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 Table of Contents  
ORIGINAL ARTICLE
Year : 2015  |  Volume : 28  |  Issue : 4  |  Page : 864-872

Vaginal progesterone and cervical cerclage for preterm labor prevention and their impact on perinatal outcome


Department of Obstetrics and Gynecology, Faculty of Medicine, Menoufia University, Menoufia, Egypt

Date of Submission09-Nov-2014
Date of Acceptance18-Jan-2015
Date of Web Publication12-Jan-2016

Correspondence Address:
Shaimaa M Mnasir
Flat #1303, Lights Tower, 47 Gamila Bu Hraid St., Alexandria, 21511
Egypt
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/1110-2098.173605

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  Abstract 

Objective
The main aim of this study was to evaluate the efficacy of progesterone supplementation, cervical cerclage, or a combination of both in the prevention of preterm labor (PTL) and their impact on the perinatal outcome.
Background
PTL is defined as the presence of uterine contractions of sufficient frequency and intensity to effect progressive effacement and dilation of the cervix before term gestation (between 20 and 37 weeks). Preterm delivery occurs in 5-13% of pregnancies before 37 weeks' gestation.
Patients and methods
The present study was designed as a randomized clinical trial. Only 147 women who fulfilled our inclusion criteria (singleton pregnancy and a history of spontaneous PTL, twin or triplet gestations, sonographic cervical length <25 mm in mid trimester, and gestational age at the first antenatal visit of 12-16 weeks) were assigned randomly to the study. Forty-nine women received vaginal progesterone, 49 women were subjected to cervical cerclage, and 48 women received vaginal progesterone and cerclage.
The primary outcome parameter was spontaneous delivery at less than 37 weeks' gestation. The secondary outcome parameter was spontaneous delivery at 34 or less weeks' gestation. The neonatal morbidity parameters were birth weight, Apgar score, and neonatal intensive care unit admission.
Results
The primary and secondary outcome parameters were significantly improved in the combination group (P = 0.005 and 0.008, respectively); also, the neonatal morbidity parameters (birth weight, Apgar score, and neonatal intensive care unit admission) were significantly improved in the combination group (P = 0.047, 0.003, and 0.002, respectively).
Conclusion
The combination of vaginal progesterone and cerclage was found to be significantly more effective in preventing PTL and in improving the perinatal outcomes in the high-risk groups.

Keywords: cerclage, neonatal intensive care unit, vaginal progesterone


How to cite this article:
Abd Elaal NK, Sanad ZF, Dawod RM, Mnasir SM. Vaginal progesterone and cervical cerclage for preterm labor prevention and their impact on perinatal outcome. Menoufia Med J 2015;28:864-72

How to cite this URL:
Abd Elaal NK, Sanad ZF, Dawod RM, Mnasir SM. Vaginal progesterone and cervical cerclage for preterm labor prevention and their impact on perinatal outcome. Menoufia Med J [serial online] 2015 [cited 2020 Mar 30];28:864-72. Available from: http://www.mmj.eg.net/text.asp?2015/28/4/864/173605


  Introduction Top


Preterm labor (PTL) occurs in 5-13% of pregnancies before 37 weeks' gestation. The incidence of early PTL (<34 gestational weeks) is 1-3.6% [1] .

Fifteen million babies are born prematurely each year, causing about one million of the three million neonatal deaths that occur annually [2],[3],[4] . Prematurity is now the second leading cause of death in children younger than 5 years of age and the leading cause of death in the first month of life [5],[6] . There appear to be two interventions that may reduce the rate of PTL in patients with a history of preterm birth (PTB) and a cervix of less than 25 mm: vaginal progesterone administration or cervical cerclage [7] .

Two independent randomized clinical trials [8],[9],[10],[11] and an individual patient data (IPD) meta-analysis showed that vaginal progesterone decreases the rate of PTL and neonatal morbidity/mortality in women with a sonographic short cervix. This is the case for patients with or without a history of PTB [12] . The placement of a cervical cerclage appears to be indicated in patients with acute cervical insufficiency [13],[14],[15],[16],[17],[18],[19],[20] and perhaps, in some with a history of PTB and a sonographic short cervix of less than 25 mm [21],[22],[23],[24] .

Recently, two professional organizations have recommended that cerclage may be considered for the treatment of women with a singleton gestation, previous spontaneous PTB, and a cervical length less than 25 mm at less than 24 weeks of gestation [25],[26] . This recommendation was made mainly on the basis of an IPD meta-analysis of randomized-controlled trials that show that cerclage is associated with a statistically significant reduction in the risk of PTB at less than 37, less than 35, less than 32, less than 28, and less than 24 weeks of gestation, and composite perinatal morbidity and mortality compared with no cerclage [23] . However, another IPD meta-analysis reported that vaginal administration of progesterone to women with a sonographic short cervix (<25 mm) in the mid trimester significantly decreased the risk of PTB at less than 35, less than 34, less than 33, less than 30, and less than 28 weeks of gestation and composite neonatal morbidity and mortality compared with placebo [13] .

In addition, a subgroup analysis showed that administration of vaginal progesterone was associated with a significant reduction in the risk of PTL at less than 33 weeks of gestation and composite neonatal morbidity and mortality in women with a short cervix (<25 mm), singleton gestation, and previous spontaneous PTL [12] .

The availability of vaginal progesterone and cerclage for the prevention of PTL in women with a short cervix, singleton gestation, and previous spontaneous PTB could result in a dilemma for physicians and patients on the optimal choice of treatment [27] . Thus far, there are no randomized-controlled trials comparing vaginal progesterone and cerclage directly [28] .

Twin pregnancies with or without previous PTL and short cervical length, either vaginal progesterone or cervical cerclage, are not recommended and have not been shown to reduce the risk of PTL [29],[30],[31] . Cervical cerclage may even increase the risk of PTL [23] . There is evidence that vaginal progesterone may reduce neonatal morbidity and mortality [12] .

The aim of this study was to evaluate the efficacy of progesterone supplementation, cervical cerclage, or a combination of both in the prevention of PTL and their impact on the perinatal outcome.


  Patients and methods Top


The present study was designed as a randomized clinical study to evaluate the efficacy of progesterone supplementation, cervical cerclage, or their combination in the prevention of PTL and their impact on the perinatal outcome. Two hundred and three pregnant women at high risk of PTL were chosen from the outpatient clinics at Dar Ismail Hospital form April 2013 to June 2014. Fifty-seven women were excluded (seven women because of age <35 years, three women carrying babies with congenital anomalies, three women with chronic hypertension, four women with diabetes mellitus, two women with uterine fibroids, three women with threatened abortion, one woman with a mitral stenosis, three women with severe anemia, two women with gestational age at the first visit of 17 and 19 weeks) as shown in the flow chart of participants ([Figure 1]). Only 146 women who fulfilled our inclusion criteria (singleton pregnancy, history of spontaneous PTL, twin or triplet gestations, sonographic cervical length <25 mm in mid trimester, and gestational age at the first antenatal visit of 12-16 weeks) were assigned randomly to the study (closed envelopes). Forty-nine closed envelopes had vaginal progesterone written and hidden inside, 49 closed envelopes had cervical cerclage written and hidden inside, and 48 closed envelopes had their combination written and hidden inside. Woman, after they had provided consent to participate, were asked to choose one closed envelope.
Figure 1 Flow chart of participants. IUFD: intrauterine fetal death.



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Forty-nine women received vaginal progesterone, 49 women were subjected to cervical cerclage, and 48 women received both vaginal progesterone and cervical cerclage. All eligible women were followed up clinically and by ultrasonography every 2 weeks till delivery.

The primary outcome was spontaneous delivery at less than 37 weeks' gestation. The secondary outcome was spontaneous delivery at 34 or less weeks' gestation.

The neonatal morbidity parameters were birth weight, Apgar score, and neonatal intensive care unit (NICU) admission.

The final analysis of the results included only 126 women who completed the study. There were 42 women in the progesterone group. Seven women dropped out; four women were lost to follow-up, two women were excluded because of a diagnosis of placental abruption, and one woman had preeclampsia.

Of the 41 women in the cerclage group, eight dropped out (four women refused to undergo surgery, three were lost to follow-up, and one had intra uterine fetal death).

There were 43 women in the combination group. Five women dropped out (two women refused to undergo surgery, two were lost to follow-up, and one had preeclampsia) as shown in the flow chart of participants ([Figure 1]).

The results were analyzed as follows:

  1. All women in the three study groups.
  2. Women with multifetal gestations.


Statistical analysis

Data were statistically described in terms of mean ± SD. Comparison of numerical variables between the study groups was carried out using the one-way analysis of variance test with post-hoc multiple two-group comparisons. For comparison of categorical data, the χ2 -test was performed. The exact test was used when the expected frequency was less than 5. P values less than 0.05 were considered statistically significant. All statistical calculations were carried out using the computer program statistical package for the social science (SPSS, version 15; SPSS Inc., Chicago, Illinois, USA) for Microsoft Windows.


  Results Top


Analysis of the results of all women in the three study groups

Demographic and obstetric characteristics of pregnant women included in the study

There was no statistically significant difference among the three study groups with respect to the age of pregnant women, gravidity, parity, number of abortions, number of previous spontaneous PTL ([Table 1]), and the number of fetuses (singleton, twins, or triplets) (P < 0.05).
Table 1 Comparison of demographic, obstetric characteristics, and gestational age at delivery among the three study groups


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Gestational age at delivery characteristics of pregnant women included in the study

The mean gestational age improved in the combination group by about 2 weeks ([Figure 2]). The gestational age at delivery was significantly higher in the combination group than that in the progesterone and cerclage groups (F = 8.528, P < 0.001). Multiple comparisons showed that the difference in gestational age was not statistically significant between the progesterone and the cerclage groups (T = 0.092, P = 1.000), statistically significant between the combination and the cerclage groups (T = 1.843, P = 0.002), and statistically significant between the combination and the progesterone groups (T = 1.915, P = 0.001) ([Table 1]).
Figure 2 Mean gestational age at delivery among the three study groups.



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The rate of PTL less than 37 weeks and 34 weeks or less was significantly lower in the combination group than that in the progesterone and cerclage groups (χ2 = 10.662, 9.594; P = 0.005, 0.008, respectively) ([Table 2] and [Figure 3]).
Figure 3 Percentage of secondary outcome (gestational age at delivery≤34 weeks) among the three study groups.



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Table 2 Comparison of the primary and secondary outcomes (gestational age at delivery <37 and ≤34 weeks, respectively) among the three study groups within all cases and within multifetal pregnancy


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Perinatal outcome characteristics

The mean birth weight was significantly higher in the combination group than that in the progesterone and cerclage groups (F = 3.104, P = 0.047) ([Table 3]).
Table 3 Comparison of birth weight and Apgar score among the study groups


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The mean Apgar score in the combination group was significantly higher than that in the progesterone and cerclage groups (F = 6.047, P = 0.003). Multiple comparisons showed that the difference in the Apgar score was not statistically significant between the progesterone and the cerclage groups (T = 0.041, P = 1.000), statistically significant between the combination and the cerclage groups (T = 1.252, P = 0.013), and statistically significant between the combination and the progesterone groups (T = 1.222, P = 0.023) ([Table 3]).

The number of neonates admitted to the NICU was significantly lower in the combination group than that in the progesterone and cerclage groups (χ2 = 12.756, P = 0.002) ([Table 4] and [Figure 4]).
Figure 4 Percentage of neonatal intensive care unit admission among the three study groups.



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Table 4 Comparison of neonatal intensive care unit admission among the three study groups


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Analysis of the results of women with multifetal gestations

Gestational age at delivery characteristics

The mean gestational age at delivery in twin and triplet gestations was significantly higher in the combination group than that in the progesterone and cerclage group (F = 7.688, P = 0.001) ([Figure 5]). Multiple comparisons showed that the difference in gestational age was not statistically significant between the progesterone and the cerclage groups (T = 0.051, P = 1.000), statistically significant between the combination and the cerclage groups (T = 2.176, P = 0.003), and statistically significant between the combination and the progesterone groups (T = 1.925, P = 0.007) ([Table 5]).
Figure 5 Mean gestational age in weeks at delivery within multifetal pregnancy among the three study groups.



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Table 5 Comparison of the gestational age at delivery within multifetal pregnancy among the three study groups


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The rate of preterm delivery less than 37 weeks and 34 weeks or less in twin and triplet gestations was significantly lower in the combination than that in the progesterone and cerclage groups (χ2 = 7.855, 7.451; P = 0.019, 0.024, respectively) ([Table 2] and [Figure 6]).
Figure 6 Percentage of secondary outcome (gestational age at delivery≤34 weeks) within multifetal pregnancy among the study groups.


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Perinatal outcome characteristics

The mean birth weight in twin and triplet gestations was significantly higher in the combination group than that in the progesterone and cerclage groups (F = 3.219, P = 0.043) ([Table 6]).
Table 6 Comparison of birth weight and Apgar score within multifetal pregnancy among the three study groups


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The mean Apgar score in twin and triplet gestations was significantly higher in the combination group than that in the progesterone and cerclage groups (F = 4.482, P = 0.013). Multiple comparisons showed that the difference in the Apgar score was not statistically significant between the progesterone and the cerclage groups (T = 0.061, P = 1.000), statistically significant between the combination and the cerclage groups (T = 1.369, P = 0.037), and statistically significant between the combination and the progesterone groups (T = 1.352, P = 0.048) ([Table 6]).

The number of neonates admitted to the NICU for twin and triplet gestations was significantly lower in the combination group than that in the progesterone and cerclage group (χ2 = 10.106, P = 0.006) ([Table 7] and [Figure 7]).
Figure 7 Percentage of neonatal intensive care unit admission within multifetal pregnancy among the three study groups.



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Table 7 Comparison of neonatal intensive care unit admission within multifetal pregnancy among the three study groups


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  Discussion Top


Until recently, prevention of PTB seemed to be an elusive goal. In the USA, the rate of PTB increased steadily from 9.4% in 1981 to a peak of 12.8% in 2006 [32]. Much of our clinical effort during this time involved tocolytic therapy, which proved to be generally ineffective in prolonging pregnancy or reducing the rate of neonatal complications [33]. Until recently, antenatal corticosteroid treatment was practically the only evidence-based treatment available in our arsenal to deal with the problem of PTB.

Three interventions have been proposed to treat patients with a sonographic short cervix:

  1. Vaginal administration of progesterone [8],[10] .
  2. Cervical cerclage for patients with a history of PTB [21],[24] .
  3. Vaginal pessary [34],[35].


Recently, a combination of vaginal progesterone and a pessary has been reported to be a successful method in reducing the rate of preterm delivery in twin gestations with a cervix of less than 25 mm [36].

A strength of the current study is that it is one of few studies involving the simultaneous use of vaginal progesterone as well as cervical cerclage. It is noteworthy that although the current study is a randomized prospective one, the few others [8],[12],[24],[27],[29],[36],[37],[38] that have investigated the use of both remedies were retrospective studies.

We found that vaginal progesterone and cervical cerclage were equally effective in reducing the risk of PTL in singleton pregnancy with previous spontaneous PTL and in improving the composite perinatal outcome (higher mean birth weight, higher mean Apgar score, lower rate of NICU admission).

Some women may still have PTL despite treatment with either vaginal progesterone or cervical cerclage alone; thus, we combined both methods in our study and found that the concurrent use of vaginal progesterone and cervical cerclage was significantly more effective in reducing the rate of PTL in singleton pregnancy with previous spontaneous PTL and a short cervical length less than 25 mm in mid trimester and in improving the composite perinatal morbidity and mortality (significantly higher mean birth weight, higher mean Apgar score, lower rate of NICU admission).

The use of either vaginal progesterone or cerclage in patients with a cervical length of less than 25 mm in the mid trimester, singleton gestation, and previous spontaneous PTB was associated with a significant reduction in the risk of PTB at less than 32 weeks of gestation [RR 0.47, 95% confidence interval (CI) 0.24-0.91, for vaginal progesterone, and RR 0.66, 95% CI 0.48-0.91, for cerclage] and composite perinatal morbidity and mortality (response rate (RR) 0.43, 95% CI 0.20-0.94, for vaginal progesterone, and RR 0.64, 95% CI 0.45-0.91, for cerclage) compared with placebo and no cerclage, respectively [37] . Infants whose mothers received vaginal progesterone had a significantly lower risk of composite neonatal morbidity and admission to NICU than infants whose mothers had received placebo [37] . Patients who were allocated to cerclage showed a statistically significant reduction in the risk of PTB at less than 37, less than 35, and less than 28 weeks of gestation and a birth weight of less than 1500 g compared with those who did not receive cerclage. Vaginal progesterone and cerclage are equally efficacious in reducing the risk of PTL in high-risk pregnancy (previous spontaneous PTB, short cervical length <25 mm in mid trimester) [37] . The indirect comparison of meta-analysis shows trends toward better outcomes with vaginal progesterone compared with cerclage RR more than 1.0, but these did not reach statistical significance because the 95% CIs overlap 1 [31] .

In our study, we found that vaginal progesterone alone or cervical cerclage alone was not effective in reducing the risk of PTL in twin or triplet gestations.

The concurrent use of vaginal progesterone and cervical cerclage was significantly effective in reducing the risk of PTL in twins and triplets pregnancy and was significantly associated with better perinatal outcomes (significantly higher mean birth weight, higher mean Apgar score, lower rate of NICU admission).

In 677 women with diamniotic twin gestation, administration of vaginal progesterone 200 mg pessaries starting at 20-24 weeks until 34 weeks were not associated with significant effects on incidences of PTL or perinatal complications compared with placebo [38] .

In 67 twin gestations, vaginal progesterone 100 mg suppositories daily between 24 and 34 weeks were associated with a significant reduction in incidences of PTB less than 37 weeks (51 vs. 79%, OR 3.48, 95% CI 1.16-10.46), but not less than 34 weeks (10 vs. 25%, OR 2.90, 95% CI 0.76-11.20) compared with placebo [9] .

In a meta-analysis including 52 twin gestations found to have a trans vaginal ultrasound (TVU) CL less than 25 mm at less than 24 weeks, administration of vaginal progesterone was associated with a similar incidence of PTB 33 weeks (30 vs. 45%, RR 0.70; 95% CI 0.34-1.44) and less than 35 weeks (52 vs. 62%, RR 0.91, 95% CI 0.57-1.46), but a significant reduction in composite neonatal morbidity and mortality (24 vs. 40%, RR 0.56, 95% CI 0.30-0.97) compared with placebo [12] . There is insufficient evidence to determine whether the concurrent use of progesterone and cerclage exerts an additive effect in reducing the risk of PTL in this group of women with previous PTL [39] .


  Conclusion Top


Either vaginal progesterone or cerclage is equally effective in preventing PTB in women with a high risk of PTL (singleton pregnancy, a sonographic short cervical length <25 mm in the mid trimester, and a history of previous spontaneous PTB) and in improving the composite perinatal morbidity and mortality. Selection of the optimal treatment needs to consider adverse events, cost, and patient/clinician preferences.

The combination of vaginal progesterone and cervical cerclage yielded statistically significantly better results in PTL prevention and in improving the composite perinatal morbidity and mortality (significantly higher mean birth weight, higher mean Apgar score, and lower rate of NICU admission).

The combination of vaginal progesterone and cervical cerclage was found to be significantly effective in reducing the risk of PTL in twins and triplets pregnancy (longer mean gestational age at delivery) and in improving the composite perinatal outcomes (significantly higher mean birth weight, higher mean Apgar score, and lower rate of NICU admission).


  Acknowledgements Top


Conflicts of interest

There are no conflicts of interest.

 
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    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7]



 

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Abstract
Introduction
Patients and methods
Results
Discussion
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Acknowledgements
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