This report examines the percentage of low birth weight babies born by Vermont resident mothers (regardless of the place of birth) statewide and at the county-level by year.

Low birth weight babies (weighing less than 2,500 grams/5.5 pounds) are more likely than babies with normal weight to have health problems as a newborn. They also have a higher risk of chronic health conditions later in life, like diabetes, heart disease, high blood pressure, and obesity. Low birth weight babies are at a greater risk for delays or disruptions in development and are associated with early delivery, mothers with chronic health conditions, not gaining enough weight in pregnancy, and problems with the placenta. 

Low birth weight data used in this report are from the Vermont Department of Health (VDH) Vital Statistics System. Vermont’s vital records (data concerning births, deaths, fetal deaths, marriages, civil unions, divorces, and dissolutions) are collected according to state and federal laws and stored in VDH’s Vital Statistics System. When a birth occurs in the state, the physician, midwife, or other birth attendant is required by law to complete a birth certificate and file it with the town clerk in the town of birth within 5 days. For hospital births, medical records staff usually complete the birth certificate. The completed birth certificate is recorded and filed in the town where the birth took place, and a certified copy is sent to VDH for incorporation in the state’s Vital Statistics System. Data are then sent to the National Vital Statistics System (NVSS), the Federal compilation of each state’s vital records data across the county, where public access is provided to statistical information from birth certificates.

Birth data in this report are Vermont resident births, regardless of whether the birth occured in or outside of Vermont. Low birth weight babies were defined as those weighing less than 2,500 grams (5.5 pounds). State-level data were aggregated by year while county-level data were averaged by discrete three-year periods to account for data that may fluctuate greatly from year to year, thus maximizing reliability.

Values between 1 and 10 (inclusive) were suppressed/removed for a given geography and replaced with the value ‘-999.’ Secondary suppression occurred in instances where a data element could be used to calculate a related value that was suppressed (e.g., when a numerator was suppressed for a given percentage, the denominator was also suppressed to prevent reverse calculation of the numerator). The suppression rules were enforced to prevent the identification of individuals in an effort to preserve privacy and confidentiality.

Low birth weight percentages were calculated using the following formula:

([Low Birth Weight Count for the Year] / [Live Birth Count with Birth Weight Data for the Year]) * 100

Average low birth weight percentages were calculated using the following formula:

([Average Low Birth Weight Count during the Three-Year Period] / [Average Live Birth Count with Birth Weight Data during the Three-Year Period]) * 100

Average counts and percentages used for the county-level data must be interpreted with caution due to the small sample sizes in many instances.