Could a cervical occlusion suture be effective at improving perinatal outcome?

Cerclage prevents ascending intrauterine infection in pregnant mice

BACKGROUND

The treatment for cervical insufficiency is cerclage surgery. Although cerclage is a common therapy for prevention of preterm birth, there is no consensus about its mechanism of efficacy. Previous investigators have hypothesized that cerclage prevents preterm birth by improving the cervical barrier to ascending infection. However, this hypothesis is difficult to study in human pregnancy.

OBJECTIVE

In a mouse model of ascending infection, we hypothesized that a cerclage improves the cervical barrier leading to decreased ascending intrauterine infection and inflammation. An abdominal cerclage was studied because a vaginal cerclage is not feasible in mice.

STUDY DESIGN

To perform an abdominal cerclage, laparotomy was performed on timed, pregnant C57BL/6 mice on gestational day 10 (E10). A 6-0 silk suture was placed around the cervix just below the junction of the 2 uterine horns. Sham controls received the same surgery, but no cerclage was placed. To track ascending infection nonpathogenic E coli K12 was genetically modified to express bioluminescence. On E15, bioluminescent E coli K12 (20 μL of 1×109 bacteria) was inoculated into the vagina. Whole-body bioluminescence imaging was performed 0.5 hours and 24 hours after inoculation. To assess intrauterine inflammation, pathogenic E coli K1 was used. On E15, bacterial inoculums of E coli K1 (20 μL of 1×104 bacteria) were vaginally administered. Samples of uterus, placenta, and fetal membranes were collected 24 hours after inoculation. Gene expression of inflammation-related proteins was compared between 3 groups: (1) sham control surgery + inoculation of phosphate-buffered saline (PBS), (2) sham control surgery + inoculation of E coli K1, and (3) cerclage surgery + inoculation of E coli K1.

RESULTS

Abdominal cerclage was well tolerated. No cases of preterm birth were seen following abdominal cerclage. Whole-body bioluminescent imaging performed 0.5 hours post inoculation showed a strong luminescence signal in the vaginal region of mice in both control and experimental groups indicating successful bacteria inoculation. Twenty-four hours after inoculation, bioluminescent signal was seen ascending into the uterine horns in all control mice. However, in mice with abdominal cerclages, no bioluminescent signal was seen after 24 hours. When the reproductive tissues were imaged separately in control mice, strong bioluminescence signal was detected in the placenta, fetal membranes, and uterus. Gene expression studies showed that cerclage significantly decreased the expression of inflammatory proteins induced by E coli K1 in the uterus, placenta, and fetal membranes.

CONCLUSION

In this mouse model of ascending intrauterine infection, abdominal cerclage prevented ascending infection of E coli. In addition, abdominal cerclage prevented expression of inflammatory cytokines in the uterus, placenta, and membranes of mice. The study provides evidence for a potential mechanism of cerclage success in human pregnancy.

Microenvironment of the Lower Reproductive Tract: Focus on the Cervical Mucus Plug

The female lower reproductive tract microbiota is a complex ecosystem comprising various microorganisms that play a pivotal role in maintaining women's reproductive well-being. During pregnancy, the vaginal microbiota undergoes dynamic changes that are important for a successful gestation. This review summarizes the implications of the cervical mucus plug microenvironment and its profound impact on reproductive health. Further, the symbiotic relationship between the vaginal microbiome and the cervical mucus plug is highlighted, with a special emphasis on how this natural barrier serves as a guardian against ascending infections. Understanding this complex host-microbes interplay could pave the way for innovative approaches to improve women's reproductive health and fertility.

Comparison of two stitches versus one stitch for emergency cervical cerclage to prevent preterm birth in singleton pregnancies

OBJECTIVE

To compare the efficacy of two stitches versus one stitch in women with emergency cervical cerclage.

METHODS

A retrospective case-control study of 26 women with singleton pregnancies who underwent emergency cervical cerclage before 26 weeks. A comparison was made between patients with two stitches versus one stitch at the time of cervical cerclage placement. The primary outcome was gestational age (GA) at delivery and preterm birth (PTB) before 37, 34, 32, 28, and 24 weeks.

RESULTS

Average GA at delivery in the two-stitches group was significantly greater than in the one-stitch group (32.71 ± 5.54 weeks vs 27.99 ± 4.70 weeks, P = 0.028). There were significant decreases in the incidence of spontaneous PTB at <34 weeks and less than 32 weeks in the two-stitches group (P = 0.034; P = 0.013, respectively). The neonatal intensive care unit (NICU) admissions rate and length of stay in the NICU in the two-stitches group were significantly reduced (P = 0.035 and P = 0.018, respectively). However, there was no significant difference in neonatal mortality between the two groups.

CONCLUSION

Compared with emergency cervical cerclage placement with one stitch, the procedure with two stitches can prolong the pregnancy and improve the neonatal prognosis more effectively.

[Cervical cerclage]

Cervical cerclage aims to strengthen not only the mechanical properties of the cervix, but also its immunological and anti-infectious functions. The demonstration of a strong interrelation between cervical insufficiency as well as decreased cervical length at endo-vaginal ultrasonography and infection has changed the indications cerclage. Actually we can distinguish three indications for cerclage: prophylactic, for obstetrical history; therapeutic, for shortened cervical length at ultrasonography in patients at risk and; emergency cerclage in case of threatening cervix at physical examination. The McDonald's technique is the most recommended. In case of failure, it is proposed to realize cerclage at a higher level on the cervix either by vaginal or abdominal route.

[Management of patients with a history of late abortion or very premature delivery]

Patients have a very late abortion or premature delivery in 2-3 % of pregnancies. Management in a subsequent pregnancy should seek an infection, a fetal cause (aneuploidy, malformation syndrome, intrauterine death) or vascular pathology (preeclampsia, IUGR, intrauterine death). In women with a late abortion or very premature childbirth history, several preventive treatments of prematurity are now available. The main cause of prematurity is ascending infection from the vagina. Cerclage or pessary is designed to better isolate the uterine cavity. Their effectiveness has been validated in patients for whom the repeated measurement of cervical length by transvaginal ultrasound shows a cervical length <25mm. Early pregnancy vaginosis and treatment with Dalacin(®) seem to significantly reduce the risk of prematurity. Finally, the routine administration of intramuscular or vaginal progesterone at the beginning of the 2(nd) quarter also proved effective in several randomized studies.

Viable extreme preterm birth and some neonatal outcomes in double cerclage versus traditional cerclage: a randomized clinical trial

The pregnant women at higher risk of preterm labor, referred to the perinatal clinic of Kosar University Hospital in Urmia district of Iran, were enrolled into a parallel randomized clinical trial. In the investigational arm of the clinical trial, a double cervical cerclage procedure was performed addition to McDonald cerclage. In the control group however, only McDonald cerclage was performed. Extreme preterm labor (GA < 33 weeks) was the primary endpoint of this clinical trial. Age, gestational age at cerclage time, and gravidity were not found to be statistically different between the groups. Means of gestational age were 37.4 and 36.2 weeks, respectively, for the investigational and control groups. The gestational age was 1.2 weeks longer for double cerclage group but the difference was not found to be statistically significant. Preterm birth before 33 weeks of gestation was not experienced by any of the patients who received double cerclage, but five women in control group developed such an extreme preterm labor (P < 0.05). The absolute risk reduction in using double cerclage over traditional method was 18 percent (95% confidence interval, 4%-32%). Double cerclage appeared to have higher efficacy than traditional cerclage in preventing preterm labor <33 weeks of gestation.

Fertility preserving surgery for carcinoma of the cervix

PURPOSE OF REVIEW

Cervical cancer remains the second most common female malignancy. Screening programmes have reduced the overall incidence, predominantly in the western world; however, this has led to a disproportionate rise in the incidence of early-stage disease, with a related increase in demand, for fertility-sparing techniques to be developed.

RECENT FINDINGS

Standard treatment for cervical cancer compromises fertility. A radical wide local excision of carefully selected early-stage tumours will allow conservation of the body of the uterus with a vaginoisthmic anastomosis enabling continuity of the vagina to be preserved following insertion of an isthmic cerclage suture. Pelvic node dissection may be performed at the same time by laparoscopic techniques. Over 900 cases have been performed and reported in the literature worldwide. Most have been carried out vaginally (radical vaginal trachelectomy and laparoscopic pelvic node dissection). A smaller number have been performed abdominally. There have been over 300 pregnancies reported with 196 live births. There has been a 10% significant prematurity rate with birth prior to 32 weeks. There have been 31 recurrences (4%), and 16 deaths (2%).

SUMMARY

Radical vaginal trachelectomy appears safe when performed in centres with appropriate experience of radical vaginal surgery and laparoscopic techniques. The impact of this new approach questions traditional teaching, thus preserving potential fertility in up until now impossible circumstances.

A potential role for tissue kallikrein-related peptidases in human cervico-vaginal physiology

Human tissue kallikrein-related peptidases (KLK) are a family of 15 genes located on chromosome 19q13.4 that encode secreted serine proteases with trypsin- and/or chymotrypsin-like activity. Relatively large levels of many KLKs are present in human cervico-vaginal fluid (CVF) and in the supernatant of cultured human vaginal epithelial cells. Many KLKs are also hormonally regulated in vaginal epithelial cells, particularly by glucocorticoids and estrogens. The physiological role of KLK in the vagina is currently unknown; however, analysis of the CVF proteome has revealed clues for potential KLK functions in this environment. Here, we detail potential roles for KLKs in cervico-vaginal physiology. First, we suggest that KLKs play a role in the vagina similar to their role in skin physiology: (1) in the desquamation of vaginal epithelial cells, similar to their activity in the desquamation of skin corneocytes; and (2) in their ability to activate antimicrobial proteins in CVF as they do in sweat. Consequently, we hypothesize that dysregulated KLK expression in the vagina could lead to the development of pathological conditions such as desquamative inflammatory vaginitis. Second, we propose that KLKs may play a role in premature rupture of membranes and pre-term birth through their cleavage of fetal membrane extracellular matrix proteins.