Prospective Evaluation of the Ultrasound Signs Proposed for the Description of Uterine Niche in Nonpregnant Women

Reproductive surgery remains an essential element of reproductive medicine

Background

Reproductive surgery has long been neglected and is perceived to be simple surgery that can be undertaken by all gynaecologists. However, given the ever-expanding knowledge in the field, reproductive surgery now comprises surgical interventions on female reproductive organs that need to be carefully planned and executed with consideration given to the individuals symptoms, function of the organ and fertility concerns.

Objectives

To discuss the different perspectives of reproductive surgeons and other gynaecological surgeons, e.g., gynaecological oncologists, and advanced minimally invasive surgeons, regarding diagnosis and management of pelvic pathology that affects reproductive potential. Furthermore, to highlight the gaps in knowledge and numerous controversies surrounding reproductive surgery, while summarising the current opinion on management.

Materials and Methods

Narrative review based on literature and the cumulative experience of the authors.

Main outcome measures

The paper does not address specific research questions.

Conclusions

Reproductive surgery encompasses all reproductive organs with the aim of alleviating symptoms whilst restoring and preserving function with careful consideration given to alternatives such as expectant management, medical treatments, and assisted reproductive techniques. It necessitates utmost technical expertise and sufficient knowledge of the female genital anatomy and physiology, together with a thorough understanding of and respect to of ovarian reserve, tubal function, and integrity of the uterine anatomy, as well as an up-to-date knowledge of alternatives, mainly assisted reproductive technology.

What is new?

A holistic approach to infertile women is only possible by focusing on the field of reproductive medicine and surgery, which is unattainable while practicing in multiple fields.

Abnormal Uterine Bleeding in Reproductive Age Women: Role of Imaging in the Diagnosis and Management

Abnormal uterine bleeding (AUB) is defined by the International Federation of Gynecology and Obstetrics as bleeding from the uterine corpus that is abnormal in regularity, volume, frequency, or duration and occurs in the absence of pregnancy. AUB is a common condition that affects about a third of women in their lifetime. Abnormal bleeding in duration, quantity, or timing consists of 2 categories, predictable cyclical heavy menstrual bleeding (HMB) and irregular non-cyclical intermenstrual bleeding (IMB). The most common causes of HMB include fibroids and adenomyosis and IMB is commonly caused by ovulatory dysfunction such as in polycystic ovaries, endometrial polyp, or an IUD. A pelvic ultrasound is the initial and often only imaging modality needed in the imaging evaluation of abnormal uterine bleeding and can accurately identify the common causes of abnormal uterine bleeding in the reproductive age group.

Effect of cervical changes on the cesarean scar area and niche formation after preterm and term cesarean sections

OBJECTIVE

The purpose of this study is to assess the scar area and niche formation after cesarean section in women who had preterm or term deliveries and underwent cesarean section at various stages of labor.

METHOD

This prospective cohort study consists of cases who underwent the first cesarean section for different obstetric reasons. The patients were divided into four groups regarding gestational age and cervical dilatation. After a cesarean section, all patients were called for vaginal ultrasonography control at 12 weeks. The location of the scar and the presence of a niche were evaluated. The residual (RMT), proximal, and distal myometrial thicknesses were evaluated where the scar and niche were located.

RESULTS

A total of 87 cases were included in the study. There was no difference in the prevalence of niche between the groups (p > 0.05). RMT and proximal and distal myometrial thickness were not different between the 37 ≥ week and 37 < week groups, while RMT and proximal and distal myometrial thickness were significantly lower in women with active labor (p =0.001, p= 0.006, p =0.016). The location of the scar was the isthmus at 37 weeks and above (p= 0.002), it was in the cervical canal in the group below 37 weeks (p= 0.017).

CONCLUSION

The gestational week and cervical changes did not affect the prevalence of the niche. In cases of active labor and preterm deliveries, the CS scar defect was located in the cervical canal; however, in cases of term deliveries, it was located in the isthmic area.

Aetiology, risk factors and preventive strategies for niche development: A review

The increase in caesarean sections (CS) has resulted in an increase in women with a uterine niche. The exact aetiology of niche development has yet to be elucidated but is likely multifactorial. This study aimed to give a systematic overview of the available literature on histopathological features, risk factors and results of preventive strategies on niche development to gain more insight into the underlying mechanisms. Based on current published data histopathological findings associated with niche development were necrosis, fibrosis, inflammation, adenomyosis and insufficient approximation. Patient-related risk factors included multiple CS, BMI and smoking. Labour-related factors were CS before onset of labour, extended cervical dilatation, premature rupture of membranes and presenting part of the fetus at CS below the pelvic inlet. Preventive strategies should focus on the optimal level of incision, training of surgeons and full-thickness closure of the myometrium (single or double-layer) using non-locking sutures. Conflicting data exist concerning the effect of endometrial inclusion. Future studies without heterogeneity in population, using standardized performance of the CS after proper training and using standardized niche evaluation with a relevant core outcome set are required to allow meta-analyses and to develop evidence-based preventive strategies. These studies are needed to reduce the prevalence of niches and prevent complications in subsequent pregnancies such as caesarean scar pregnancies.

The definition, diagnosis, and symptoms of the uterine niche - A systematic review

Of all neonates, 21% are delivered by cesarean section (CS). A long-term maternal complication of an SC is a uterine niche. The aim of this review is to provide an overview of the current literature on imaging techniques and niche-related symptomatology. We performed systematic searches on imaging and niche symptoms. For both searches, 87 new studies were included. Niche evaluation by transvaginal sonography (TVS) or contrast sonohysterography (SHG) proved superior over hysteroscopy or magnetic resonance imaging. Studies that used SHG in a random population identified a niche prevalence of 42%-84%. Niche prevalence differed based on niche definition, symptomatology, and imaging technique. Most studies reported an association with gynecological symptoms, poor reproductive outcomes, obstetrical complications, and reduced quality of life. In conclusion, non-invasive TVS and SHG are the superior imaging modalities to diagnose a niche. Niches are prevalent and strongly associated with gynecological symptoms and poor reproductive outcomes.