RESUMEN
Caesarean section is associated with an increased risk of abnormal placental implantation and adverse pregnancy outcomes in subsequent pregnancies. Besides the placenta accrete spectrum, only a few of the previous studies focused on other placental development alterations in the scarred uterus. We assessed placental development deviations in the uterus with a Caesarean section scar by evaluating placental volume (PV) and vascular flow indexes. From 1 January 2021 until 31 March 2022, placental volumes and vascularization indexes (VI, FI, VFI) were prospectively measured by 3D power Doppler and VOCAL techniques in 221 patients attending the first trimester screening program. We also calculated the placental quotient to standardize PV to the gestational age. No statistically significant differences in the values of placental volume, placental quotient and placental vascularization indexes were detected between women with previous Caesarean section delivery or women with vaginal delivery. FI was significantly lower in nulliparous in the first trimester. The results of our study suggest that 3D placental evaluation was not able to detect placental development alteration in the uterus with a Caesarean section scar. Future research needs to verify whether 3D power Doppler and Vocal techniques can provide more information if used in an earlier gestational age.
RESUMEN
OBJECTIVE: To compile existing knowledge on the level of cervical regeneration (detected by ultrasound) after loop electrosurgical excision procedure (LEEP) and to suggest research protocol for further studies. METHODS: We conducted a literature search of Medline, Web of Science, Scopus, and Cochrane databases using the keywords "cervix" and "regeneration" without year restrictions. Our eligibility criteria included studies that analysed cervical volume and length regeneration using ultrasound. A literature review was conducted following PRISMA guidelines and registered in PROSPERO (reg. no. CRD42021264062). Information about the studies was extracted from each analysed study on an Excel datasheet and the average regeneration with standard deviation was calculated. All included studies' possible biases were assessed by the National Institutes of Health's (NIH) quality assessment tool. RESULTS: The literature search identified 802 papers and four trials (n = 309) that met our criteria. They investigated cervical length and volume regeneration after LEEP using ultrasound, concluding that there is a profound regeneration deficit. Average cervical length regeneration after 6 months was 83.4% (±10.8%) and volume regeneration was 87.4% (±6.1%). All analysed studies had their biases; therefore, based on the conducted studies' protocols, we present a CeVaLEP research protocol to guide high-quality studies. CONCLUSION: After LEEP, there is a cervical regeneration deficit. There is a lack of high-quality studies that assess cervical volume regeneration and its relation to obstetrical outcomes. There is a gap in the field and more research is needed to define the prenatal risks related to cervical regeneration.
