Among perinatal health issues, preterm birth is still the leading cause of disability and perinatal death [1] [2] . Preterm or premature birth is defined as a baby born alive, having a gestation period of less than 37 weeks, according to World Health Organization (WHO) [3] . In 2020, about 13.4 million preterm babies were born and the incidence rates of preterm birth are still increasing globally [4] . About 10.6% of infants are born with preterm birth globally, and the incidence rates vary from 8.7% to 13.4% across different regions [5] . In other words, about 12.9 million preterm deliveries are reported annually, leading to severe perinatal morbidity and mortality [6] . Prematurity is increasing globally, with 5-18% incidence rates in Western countries and 60% in South Asian and African countries [7] [8] . The major risk factors associated with preterm birth (PTB) are smoking, use of alcohol, use of illegal drugs, environmental factors, age of the mother and lack of care during pregnancy [9] . Several mechanisms initiate preterm labour syndromes such as uterine overdistension, infection or inflammation, stress, haemorrhage or ischemia, and immunologically mediated processes [10] . Preterm infants are at higher risk of developmental problems, health complications, and related mortality rather than healthy infants. Priorconization, other risk factors associated with preterm birth in patients are cervical length, and specimen volume. Preterm infants are at higher risk of getting complications such as poor body temperature regulation, impaired respiration, various infections, and difficulty in feeding [11] .

Over the past two decades, perinatal care has been improved, but still rates of preterm birth are increasing. Preterm infants are at higher risk of developmental problems, health complications, and related mortality rather than healthy infants The increasing prevalence rates of preterm births (PTM) and related complications emphasize the importance of diagnosis and suggest early treatment strategy for women at risk [12] . Various diagnostic and therapeutic interventions exist for optimal management of PTB, including reduction of physical activity, smoking cessation [13] , antibiotic treatment of bacterial vaginosis and screening of periodontal disease [14] . Transvaginal ultrasound measurement (TVS) of cervical length is considered as one of the most accurate techniques for prediction and management of women at PTB risk [15] .

Cervical insufficiency is defined as the dilation of the cervix prematurely in pregnancy. In other words, cervical insufficiency is the inability of the uterine cervix in the absence of symptoms or signs related to uterine contraction which causes an issue of retaining a pregnancy [16] . The common symptoms of cervical insufficiency are placenta abruption, premature rupture of membranes (PROM) and chorioamnionitis in the second trimester. Moreover, the risk factors linked with cervical insufficiency are obstetric lacerations, deficiencies in cervical elastin and collagen, conization, congenital mullerian and mechanical dilation of the cervix. It is reported that a structural deficiency in the cervix causes cervical insufficiency of the cervix. Preterm opening of the cervix raises a woman’s chance of preterm delivery significantly [17] .

There are two main types of treatment for cervical insufficiency (CI); conservative and surgery. Cervical cerclage is a surgical treatment of cervical insufficiency, done by sewing the cervix opening temporarily with stitches [18] . The cerclage is performed in the second trimester of pregnancy to enhance the capacity of the cervix for holding pregnancy that prevents preterm birth. Cervical cerclage (CC) treatments are of two types: emergency CC (ECC) and prophylactic CC (PCC) [19] . The methods commonly used for cervical cerclage are performed trans-vaginally or trans-abdominally. The point of consideration is that all treatment strategies are recommended after the diagnosis or previous history of painless cervical dilation in the second trimester of pregnancy. However, cervical insufficiency among women with no previous history can be diagnosed through ultrasonographical results of amniotic membrane bulging or short cervical length in the mid-second trimester [20] .

When the cervix has not yet been obliterated or dilated, the cerclage procedure is referred to as prophylactic cerclage. Prophylactic cerclage cervix is performed between 12 to 14 weeks (about 3 months) of pregnancy due to indication of cervix insufficiency from medical history and ultrasonography [21] . In patients who have had cervical insufficiency in the past, prophylactic cerclage may be recommended. In comparison to earlier, the emergency CC is performed after effacement and dilation [22] . While the conservative treatment strategies for cervical cerclage (CC) include pessary treatment, and expectant treatment. Additionally, Arabian cervical pessary and vaginal progesterone are effective preventive treatment strategies for women at PTB risk [23] .

Other studies showed positive outcomes by conservative management strategies such as progesterone therapy to treat short cervical length. Due to safety and efficacy, the conservative management is prioritized over emergency cerclage to treat amniotic membrane bulging among pregnant women to prevent severe complications [24] . On the other hand, severe complications are associated with emergency cerclage, having bulged amniotic membrane and these are PROM, cervical bleeding, and chorioamnionitis, even can lead to more foetal loss as compared to prophylactic cerclage. Moreover, there are still controversies related to the efficacy of emergency cerclage as compared to other treatment strategies for cervical insufficiencies among pregnant women [25] .

Several studies reported that prophylactic cervical cerclage decreases the prevalence of preterm birth as well as linked severe complications and increases the length of pregnancy effectively. The effective clinical outcomes of prophylactic cervical cerclage are reported in gestational age at delivery, length of hospital stay after surgery, live births, operative time, and preterm birth. One surgical procedure that works well to stop late foetal loss or recurrent abortion is cervical prophylactic cervical cerclage [11] - [16] .

Since several studies have reported the efficacy of cervical cerclage either by prophylactic or emergency procedure. But very few studies have been conducted on the efficacy and safety of prophylactic cervical cerclage in pregnant women with cervical incompetency. Therefore, the recent meta-analysis aimed to evaluate the effectiveness of prophylactic cervical cerclage in improving outcomes among pregnant women with cervical insufficiency.

The “Reporting Items for Systematic Review and Meta-Analysis (PRISMA)" guidelines were followed for conducting a recent meta-analysis according to research aims [26] - [28] .

The recent meta-analysis was performed to evaluate the effectiveness of Prophylactic or early or elective cervical cerclage in comparison to other treatments for cervical insufficiency among the pregnant women. Other standard therapeutic strategies against prophylactic cervical cerclage were conservative treatment, and emergency or therapeutic cervical cerclage to treat cervical incompetence. The findings reported that prophylactic cervical cerclage resulted in prolonged pregnancy duration after delivery in weeks as compared to emergency or therapeutic cervical cerclage, as evaluated by mean difference among intervention and placebo groups. Other outcomes such as low rates of preterm births [32] [34] [35] [37] [39] , number of deliveries > 37 weeks [32] [34] [36] and abortion rates [35] [39] among those pregnant women receiving prophylactic cervical cerclage as compared to conservative treatments or emergency cervical cerclage. Furthermore, the mean difference in prolongation of delivery weeks (Mean difference = 1.05; Cl: 0.81 to 1.29: p > 0.00001), number of deliveries > 37 weeks (OR = 0.59; Cl: 0.19 to 1.84: p > 0.006), number of preterm births (OR = 0.73; Cl: 0.42 to 1.28: p > 0.50) number of live births (OR = 7.94; Cl: 4.42 to 15.28: p > 0.74) in number of abortions (OR = 0.21; Cl: 0.42 to 1.28: p > 0.16) among pregnant women receiving prophylactic cervical cerclage as compared to other treatment strategies. Additionally, the rates of live births among prophylactic cervical cerclage were higher than other interventions. Overall, recent meta-analysis evaluated higher success rates by implementation of prophylactic cervical intervention due to earlier indications of cervical insufficiency and its diagnosis to prevent poor pregnancy related outcomes. The prophylactic cervical cerclage is recommended also on basis of previous abortion history or painless dilation, leading to preterm births or abortions among pregnant women [22] .

Up to 1% of maternal populations may have cervical insufficiency, consequently it’s a condition that occurs frequently enough that it is advised to address that the issues with its management were beyond due. Cervical cerclage has been a part of obstetric practice for more than a century, but its purpose and appropriate uses are still unclear and up for debate, with significant variances in application across various clinical contexts [40] . The uncertainty around the identification of individuals who will genuinely benefit from cerclage (i.e., those with actual elevated risk of preterm delivery or cervical insufficiency) contributes to the lack of clarity surrounding the procedure. Cervical directing, shortening, for and overt dilatation are signs in the first trimester of pregnancy that may point to probable cervical insufficiency [41] . Even without it, A cervical length measured by ultrasonography that is less than 25 mm before 27 weeks of pregnancy is known as funnelling, and it raises the risk of miscarriage or preterm delivery. Cervical insufficiency must be screened for, or its likelihood predicted in the absence of a valid diagnostic test. The foundation of this procedure is the determination and acknowledgement of significant risk factors in the woman’s medical history and the index pregnancy. Preterm births or losses in the second trimester of pregnancies are the most common indicators in the patient’s medical history that point to a possible danger. Yet it should be highlighted that there may occasionally be a range among preterm and cervical insufficiency [24] .

In others, birth and labour are two separate and unconnected procedures. Cervical insufficiency risk is not always indicated by previous experience of preterm labour or a determination of risk factors for preterm birth. Alfirevic [42] reported the study to evaluate the risk of cervical insufficiency and recommendation of cervical insufficiency or other conservative treatments such as progesterone to avoid preterm birth. The results of this investigation are a little contradictory, showing that while cerclage reduces the rates of preterm births statistically significantly, it does not influence maternal death or morbidity. Additionally, cerclage was linked to higher rates of maternal illness and Caesarean sections, the latter of which may potentially be responsible for a non-significant rise in respiratory morbidity among babies born to women who had cerclages.

Liu et al., [43] conducted an update meta-analysis and systematic review to evaluate efficacy of prophylactic cervical cerclage in twin pregnancies by comparing 8578 non cerclage and 726 patients with earlier cervical cerclage. The findings reported that prophylactic cervical cerclage was linked to a significant decrease in PTB, nevertheless, only in twin pregnancies with a cervical length less than 15 mm. In twin pregnancies, there is still conflicting evidence about the safety and efficacy of cervical cerclage on mother and newborn outcomes. Another study by Belej-Rak [44] evaluated effectiveness of prophylactic cervical cerclage on the basis of sonographic results of cervix shortness through 6 studies. Cerclage had no statistically significant impact on the incidence of preterm labour, newborn mortality or complications, gestational age at birth, or length of labour. Preterm delivery was defined as those occurring at 37, 34, 32, and 28 weeks of gestation. With cerclage, birth weight was substantially higher than without. Cervical cerclage is not recommended for a short cervix identified sonographically, according to the current data. It will take a randomized controlled trial to ascertain whether this technique would lessen unfavourable outcomes for newborns. Li et al., [45] estimated the efficacy of prophylactic cervical cerclage in extending the prolongation of pregnancy and reducing risk preterm births or abortion. The findings of meta-analysis showed that in doublets with a cervical length of less than 15 mm or a dilated cervix larger than 10 mm, cerclage implantation prolongs pregnancy and reduces the risk of premature birth. According to recent research, the advantages of two pregnancies with normal cervical length and history- or twins alone-indicated cerclage are less definite. Drakeley et al., [26] conducted the research on evaluation of efficacy of prophylactic cervical cerclage in improving outcomes among pregnant women with cervical insufficiency. About 2175 pregnant women from six trials were analysed through pooled analysis. The findings reported that prophylactic cerclage is not beneficial in avoiding premature delivery in women who are at low or medium risk of miscarrying a second child. Moreover, the use of cerclage in women whose ultrasounds show a short cervix is still unclear, nevertheless. Another meta-analysis conducted by Wei and Wang [27] reported the efficacy of emergency cervical cerclage in terms of improvements in neonatal survival rates and gestational period among pregnant women with cervical insufficiency as compared to expectant treatment. The underlying principle accounting for clinical role of prophylactic cervical cerclage among pregnant women in comparison to other treatment strategies for cervical insufficiency was conducted for the first time. Several previous studies reported combined effects of prophylactic cervical cerclage and emergency cervical cerclage against conservative methods [42] [43] . Now, it is need of hour to manage the cervical insufficiency before 28 weeks of pregnancy by proper diagnosis and studying underlying pathophysiology of cervical insufficiency among pregnant women. Growing knowledge of pathophysiology offers an additional rationale for investigating into cerclage’s potential application in the treatment of cervical insufficiency [46] .

The recent meta-analysis has used more recent research to evaluate the efficacy of prophylactic cervical cerclage, as it is done on basis of diagnosis of dilation and shorter cervical length, not after 28th week of gestation. We used ROBINS-I to evaluate the methodological risk of bias to ensure quality of including studies. The publication bias of included studies was robust which ensured quality of recent meta-analysis. We conducted pooled analysis of rates of preterm births, live births, number of deliveries > 37 weeks. However, there are few limitations in recent meta-analysis which should be considered. Firstly, a limited number of studies were available on comparison of prophylactic’s efficacy with other treatment strategies. Secondly all studies were retrospective studies or non-randomized controlled trials, as it should include randomized controlled trial to produce heterogeneity. Even though we used stringent inclusion and exclusion standards, it’s probable that we overlooked some additional biological elements that might have impacted conception result. Fourth, we limited the scope of our analysis to publications that were composed in English.

In conclusion, a recent meta-analysis suggested that prophylactic cervical cerclage reduces the rates of preterm birth, abortion rates, number of deliveries > 37 weeks and other complications as compared to the other cervical cerclage types and conservative treatments. Additionally, the rates of live births and prolongation in gestational weeks were increased after prophylactic cervical cerclage as compared to other strategies among pregnant women with cervical incompetence. Further studies should be conducted with a larger sample size to evaluate other clinical outcomes after the implication of prophylactic cerclage as compared to other treatment strategies to treat cervical insufficiency.