Impact of Antenatal Care on Perinatal Outcomes in New South Wales, Australia: A Decade-Long Regional Perspective

Abstract

Low birth weight (LBW) and preterm birth are adverse perinatal outcomes that pose a significant risk to a child's healthy beginning. While antenatal care (ANC) is an established intervention for pregnancy care, little is understood about how the number and timing of ANC visits can impact these adverse health outcomes. This study aimed to examine the impact of the number and timing of ANC visits on LBW and preterm birth in a regional setting. A decade-long perinatal dataset related to singleton live births that took place in the Southern New South Wales Local Health District (SNSWLHD) was utilized. The outcomes of interest were LBW and preterm birth, and the exposure variables were based on the Australian pregnancy guidelines on the number and timing of ANC visits. A multivariable logistic regression was performed to measure the association between outcome and exposure while adjusting for potential confounders. A greater level of protection against LBW and preterm birth was observed among mothers who had an adequate number of visits, with early entry (first trimester) into ANC. The protective effect of an adequate number of ANC visits against LBW and preterm birth among mothers with late entry into ANC (third trimester) was found to be statistically non-significant.

Keywords: Australia; New South Wales; adverse pregnancy outcome; antenatal care; low birth weight; perinatal care; preterm birth.

Figure 1

Selection of the sample for the period of 2011–2020 in the Southern New South Wales Local Health District (SNSWLHD).

Figure 2

Impact of recommended number of antenatal care (ANC) visits on low birth weight (LBW) by the timing of the first visit in the Southern New South Wales Local Health District, determined by multivariate analysis, 2011–2020. **: p-value < 0.001; *: p-value <0.05; CI: confidence interval; aOR: adjusted odds ratio, adjusted for year of birth, hospital of birth, wealth quintile, maternal age, maternal Aboriginal status, maternal hypertension, maternal diabetes, tobacco smoking, newborn Aboriginal status, Apgar score, newborn sex, mode of birth, and preterm birth; number of cases included in multivariable analysis: 12,528.

Figure 3

Impact of recommended number of antenatal care (ANC) visits on preterm birth by the timing of the first visit in the Southern New South Wales Local Health District, determined by multivariate analysis, 2011–2020. **: p-value < 0.001; CI: confidence interval; aOR: adjusted odds ratio, adjusted for year of birth, hospital of birth, wealth quintile, maternal age, maternal Aboriginal status, maternal hypertension, maternal diabetes, tobacco smoking, newborn Aboriginal status, Apgar score, newborn sex, mode of birth, and birth weight; number of cases included in multivariable analysis: 125,284.