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Parto prematuro

Last reviewed: 29 Jun 2025
Last updated: 19 Mar 2025

Summary

Definition

History and exam

Key diagnostic factors

  • presença de fatores de risco
  • contrações uterinas
  • ruptura prematura de membranas
  • dilatação cervical avançada
  • comprimento cervical <2 cm
Full details

Other diagnostic factors

  • frequência cardíaca fetal ou materna elevada
  • dor na parte inferior do abdome ou dorsalgia inespecífica
  • febre
  • sangramento vaginal
Full details

Risk factors

  • parto prematuro prévio
  • trauma cervical prévio
  • aborto induzido prévio
  • infecções maternas
  • gestações multifetais
  • comprimento cervical curto
  • exame de fibronectina fetal positivo
  • ruptura prematura de membranas
  • anormalidades fetais
  • tabagismo
  • índice de massa corporal (IMC) <19 kg/m²
  • fatores sociais e etnia
  • tratamento de fertilidade
  • polidrâmnio
  • violência doméstica
  • higiene dental insuficiente
  • parto cesáreo em estágio tardio
Full details

Diagnostic investigations

1st investigations to order

  • cardiotocografia sem estresse
  • tocografia
  • ultrassonografia transvaginal do colo uterino
  • exame de swab cérvico-vaginal para fibronectina fetal
  • Hemograma completo
  • proteína C-reativa
  • tira reagente para exame de urina
  • microscopia de urina, cultura e sensibilidade
  • exame de swab vaginal/retal alto
Full details

Investigations to consider

  • microscopia do fluido vaginal
  • exame de sangue de Kleihauer
  • exame toxicológico da urina
  • teste de proteína de ligação do fator de crescimento semelhante à insulina (IGFBP-1)
  • alfa-1 microglobulina placentária (PAMG-1)
Full details

Treatment algorithm

ACUTE

ameaça de parto pré-termo (APPT)

ruptura prematura de membranas

alto risco de parto iminente sem ruptura prematura de membranas

Contributors

Authors

Andrew H. Shennan, MD, FRCOG

Professor of Obstetrics

King's College London

London

UK

Disclosures

AHS has given talks for Hologic, the manufacturer of fetal fibronectin, and has received funds to his institute for research. AHS is an author of several references cited in this topic.

Joanna C. Girling, MA, MRCP, FRCOG

Consultant in Obstetrics and Gynaecology

West Middlesex University Hospital

London

UK

Disclosures

JCG declares that she has no competing interests.

Peer reviewers

Jo Trinder, MD

Consultant Obstetrician and Gynaecologist

St Michael's Maternity Wing

Bristol Royal Infirmary

Bristol

UK

Disclosures

JT has accepted honoraria for speaking to groups of midwives and doctors about miscarriage management.

Kirsty Dundas, MBChB, DCH, FRCOG

Consultant Obstetrician and Gynaecologist

Royal Infirmary of Edinburgh

Honorary Senior Lecturer

University of Edinburgh

Edinburgh

UK

Disclosures

KD declares that she has no competing interests.

Deidre Lyell, MD

Assistant Professor of Maternal-Fetal Medicine

Stanford University

Stanford

CA

Disclosures

DL declares that she has no competing interests.

References

Our in-house evidence and editorial teams collaborate with international expert contributors and peer reviewers to ensure that we provide access to the most clinically relevant information possible.

Key articles

National Institute for Health and Care Excellence. Preterm labour and birth. Jun 2022 [internet publication].Full text

Shennan AH, Story L, Royal College of Obstetricians, Gynaecologists. Cervical cerclage: green-top guideline no. 75. BJOG. 2022 Jun;129(7):1178-210.Full text  Abstract

EPPPIC Group. Evaluating Progestogens for Preventing Preterm birth International Collaborative (EPPPIC): meta-analysis of individual participant data from randomised controlled trials. Lancet. 2021 Mar 27;397(10280):1183-94.Full text  Abstract

Royal College of Obstetricians and Gynaecologists. Care of women presenting with suspected preterm prelabour rupture of membranes from 24+0 weeks of gestation. Green-top guideline no. 73. Jun 2019 [internet publication].Full text

American College of Obstetricians and Gynecologists' Committee on Committee Opinion-Obstetrics. ACOG committee opinion no. 713: antenatal corticosteroid therapy for fetal maturation. Obstet Gynecol. 2017 Aug;130(2):e102-9.Full text  Abstract

Reference articles

A full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice.
  • Differentials

    • Descolamento da placenta
    • Infecção do trato urinário (ITU)
    • Cisto ovariano
    More Differentials
  • Guidelines

    • Twin and triplet pregnancy
    • Cervical cerclage (Green-top guideline no. 75)
    More Guidelines
  • Patient information

    Parto prematuro

    More Patient information
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