Charles E. Denk, Ph D, Maternal and Child Health Epidemiology, New Jersey Department of Health and Senior Services, P.O. Box 364, Trenton, NJ 08625-0364, 609-292-5656, Charles.Denk@doh.state.nj.us and Lakota K. Kruse, MD, MPH, Division of Family Health Services, New Jersey Department of Health and Senior Services, P O Box 364, Trenton, NJ 08625.

Background: In prior research the authors found that one-quarter of New Jersey women with adequate prenatal care utilization during their first pregnancies experience lower utilization during second pregnancies. Second pregnancies with timely initiation but fewer than the standard number of visits (intermediate level of utilization) exhibit slightly lower rates of low birth weight and preterm delivery than pregnancies with standard utilization. This sorting of lower-risk pregnancies into less intensive utilization may bias evaluation of the impact of prenatal care. Methodology: Electronic birth certificates in New Jersey from 1996 to 2001 were probabilistically linked for a cohort of 76,127 mothers. Kotelchuck’s Adequacy of Prenatal Care Utilization Index was used to assess utilization in the first two pregnancies. Logistic regression identified factors that predict prenatal care utilization, low birth weight and preterm delivery. Results: Sociodemographic attributes are strong predictors of individual decline from adequate to inadequate prenatal care, but not for declines to intermediate utilization. Intermediate utilization was more likely in the absence of medical risk factors and prior adverse outcomes. When medical risk indicators were included in the models for low birthweight and preterm delivery, there was no differential between adequate and intermediate prenatal care. Conclusions: Less intensive prenatal care utilization in the second pregnancy often reflects objectively lower medical risk. Public Health Implications: A WHO review suggests that “standard” prenatal care is in many cases over- intensive (Carroli, et al. Lancet 2001;357:1565-70). Population surveillance of appropriate prenatal care utilization depends on accurate assessment of risks due to under-utilization.

Learning Objectives:

• 1. Identify criteria for assessing adequacy of prenatal care utilization.
• 2. Articulate risk factors for under-utilization of prenatal care, and discuss how these factors are better understood using longitudinal research designs.

Keywords: Prenatal Care,

Presenting author's disclosure statement:
I do not have any significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.