History of cervical insufficiency increases the risk of pelvic organ prolapse and stress urinary incontinence in parous women

Unravelling the genetic landscape of cervical insufficiency: Insights into connective tissue dysfunction and hormonal pathways

BACKGROUND

The intricate molecular pathways and genetic factors that underlie the pathophysiology of cervical insufficiency (CI) remain largely unknown and understudied.

METHODS

We sequenced exomes from 114 patients in Latvia and Lithuania, diagnosed with a short cervix, CI, or a history of CI in previous pregnancies. To probe the well-known link between CI and connective tissue dysfunction, we introduced a connective tissue dysfunction assessment questionnaire, incorporating Beighton and Brighton scores. The phenotypic data obtained from the questionnaire was correlated with the number of rare damaging variants identified in genes associated with connective tissue disorders (in silico NGS panel). SKAT, SKAT-O, and burden tests were performed to identify genes associated with CI without a priori hypotheses. Pathway enrichment analysis was conducted using both targeted and genome-wide approaches.

RESULTS

No patient could be assigned monogenic connective tissue disorder neither genetically, neither clinically upon clinical geneticist evaluation. Expanding our exploration to a genome-wide perspective, pathway enrichment analysis replicated the significance of extracellular matrix-related pathways as important contributors to CI's development. A genome-wide burden analysis unveiled a statistically significant prevalence of rare damaging variants in genes and pathways associated with steroids (p-adj = 5.37E-06). Rare damaging variants, absent in controls (internal database, n = 588), in the progesterone receptor (PGR) (six patients) and glucocorticoid receptor (NR3C1) (two patients) genes were identified within key functional domains, potentially disrupting the receptors' affinity for DNA or ligands.

CONCLUSION

Cervical insufficiency in non-syndromic patients is not attributed to a single connective tissue gene variant in a Mendelian fashion but rather to the cumulative effect of multiple inherited gene variants highlighting the significance of the connective tissue pathway in the multifactorial nature of CI. PGR or NR3C1 variants may contribute to the pathophysiology of CI and/or preterm birth through the impaired progesterone action pathways, opening new perspectives for targeted interventions and enhanced clinical management strategies of this condition.

Systems biology approach: identification of hub genes, signaling pathways, and molecular docking of COL1A1 gene in cervical insufficiency

The collagen type I alpha 1 (COL1A1, OMIM #120,150) gene, encoding the alpha-1 chain of type I collagen (UniProt #P02452), plays a key role in life-homeostasis due to its remarkable involvement in collagen synthesis. It is a promising candidate gene implicated in the pathogenesis of cervical insufficiency (CI). This study aimed to identify genetic variations within the COL1A1 gene that contribute to the development of CI. Polymerase chain reaction (PCR) and amplicon sequencing were implemented for single nucleotide polymorphisms (SNPs) detection (+ 1245G/T, SP1 rs1800012), which revealed wild-type sequence for targeted SNPs in enrolled proband indicated negative results regarding COL1A1 gene involvement for current form of CI. It allows further investigation of other closely connected genes probed in this study. Computational approaches viz. Protein-protein interaction (PPI), gene ontology (GO), and pathway participation were used to identify the crucial hub genes and signaling pathways for COL1A1 and CI. Using the Yet Another Scientific Artificial Reality Application (YASARA) software, molecular docking, and molecular dynamic (MD) simulation with the oxytocin (CID 439,302), estradiol (CID 129,728,744), progesterone (CID 5994) and hydroxyprogesterone (CID 150,788) were done. Interactive bioinformatics analysis demonstrated that the COL1A1 and more than 10 collagen sister genes had a strong connection with CI. In sum, the findings of this study provide insights into a modus operandi that can be utilized to illuminate the path toward studying sister genes and smooth diagnosis of CI. These findings have implications for understanding the foundational process of the condition and potentially developing screening, diagnostic, and therapeutic interventions.

Graphical Abstract

Cervical insufficiency a prologue for future pelvic organ prolapse?

BACKGROUND

Preliminary evidence suggests that women with cervical oss insufficiency may have an increased risk to develop pelvic organ prolapse later in life, suggesting a common underlying collagen-oriented mechanism.

OBJECTIVE

The objective of this study was to determine the association between cervical oss insufficiency and the subsequent development of pelvic organ prolapse.

STUDY DESIGN

A matched, case-control study, including women who delivered at the Soroka University Medical Center. Cases were women diagnosed or treated with pelvic organ prolapse (n = 1463), and controls were a representative sample of women of the same age group without pelvic organ prolapse (n = 5637). The association between pelvic organ prolapse and prior preterm birth was tested. Univariate analysis was performed using a conditional logistic regression to assess the association between preterm labor and pelvic organ prolapse. Statistically and clinically significant variables in the univariate analysis were included in the multivariable regression.

RESULTS

The rate of spontaneous preterm birth did not differ between the study groups [pelvic organ prolapse - 4.0% (59/1463) vs. non- pelvic organ prolapse - 4.9% (276/5637), p = 0.16]. The median number of preterm births was higher among women without pelvic organ prolapse (controls) than in those with pelvic organ prolapse (cases) (p = 0.004). Among those who delivered preterm, the individual proportion of preterm deliveries was higher among the controls' group (p = 0.03). Similarly, the rate of cesarean deliveries was also higher among the controls group (p = 0.003). The rate of small for gestational age neonates was higher in the controls group (p = 0.0007), while that of large for gestational age neonates was higher in the case group (p = 0.02). In the univariate analysis, birthweight, vaginal delivery, and prior surgery were associated with subsequent development of pelvic organ prolapse. The multivariable analysis exhibited the same association- having birthweight, vaginal delivery, and all types of prior surgery independently associated with subsequent development of pelvic organ prolapse.

CONCLUSIONS

Obstetrics characteristics associated with pelvic organ prolapse included vaginal delivery and birthweight along with non-obstetrical factors such as prior surgery. There was no association between preterm birth and subsequent development of pelvic organ prolapse. Our findings suggest that the effort during labor at term required for the delivery of appropriate for gestational age or large for gestational age newborns affects the pelvic floor and is a major contributor for the subsequent development of pelvic organ prolapse.

Sonographic and genetic findings in a case of asymptomatic spontaneous uterine rupture

An asymptomatic 25-year-old G4P0120 with history significant for cervical insufficiency and classical cesarean delivery 12.5 months prior to conception underwent routine transabdominal ultrasound at 36w4d; umbilical cord was found to be protruding into a fluid-filled pouch extruding from the lower uterine segment. During emergent cesarean delivery, a full-thickness uterine rupture was confirmed; the fetal cranium and umbilical cord were extrauterine. Maternal genotype revealed greater than expected minor allele frequencies for several collagen genes. Maternal gene expression (mRNA) and corresponding microRNA expression of these collagen genes differed several-fold between her G3 (cervical insufficiency, classical cesarean delivery) and G4 (uterine rupture) pregnancies. This case highlights that (1) cervical insufficiency, poor myometrial wound healing, and uterine rupture may co-occur and pathophysiology may be related to collagen abnormalities and (2) asymptomatic uterine rupture can be detected sonographically, even in late pregnancy. Clinicians should remain vigilant for the possibility of uterine rupture, particularly among high-risk patients.

Are women with cervical incompetence at a higher risk of experiencing urinary and pelvic organ prolapse symptoms?

INTRODUCTION AND HYPOTHESIS

Pelvic organ prolapse (POP) and lower urinary tract symptoms (LUTs), in addition to cervical incompetence, have a multifactorial etiology. Connective tissue disorders are common risk factors in both entities. The objective of this study was to compare long-term urinary and pelvic organ prolapse-related symptoms in patients who experienced cervical incompetence and those who did not.

METHODS

In this historical prospective cohort, analysis of cervical incompetence cases from one medical center between 2006 and 2009 were compared with a matched control group. All cases included a minimum 7-year follow-up. Symptoms of urinary and prolapse-related complaints during follow-up were evaluated based on the Pelvic Floor Distress Inventory-20 questionnaire.

RESULTS

The study group comprised 37 women who experienced cervical incompetence matched to 34 consecutive controls. There was no difference between the groups in demographic or obstetric characteristics, except for a higher cesarean section rate and earlier deliveries among women with cervical incompetence. On assessment of patient's symptoms, during follow-up, the average Pelvic Organ Prolapse Distress Inventory-6 score was significantly higher in patients who experienced cervical incompetence than in controls (15.0 ± 26.1 vs 1.7 ± 7.1 respectively, p = 0.034). Urinary complaints, as reflected by the Urinary Distress Inventory-6 index, were also more common in women with cervical incompetence (17.9 ± 19.1 vs 3.9 ± 7.3 p = 0.027).

CONCLUSIONS

Women with a history of cervical incompetence experienced a higher rate of pelvic organ prolapse and urinary symptoms compared with women who had no cervical insufficiency.