Last reviewed: 30 Aug 2023
Last updated: 06 Jul 2023
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
More key diagnostic factors
Other diagnostic factors
- infant birth weight (appropriate for gestational age infants)
Other diagnostic factors
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
- maternal age ≥35 years
- nonwhite race
More risk factors
Diagnostic investigations
1st investigations to order
- fetal biometry during prenatal period
More 1st investigations to order
Investigations to consider
- fundoscopy
More investigations to consider
Treatment algorithm
ACUTE
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.
Acknowledgements
Dr Mohan Pammi 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.
Differentials
- Small for gestational age (SGA)
- Intrauterine growth restriction (IUGR)
More DifferentialsGuidelines
- International consensus on cardiopulmonary resuscitation and emergency cardiovascular care science with treatment recommendations: summary from the basic life support; advanced life support; pediatric life support; neonatal life support; education, implementation, and teams; and first aid task forces
- Recommendations for care of the preterm or low-birth-weight infant
More GuidelinesPatient leaflets
Premature labor
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