Late PretermEdit

Late preterm refers to infants born between 34 0/7 and 36 6/7 weeks of gestation. Although only modestly earlier than the traditional 37-week cutoff for term birth, babies in this window face higher risks of certain problems compared with those born at full term. These infants often look healthy at birth but may require observation and care in the neonatal intensive care unit or extended newborn follow-up to manage breathing difficulties, feeding challenges, temperature regulation, and jaundice. The late preterm period accounts for a substantial share of preterm births and occupies a central place in discussions about obstetric decisions, health care costs, and family outcomes. gestational age preterm birth

Late preterm infants commonly begin life with a scorecard that includes a higher likelihood of respiratory distress, apnea, and hypoglycemia, as well as a greater need for feeding support and longer hospital stays than term infants. Even when stabilized, they have higher rates of readmission in the first months of life and increased risk for temperature instability and dehydration. These risks highlight why clinicians monitor late preterm babies closely in the neonatal intensive care unit and plan for careful discharge and follow-up. respiratory distress syndrome hypoglycemia jaundice

Definition and scope

Definition: late preterm encompasses births at 34 0/7 through 36 6/7 weeks of gestation. This contrasts with term (approximately 39–40 weeks) and very preterm births (before 32 weeks). See gestational age for broader context.
Scope in care: management often involves vigilant observation after birth, evaluation for breathing and feeding adequacy, temperature control, and, when indicated, supportive therapies in the neonatal intensive care unit. Guidance on when to deliver or intervene combines fetal status, maternal health, and practical considerations about maternal-fetal stability. See antenatal corticosteroids for cases where preterm birth is anticipated, and elective induction of labor for discussion about scheduling births.

Epidemiology

Late preterm births occur across populations, with substantial variation by country, region, and health system. In many high-income countries, late preterm births make up a large share of all preterm births and are influenced by factors such as maternal health, access to prenatal care, and obstetric practices. Racial and ethnic disparities in preterm birth exist in several settings; in some systems, rates are higher among black populations compared with white populations, reflecting a complex mix of biology, health status, and social determinants. See racial disparities in preterm birth for related discussion. preterm birth

Causes and risk factors

A variety of maternal, fetal, and obstetric factors contribute to late preterm birth and the conditions that accompany it. Key risk factors include:

Maternal hypertension or preexisting diabetes, obesity, or other metabolic conditions. maternal health diabetes mellitus
Prior preterm birth or a history of spontaneous preterm labor.
Multiple gestation (twins, triplets) or placental problems.
Inadequate prenatal care or late presentation to obstetric care, along with stressors or infections during pregnancy.
Medical decisions around timing of delivery in high-risk situations, including suspected fetal compromise or maternal illness. See preterm birth and elective induction of labor for broader context.

Clinical features and neonatal course

Late preterm infants may be stable at birth but frequently require careful monitoring for some common issues:

Respiratory: a higher risk of respiratory distress or apnea compared with term infants; some may need supplemental oxygen or temporary support in the neonatal intensive care unit. respiratory distress syndrome
Feeding and energy: difficulties with feeding, slower weight gain, and a need for lactation support or specialized feeding plans. feeding difficulties
Temperature and hydration: greater risk of temperature instability and dehydration, requiring careful thermal management.
Jaundice and metabolic concerns: higher incidence of jaundice and potential hypoglycemia, necessitating monitoring and sometimes treatment.
Infections: increased vigilance for signs of sepsis or other infections, particularly in babies with other risk factors.

Management and care

Delivery timing decisions: when possible, avoiding non-medically indicated early deliveries before 39 weeks minimizes late preterm risk. Decisions depend on fetal and maternal status and are guided by clinical judgment and guidelines. See elective induction of labor and cesarean section for related discussions.
Antenatal interventions: in cases where preterm birth is anticipated, clinicians may consider antenatal corticosteroids to accelerate fetal lung maturity, though applicability varies by gestational age and risk profile.
Postnatal care: emphasis on careful feeding support, temperature control, and gradual transition from hospital to home with appropriate follow-up. Breastfeeding and skin-to-skin care can aid thermoregulation and feeding confidence. See breastfeeding for broader context.
Follow-up and outcomes: many late preterm babies do well with appropriate care, but some require longer hospital stays or early pediatric follow-up to monitor growth, development, and any late-emerging concerns.

Outcomes and prognosis

The prognosis for late preterm infants is generally favorable with modern neonatal care, but outcomes are modestly worse than those for term infants in several domains. Short-term risks include respiratory problems, feeding difficulties, and jaundice, with a greater likelihood of extended hospital stay and NICU readmission. Long-term considerations cover neurodevelopmental outcomes and school readiness, where some studies show a small but measurable increase in risk relative to term peers, particularly among babies with complications in the perinatal period. The absolute risks, however, remain relatively low for most late preterm babies who receive appropriate care. See neurodevelopment for related discussions.

Controversies and debates

Elective early delivery and health care costs: a core debate centers on how aggressively to limit non-medically indicated births before 39 weeks. Proponents of tighter guidelines argue that reducing late preterm births lowers NICU utilization, short- and long-term health care costs, and parental stress, while preserving patient safety. Critics contend that overly prescriptive rules can infringe on clinical judgment and parental choice, potentially prolonging pregnancy in cases where early delivery might be clinically warranted.
Equity and access: the debate often intersects with broader health policy concerns about access to prenatal care, social determinants of health, and how to address disparities in preterm birth rates. From a pragmatic perspective, improving maternal health and access to high-quality care can reduce late preterm births, but critics argue that policy measures should be targeted rather than punitive and should respect patient autonomy.
Woke criticisms and policy responses: supporters of a value-driven, evidence-based approach argue that focusing on clear risk data and cost-effective care yields better outcomes for families across communities, including black and white populations and other groups, without resorting to sweeping social policies that may have unintended consequences. Critics may frame such positions as insufficient attention to equity; defenders reply that responsible policy must balance access, cost, and clinical science, and that good outcomes come from better risk communication, patient education, and high-quality prenatal care rather than blanket mandates.