Health Technology Assessment Unit, National School of Public Health, Oswaldo Cruz Foundation, Brazilian Health Ministry, Rio de Janeiro, Brazil.
Trials. 2011 Nov 8;12:239. doi: 10.1186/1745-6215-12-239.
Bacterial vaginosis increases the risk of spontaneous preterm delivery at less than 34 weeks of gestation.
The purpose of this study was to evaluate the efficacy of the early administration of selected lactobacilli strains (probiotics) to pregnant women with asymptomatic bacterial vaginosis/intermediate-degree infections to prevent spontaneous premature delivery and associated neonatal morbidity.
METHODS/DESIGN: Asymptomatic pregnant women at less than 20 weeks of gestation, with no indication of elective preterm delivery, with a vaginal pH ≥ 4.5 and Nugent score > 3 were randomly assigned to the placebo or intervention group (oral administration of selected lactobacilli up to the 24th to 26th week of gestation). The randomisation was stratified for the history of premature delivery (HPD) and blocked. The allocation was concealed, and the participating health professionals and patients were blinded. The primary outcome was preterm delivery (<34 to <32 weeks), and the secondary outcomes were associated neonatal complications.
In total, 4,204 pregnant women were screened; 320 and 324 individuals were respectively randomly assigned to the placebo and intervention groups, and 62% finished the trial. None of the randomised patients were lost to follow-up. For the non-HPD stratum, the intent-to-treat relative risks of spontaneous premature birth at < 34 and < 37 weeks' gestation were 0.33 (0.03, 3.16) and 0.49 (0.17, 1.44), respectively, and they were non-significant (ns) with p = 0.31 and 0.14. The corresponding actual treatment figures were zero and 0.32 (0.09, 1.19), which were ns with p = 0.12 and 0.06. The intent-to-treat relative risk of spontaneous premature birth at < 37 weeks of gestation for the trial as a whole, including HPD and non-HPD participants, was 0.69 (0.26, 1.78), p = 0.30 (ns). The neonatal complications under evaluation occurred in only one infant (< 34 weeks; placebo group) who presented with respiratory distress syndrome and suspected early neonatal sepsis. The recorded adverse events were minor and relatively non-specific.
The efficacy of the tested probiotics to prevent preterm delivery among women without a history of preterm delivery was not determined because the study sample was insufficient to estimate statistically significant intent-to-treat effects; additional studies are needed to evaluate this intervention among these women.
Trial registration at NIH register: NCT00303082. Sources of funding: the Brazilian Health Ministry and the State of Rio de Janeiro Research Foundation.
细菌性阴道病会增加不到 34 周妊娠自发性早产的风险。
本研究旨在评估早期给予无症状细菌性阴道病/中度感染孕妇选定的乳酸菌株（益生菌）以预防自发性早产和相关新生儿发病率的疗效。
方法/设计：不到 20 周妊娠、无选择性早产指征、阴道 pH 值≥4.5 和 Nugent 评分>3 的无症状孕妇被随机分配至安慰剂或干预组（口服选定的乳酸菌直至 24 至 26 周妊娠）。随机分为早产史（HPD）分层和分组。随机分配是隐蔽的，参与的卫生专业人员和患者是盲法的。主要结局是早产（<34 至<32 周），次要结局是相关新生儿并发症。
共有 4204 名孕妇接受了筛查；320 名和 324 名孕妇分别被随机分配至安慰剂和干预组，62%的孕妇完成了试验。没有随机患者失访。对于非 HPD 分层，自发性早产的意向治疗相对风险分别为<34 周和<37 周妊娠时为 0.33（0.03，3.16）和 0.49（0.17，1.44），均无统计学意义（ns），p=0.31 和 0.14。相应的实际治疗数据分别为零和 0.32（0.09，1.19），p=0.12 和 0.06，均无统计学意义。整个试验（包括 HPD 和非 HPD 参与者）自发性早产<37 周的意向治疗相对风险为 0.69（0.26，1.78），p=0.30（ns）。仅在一名婴儿（<34 周；安慰剂组）中出现呼吸窘迫综合征和疑似新生儿早期败血症的情况下发生了评估中的新生儿并发症。记录的不良事件是轻微的，相对非特异性的。
由于研究样本不足以估计统计学上有意义的意向治疗效果，因此无法确定该试验益生菌预防无早产史孕妇早产的疗效；需要进一步研究来评估这种干预措施在这些女性中的效果。
在美国国立卫生研究院注册处注册：NCT00303082。资金来源：巴西卫生部和里约热内卢州研究基金会。
