Summary
Definition
History and exam
Key diagnostic factors
- maternal last menstrual period (LMP)
- distance from the maternal superior pubis to the uterine fundus
- infant physical maturity score
- infant neuromuscular maturity score
- combined physical/neuromuscular score <10: gestational age <28 weeks
- combined physical/neuromuscular score 11 to 19: gestational age 29 to 31 weeks
- combined physical/neuromuscular score 20 to 24: gestational age 32 to 33 weeks
- combined physical/neuromuscular score 25 to 33: gestational age 34 to 36 weeks
Other diagnostic factors
- infant birth weight (appropriate for gestational age infants)
Risk factors
- intrauterine infection
- preterm premature rupture of membranes (PPROM)
- pre-eclampsia/pregnancy-induced hypertension
- placental abruption/antepartum hemorrhage
- abnormal amniotic fluid volume
- severe bacterial vaginosis
- multiple gestation
- previous preterm birth
- fetal abnormality
- cervical incompetence/uterine abnormality
- gestational diabetes
- maternal surgery during pregnancy
- chronic maternal illness
- short interpregnancy time interval
- drug use (tobacco, cocaine, heroin)
- maternal pregnancy body mass index <19 or >35
- stress/depression
- extremes of maternal age
- nonwhite race
Diagnostic tests
1st tests to order
- fetal biometry during prenatal period
Treatment algorithm
gestational age <28 weeks
gestational age 28 to 31 weeks
gestational age 32 to 33 weeks
gestational age 34 to 36 weeks
Contributors
Authors
Mohan Pammi, MD, PhD
Professor of Pediatrics
Section of Neonatology and Department of Pediatrics
Baylor College of Medicine
Houston
TX
Disclosures
MP declares that he has no competing interests.
Kushal Bhakta, MD
Associate Professor
Neonatal Intensive Care Unit
Children’s Hospital of Orange County
Orange County
CA
Disclosures
KB declares that he has no competing interests.
Acknowledgements
Dr Mohan Pammi and Dr Kushal Bhakta would like to gratefully acknowledge Dr Stephen Welty and Dr James L. Wynn, previous contributors to this topic.
Disclosures
SW and JLW declare that they have no competing interests.
Peer reviewers
Isaac Babarinsa, MSc, MRCOG
Consultant Obstetrician and Gynaecologist
Gloucestershire Royal Hospital
Gloucester
UK
Disclosures
IB declares that he has no competing interests.
Peer reviewer acknowledgements
BMJ Best Practice topics are updated on a rolling basis in line with developments in evidence and guidance. The peer reviewers listed here have reviewed the content at least once during the history of the topic.
Disclosures
Peer reviewer affiliations and disclosures pertain to the time of the review.
References
Key articles
American Heart Association. AHA guidelines for CPR and emergency cardiovascular care. Part 5: neonatal resuscitation. 2020 [internet publication].Full text
Ballard JL, Khoury JC, Wedig K, et al. New Ballard Score, expanded to include extremely premature infants. J Pediatr. 1991 Sep;119(3):417-23. Abstract
Ng EH, Shah V. Guidelines for surfactant replacement therapy in neonates. Paediatr Child Health. 2021 Feb;26(1):35-49.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
- Small for gestational age (SGA)
- Intrauterine growth restriction (IUGR)
More DifferentialsGuidelines
- Neonatal infection: antibiotics for prevention and treatment
- American Heart Association and American Academy of Pediatrics focused update on neonatal resuscitation
More GuidelinesPatient information
Premature labor
More Patient information
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