Women's acceptance of a preterm birth prevention program

A major modification in French national perinatal policy was proposed in 1970. Its primary aim was to reduce preterm births, and a specific program has been progressively applied to all pregnant women in France since 1971. Because the policy was introduced at a national level, it was possible to use a district hospital in Haguenau (northeastern France) as an observation site for measuring the effects of the change. A longitudinal study was begun in 1971 and continued for 12 years, during which time a total of 16,004 singleton pregnancies were followed. This article focuses on acceptance by the pregnant women in Haguenau in response to the new prenatal care proposals. A major reduction in preterm births is demonstrated, and the relationship between acceptance and observed changes in preterm birth is discussed. Certain time-related patterns were observed: it took time for the policy modification to be measurable; while the outcomes showed general improvement, results were closely related to the patient's social status; there were significant time-lag differences between social class groups with regard to acceptance of specific interventions.     

Elective cervical cerclage for prevention of preterm birth: a systematic review

BACKGROUND: Elective cervical cerclage has been purported to prevent spontaneous preterm birth. We present a systematic review to determine the effectiveness of cervical cerclage in preventing spontaneous preterm birth before 34 weeks' gestation. METHODS: Searches were conducted in MEDLINE, EMBASE, Cochrane Library, and Science Citation Index to identify randomized trials published between 1966 and 2002. All randomized trials that evaluated the effectiveness of elective cerclage compared with no cerclage in women who were at risk of preterm birth before 34 weeks' gestation were included for analysis. Quality assessment and data extraction were performed in duplicate. RESULTS: There were seven relevant trials, comprising 2354 women. Meta-analysis was inappropriate because of large differences in the quality of the studies. However, in the largest single trial of good quality, cerclage was shown to prevent birth before 34 weeks' gestation. In this single study the reported number to be treated to prevent one additional preterm birth before 34 weeks was 24 women (95% CI: 10-61). The results of other trials were consistent with the finding of the largest trial. Data on complications were sparse and inconclusive. CONCLUSION: Our systematic review shows that elective cervical cerclage has a significant effect in preventing spontaneous preterm birth before 34 weeks' gestation. Further research should focus on identification and quantification of possible complications, and of risk factors and tests that identify high-risk women who would benefit most from cerclage.     

Evaluation of risk scoring in a preterm birth prevention study of indigent patients

A total of 4591 indigent patients were scored for risk of preterm labor and birth by the Creasy et al. scoring system and delivered at greater than or equal to 20 weeks' gestation. Of 462 preterm deliveries (less than 37 weeks), only 39.6% were contributed by the 18.1% of patients who scored at high risk (score greater than or equal to 10). Of the 44 risk factors in the scoring system, 25 were not statistically significant by univariate chi 2 analysis. The spontaneous preterm birth rate was 8.0%. The positive predictive value of the Creasy et al. system was 18.3%. With multiple logistic analyses we excluded infrequent risk factors and identified five factors that remained significant (prepregnancy weight less than 45.5 kg, black race, single marital status, one preterm labor and delivery, preterm labor, and delivery greater than or equal to 2). With these five risk factors we created an equation that allowed identification of 12% of patients at high risk of preterm delivery with a positive predictive value of 21.9%. Because of the importance of previous preterm delivery, risk scoring of primigravid patients is of limited value.     

Universal cervical length screening for preterm birth prevention in the United States*

Objective: To evaluate the incidence of implementation of universal cervical length (CL) screening for preterm birth (PTB) prevention among institutions with Maternal–Fetal Medicine (MFM) fellowship training in the United states.

Methods: In January 2015, we conducted a national survey of institutions with MFM Fellowship Programs regarding implementation of universal CL screening, defined as CL screening of women with singleton gestations without a prior spontaneous PTB. We identified whether a transabdominal ultrasound (TAU) or transvaginal ultrasound (TVU) was used for screening. Results were compared by geographical regions.

Results: We identified 78 MFM fellowship programs nationwide, of which 100% responded to the survey, provided by MFM fellows (86%) and MFM division directors (14%). In January 2015, 53 programs (68%) had implemented a CL screening program, with 25 programs (32%) using TVU while the rest (36%) used TAU for CL screening. The 16 programs in the Midwest had the highest percent of CL screening (15 programs, 94%), with the highest use of TVU (8 programs 50%). The 24 programs in the South had the lowest percent of CL screening (14 programs, 58%) (odds ratio [OR]: 0.52, 95% confidence interval [CI]: 0.19–1.46) and the lowest use of TVU (3 programs,12.5%) (OR: 0.22, 95% CI: 0.05–0.78) compared to rest of US).

Conclusion: Universal CL screening has been implemented by over two-thirds of institutions with MFM Fellowship Programs, as of January 2015. Of these programs, about half screen by TAU and half by TVU.     

Comparison of two cervical cerclages for the prevention of preterm birth and neonatal complications

Objective: To investigate the outcomes of singleton pregnant women with cervical insufficiency undergoing two different cervical cerclages.

Methods: This is a retrospective cohort study of women who underwent a history- or ultrasound-indicated cerclage (either Shirodkar or McDonald) at a tertiary referral center from 2002 to 2014. Outcome parameters (delivery age, postoperative cervical length, preterm premature rupture of membranes, preterm delivery rate and neonatal complications) were compared between the two cerclage procedures. Multivariate logistic regression analysis was applied to control for significant variables of preterm birth. Kaplan–Meier survival analysis was used to demonstrate delivery age to percentage of term delivery by cerclage type.

Results: Ninety-four cases were initially included. After excluding cases not meeting the study criteria, 60 pregnancies (Shirodkar 36 and McDonald 24) were recruited for analysis. The mean delivery age in the Shirodkar group was more advanced than that in the McDonald group (37.1?±?3.3 versus 34.8?±?4.9 weeks, p?=?0.039). There were significantly fewer deliveries <37 gestational weeks in the Shirodkar group than in the McDonald group (30.6% versus 58.3%, p?=?0.033) but no significant differences in deliveries <28, 32 and 34 gestational weeks. No significant differences were found in neonatal complications except for respiratory distress syndrome (5.6% in Shirodkar versus 29.2% in McDonald, p?=?0.023).

Conclusion: In the setting of history-indicated or ultrasound-indicated cerclage, Shirodkar was superior to McDonald in the prevention of late preterm birth and neonatal respiratory distress syndrome.     

Progesterone for preterm birth prevention

Preterm birth—delivery before 37 weeks of gestation—is the second leading cause of infant mortality in the United States after congenital malformations. Spontaneous preterm birth, due to either preterm labor or preterm premature membrane rupture, encompasses approximately 75% of all preterm births, almost 400,000 births per year. Since the 1960s, different formulations of progesterone have been investigated for preterm birth prevention. This article addresses the use of progesterone for the prevention of preterm birth, including selection of candidates for progesterone, pharmacokinetics, dosing, and formulations. This article aims to provide a practical guide for using progesterone in clinical practice.     

Cervical cerclage in the prevention of preterm birth

Cervical cerclage has been used in the management of cervical insufficiency for several decades, yet the indications are uncertain and benefits marginal. It remains a controversial intervention. The diagnosis of cervical insufficiency is traditionally based on a history of recurrent second trimester miscarriages, or very preterm delivery whereby the cervix is unable to retain the pregnancy until term. Cervical cerclage has been the subject of many observational and randomised controlled trials. This article reviews the literature regarding the effectiveness of elective or emergency transvaginal cerclage and transabdominal cerclage.     

Effect of partial compliance on the prevention of recurrent preterm birth in women receiving weekly 17 alpha-hydroxyprogesterone caproate injections

Purpose: To analyze the effect of partial compliance on preterm birth (PTB) prevention among women with previous PTB and receiving 17 alpha-hydroxyprogesterone caproate (17-OHPC).

Study Design: This is a secondary analysis of a multicenter trial for the prevention of recurrent PTB. Women with prior PTB were randomly assigned between 15 0/7 and 20 3/7 weeks to weekly injections of either 17-OHPC or placebo. Full 100% compliance (group 1) was compared to 40-80% (group 2). Recurrent PTB rates and odds ratios were calculated. Student's t, Chi-square, Wilcoxon Rank-Sum, multivariate logistic regression and Breslow-Day tests were used.

Results: Group 1 included 370 women versus 35 in group 2. In each group, the PTB rate was significantly reduced in pregnancies receiving 17-OHPC compared to placebo. The adjusted odds ratio for PTB rate in group 1 was 0.48 (95% CI 0.31–0.75) versus 0.18 (95% CI 0.04–0.92) in group 2. Comparing the homogeneity of both odds ratios, the rates of recurrent PTB prevention in both groups were not statistically different (Breslow–Day test; p=?.15).

Conclusion: A compliance rate of 40–80% did not significantly reduce 17-OHPC’s efficacy. If confirmed, our findings could lead to a dramatic decrease in costs related to prevention of recurrent PTB.     

Utilization of progesterone and cervical length screening for prevention of recurrent preterm birth

Abstract

Objective: To assess utilization of progesterone and cervical length (CL) screening among women with prior spontaneous preterm birth (sPTB).

Methods: This is a retrospective cohort study of women with prior sPTB. Primary outcomes were the use of progesterone and CL screening. Secondary outcomes were reasons for failure to utilize interventions and factors associated with use of recommended interventions.

Results: 180 women had a prior sPTB. Of 171 women eligible for progesterone, 125 (74%) utilized it. Women who utilized progesterone were more likely to have a prior sPTB <28 weeks (50% vs 26%, OR 2.54 (1.18–5.42) p?=?.006) and a higher number of prior sPTB (1.5?±?0.9 vs 1.2?±?0.5, p?=?.02), and less likely to have a prior full term delivery (54% vs 72%, OR 0.47 (0.22–0.99), p?=?.04). Of 176 women eligible for CL screening, 157 (89%) utilized it. Women who utilized CL screening were less likely to have a prior full term delivery (59% vs 84%, OR 0.27 (0.07–0.95, p?=?.01)). The most frequent reason for lack of progesterone and CL screening was patient declining.

Conclusion: Most women with prior sPTB received progesterone and CL screening. Those at highest risk for PTB based on obstetric history are more likely to utilize recommended interventions.     

Shirodkar versus McDonald cerclage for the prevention of preterm birth in women with short cervical length

The efficacy of Shirodkar cerclage was compared with that of the McDonald procedure for the prevention of preterm birth (PTB) in women with a short cervix. Secondary analysis using data from all published randomized trials including women with a short cervical length (CL) was performed comparing the use of Shirodkar versus McDonald sutures. Analysis was limited to singletons with short CL on transvaginal ultrasound. The primary outcome measure was PTB < 33 weeks. Statistical analysis was performed using bivariate and multivariable techniques. From 607 women randomly assigned in the study, 277 met our inclusion criteria; 127 received Shirodkar and 150 women received McDonald sutures. The mean ( +/- standard deviation) gestational age at delivery was 35.0 +/- 5.3 versus 36.3 +/- 4.7 for the Shirodkar versus McDonald groups, respectively ( p< 0.02). PTB < 33 weeks was seen in 61 (22%) of 277 women; 26 (20%) of 127 in the Shirodkar and 35 (23%) of 150 in the McDonald groups, respectively (odds ratio [OR], 0.85; 95% confidence interval [CI], 0.5 to 1.6). On adjusting for confounders using logistic regression modeling, no significant difference in PTB < 33 weeks was found between the two groups (OR, 0.55; 95% CI, 0.2 to 1.3). In women with short cervical length randomly assigned to receiving cerclage, no significant difference in prevention of PTB was observed using Shirodkar or McDonald's procedures.     

Progestin treatment for the prevention of preterm birth

Progestin supplementation appears to be a promising approach to both preventing initiation of preterm labor and treating it once it is already established, given the role of progesterone in maintaining pregnancy, as well as support from basic and clinical research. Progesterone and 17α-hydroxyprogesterone acetate slow the process of cervical ripening, and this is the rationale for prophylactic long-term progestin supplementation mostly studied so far. However, progesterone (but not 17α-hydroxyprogesterone acetate) also inhibits myometrial activity even after the cervix has already ripened. Moreover, these effects depend greatly on the vehicle used and the route of administration. Understanding different mechanisms of action, as well as the importance of progestin formulation, vehicle and route of administration, is the key to finding the optimal progestin treatment for prevention of preterm birth.     

Progesterone supplementation and the prevention of preterm birth

Preterm birth is currently the most important problem in maternal-child health in the United States and possibly throughout the world. It complicates one in eight US deliveries, and accounts for over 85% of all perinatal morbidity and mortality. Although survival of preterm infants has increased steadily over the past four decades-due in large part to the use of antenatal corticosteroids, improvements in neonatal resuscitation, and the introduction of neonatal intensive care units-efforts to prevent preterm birth have been largely unsuccessful. On February 3, 2011, the US Food and Drug Administration (FDA) approved the use of progesterone supplementation (hydroxyprogesterone caproate) during pregnancy to reduce the risk of recurrent preterm birth in women with a history of at least one prior spontaneous preterm delivery. This is the first time that the FDA has approved a medication for the prevention of preterm birth, and represents the first approval of a drug specifically for use in pregnancy in almost 15 years. This article reviews the evidence behind the use of progesterone for the prevention of preterm birth, and provides guidelines for the use of progesterone supplementation in clinical practice. A number of areas of ongoing controversy are addressed, including the optimal formulation and route of administration, the safety of progesterone supplementation in pregnancy, and its proposed mode of action.     

宫颈环扎术在早产治疗中的应用

目的评估治疗性宫颈环扎术及预防性宫颈环扎术的效果。方法选择2003年1月至2006年3月北京大学第三医院的34周前的早产临产及宫颈机能不全患者,早产临产患者采取紧急宫颈环扎术联合宫缩抑制剂或者单纯使用宫缩抑制剂治疗。宫颈机能不全患者采取预防性宫颈环扎术、紧急环扎术以及非环扎保守治疗。对治疗结局进行统计学分析。结果在早产临产组,紧急宫颈环扎联合宫缩抑制剂（硫酸镁）来治疗早产,平均保胎天数45.00 d,较单纯用宫缩抑制剂硫酸镁抑制宫缩的34例患者保胎天数[中位数为1（0.75-16）d]明显延长,34、37周后分娩率分别为66.7%（26/39）、30.8%（12/39）,明显增加。宫颈机能不全患者预防性环扎及治疗性环扎均较非环扎组保胎天数延长,增加32、34周后的分娩率（P〈0.05）,但治疗性环扎可降低早产率（P=0.02）。结论观察资料结果显示早产临产患者硫酸镁联合宫颈环扎治疗早产效果更佳,增加34周以上的分娩率,降低早产率;预防性环扎不能降低37周前早产率,但能增加32、34周后分娩率,延长保胎天数;治疗性环扎可降低37周前早产率。     

The Alabama preterm birth prevention project

A preterm birth prevention program consisting of risk scoring, intensive weekly observation including cervical examinations, and detailed education about preterm labor signs and symptoms was tested in a predominantly black, indigent population. One thousand high-risk women were randomized to treatment or control groups. Although more preterm labor was diagnosed and treated in the treatment group, there were no significant differences between the groups with respect to mean birth weight or gestational age, spontaneous preterm delivery rates, or low or very low birth weight rates. The rates of respiratory distress syndrome and fetal and neonatal mortality, although greater in the treatment group, were not statistically different. However, the treatment-group infants had significantly more intracranial hemorrhages and spent more days on ventilators. At this institution, the preterm birth prevention program was not effective.