Related Experiment Video
Updated: Aug 17, 2026
Intranasal Immunization and Milk Collection in Studies of Maternal Immunization in New Zealand White Rabbits (Oryctolagus cuniculus)
Published on: July 31, 2021
Immunization Completion in Infants Born at Low Birth Weight
Matt Nestander1, Jay Dintaman2, Apryl Susi3
1Department of Pediatrics, Madigan Army Medical Center, Tacoma, Washington.
Insights
Low birth weight (LBW) infants have lower immunization completion rates. Ensuring consistent healthcare provider visits and well-child care can improve vaccination outcomes for these vulnerable infants.
Area of Science:
- Pediatrics
- Public Health
- Immunology
Background:
- Low birth weight (LBW) is linked to underimmunization.
- Previous research suggests factors like prematurity and illness mediate this association.
- Understanding LBW's direct impact on immunization is crucial.
Purpose of the Study:
- To determine the effect of LBW on immunization completion.
- To control for potential mediators like prematurity, neonatal illness, and healthcare utilization.
- To identify factors promoting immunization in LBW infants.
Main Methods:
- Retrospective cohort study of infants born 2008-2011 with military healthcare.
- Used ICD-9 codes to identify LBW, comorbidities, and healthcare visits.
- Logistic regression analyzed odds of immunization completion and well-child care.
Main Results:
- 85.7% of infants completed immunizations by age 2.
- LBW infants had significantly decreased odds of immunization completion (OR 0.88).
- Very LBW (OR 0.61) and extremely LBW (OR 0.45) showed greater deficits. Preterm birth, chronic lung disease, and inconsistent providers also reduced completion.
Conclusions:
- LBW remains a significant independent risk factor for immunization noncompletion, even with healthcare access.
- Consistent provider care and complete well-child visits are vital for improving immunization rates in LBW infants.
- Targeted interventions focusing on well-child care may enhance vaccine uptake in this population.
Background:
Low birth weight (LBW) has been associated with underimmunization. We sought to understand the effect of LBW on immunization completion after controlling for previously hypothesized mediators, including prematurity, neonatal illness, well-child care, non-well-child visits, and provider consistency.
Methods:
We formed a retrospective cohort of infants born between 2008 and 2011 with ≥2 years of military healthcare follow-up. International Classification of Diseases, Ninth Revision codes were used to identify LBW, preterm birth, neonatal illnesses, well-child visits, non-well-child visits, provider consistency, and parental rank in the inpatient and outpatient records. Immunization records were extracted from both records. Logistic regression determined the odds of immunization completion and well-child care completion (ie, having had ≥6 WCC visits by 15 months of age).
Results:
Of 135964 included infants, 116521 (85.7%) were completely immunized at the age of 2 years. In adjusted analysis, the odds of immunization completion were significantly decreased in infants born at LBW (odds ratio [OR], 0.88 [95% confidence interval (CI), 0.79-0.97]), very LBW (OR, 0.61 [95% CI, 0.48-0.77]), or extremely LBW (OR, 0.45 [95% CI, 0.33-0.63]) or at ≤32 weeks' gestation (OR, 0.76 [95% CI, 0.63-0.92]), infants with chronic lung disease (OR, 0.63 [95% CI, 0.45-0.88]), male infants (OR, 0.96 [95% CI, 0.93-0.99]), and infants who experienced decreased provider consistency (OR, 0.92 [95% CI, 0.91-0.92]). The rate of immunization completion increased with the overall number of healthcare visits (OR, 1.02 [95% CI, 1.02-1.02]) and complete well-child care (OR, 1.80 [95% CI, 1.75-1.86]). However, children born LBW or preterm were significantly less likely to have complete well-child care.
Conclusions:
After adjustment for preterm birth, comorbid neonatal conditions, and early childhood patterns of healthcare use, LBW was significantly associated with immunization noncompletion in a universal healthcare system. Provider consistency and well-child care seem important for increasing immunization completion in LBW infants.
Related Concept Videos
01:51Vaccinations
01:15Transcytosis of IgG
IgG molecules from a mother undergo transcytosis starting around 13 weeks of gestation. The amount of IgG transferred and entering the fetal blood circulation increases with...
01:31Active versus Passive Immunity
Active Immunity
Active immunity refers to the resistance one develops...
01:22Development of Immunocompetence
The initial cells that migrate from the fetal thymus settle within the skin and epithelial tissues lining the mouth, digestive tract, and in females, the uterus and vagina. These cells, including skin-based dendritic cells, serve as antigen-presenting cells, playing a key role in T cell activation.
Subsequent T...
01:25Immunodeficiency Diseases
There are three main causes of immunodeficiency disorders...
01:29Drug Dosing: Infants and Children