramos J, Timor-Tritsch I. The clinical outcome of cesarean scar pregnancies implanted "on the scar" versus "in the niche". Am J Obstet Gynecol. 2017 May;216(5):510.e1-510.e6. doi: 10.1016/j.ajog.2017.01.019. Epub 2017 Jan 20. PMID: 28115056.  DOI: 10.1016/j.ajog.2017.01.019

2. Jordans IPM, Verberkt C, De Leeuw RA, Bilardo CM, Van Den Bosch T, Bourne T, Brölmann HAM, Dueholm M, Hehenkamp WJK, Jastrow N, Jurkovic D, Kaelin Agten A, Mashiach R, Naji O, Pajkrt E, Timmerman D, Vikhareva O, Van Der Voet LF, Huirne JAF. Definition and sonographic reporting system for Cesarean scar pregnancy in early gestation: modified Delphi method. Ultrasound Obstet Gynecol. 2022 Apr;59(4):437-449. doi: 10.1002/uog.24815. PMID: 34779085; PMCID: PMC9322566. DOI: 10.1002/uog.24815

3.     Ban Y, Shen J, Wang X, Zhang T, Lu X, Qu W, Hao Y, Mao Z, Li S, Tao G, Wang F, Zhao Y, Zhang X, Zhang Y, Zhang G, Cui B. Cesarean Scar Ectopic Pregnancy Clinical Classification System With Recommended Surgical Strategy. Obstet Gynecol. 2023 May 1;141(5):927-936. doi: 10.1097/AOG.0000000000005113. Epub 2023 Apr 5. PMID: 37023450; PMCID: PMC10108840.  doi: 10.1097/AOG.0000000000005113

4. Hameed MSS, Wright A, Chern BSM. Cesarean Scar Pregnancy: Current Understanding and Treatment Including Role of Minimally Invasive Surgical Techniques. Gynecol Minim Invasive Ther. 2023 Apr 19;12(2):64-71. doi: 10.4103/gmit.gmit_116_22. PMID: 37416110; PMCID: PMC10321345. doi: 10.4103/gmit.gmit_116_22