概述

当在怀孕第 20 周和第 37 周之间有规律的宫缩导致宫颈扩张时,就会发生未足月分娩。

未足月分娩可导致早产。早产发生得越早,对婴儿的健康风险就越大。许多早产婴儿(早产儿)需要在新生儿重症监护室进行特殊护理。早产儿也可能有长期的精神和身体残障。

未足月分娩的具体原因往往不清楚。某些风险因素可能增加发生未足月分娩的几率,但未足月分娩也可能发生在没有已知风险因素的孕妇身上。

症状

未足月分娩的体征和症状包括:

  • 经常或者频繁出现腹部紧绷感(反复收缩)
  • 持续的腰部钝痛
  • 盆腔或下腹部压迫感
  • 轻微的腹部绞痛
  • 阴道点滴出血或少量出血
  • 胎膜早破,即胎膜破裂或撕裂后涌出或持续滴出液体
  • 阴道分泌物类型发生变化,即出现水性、黏液样或血性分泌物

何时就诊

如果您出现了这些体征或症状,或是对自己的感受有所担心,请立即咨询您的医疗护理提供者。病情要紧,不要怕麻烦。如果只是虚惊一场,大家都会很高兴。

风险因素

未足月分娩会影响任何怀孕。然而,许多因素与增加未足月分娩的风险有关,包括:

  • 以前有过未足月分娩或早产,尤其是最近一次怀孕或多次怀孕出现这些情况
  • 怀有双胞胎、三胞胎或其他多胞胎
  • 宫颈缩短
  • 子宫或胎盘问题
  • 吸烟或使用非法药物
  • 某些感染,尤其是羊水和下生殖道感染
  • 一些慢性病症,如高血压、糖尿病、自身免疫病和抑郁症
  • 遭遇让人倍感压力的生活事件(例如所爱之人去世)
  • 羊水过多
  • 妊娠期阴道出血
  • 胎儿出生缺陷
  • 怀孕间隔少于 12 个月或超过 59 个月
  • 母亲的年龄,太小和太大
  • 黑人、非西裔和族裔

并发症

未足月分娩的并发症包括分娩早产儿。这可能给您的宝宝带来很多健康问题,比如低出生体重、呼吸困难、器官发育不全和视力问题。早产儿童患脑瘫、学习障碍和行为问题的风险也更高。

预防

您可能无法防止未足月分娩,但您可以做很多事情来促进健康的足月妊娠。例如:

  • 定期产检。产前检查有助于医护人员监测您和婴儿的健康。告知让您担忧的体征或症状。如果您有未足月分娩史或出现未足月分娩的体征或症状,您可能需要在怀孕期间更频繁地看医护人员。
  • 健康饮食。健康怀孕通常与良好的营养有关。此外,一些研究表明,多不饱和脂肪酸(PUFA)含量高的饮食与较低的早产风险有关。坚果、种子、鱼和种子油富含 PUFA
  • 避免使用有风险药物。如果您抽烟,请戒烟。向医护人员咨询戒烟计划。不要使用违禁药物。
  • 考虑怀孕间隔。一些研究表明,怀孕间隔少于 6 个月或超过 59 个月可增加早产风险。考虑与您的医护人员讨论怀孕间隔。
  • 谨慎使用辅助生殖技术(ART)。如果您计划通过 ART 怀孕,请考虑要植入多少个胚胎。多胎妊娠有较高的未足月分娩风险。
  • 管理慢性疾病。糖尿病、高血压和肥胖症等疾病会增加未足月分娩的风险。与医护人员合作,控制慢性疾病。

如果医护人员确定您未足月分娩的风险增加,他或她可能会建议采取额外措施来降低风险。

Jan. 13, 2022
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