Diabetes In Pregnancy

Diabetes Prevalence Estimate and 95% Confidence Interval by Year among Women with a Live Birth, Michigan, MI PRAMS, 2010-2017

Year Gestational Diabetes-Percent and 95% CI Pre-existing Diabetes-Percent and 95% CI
2017 8.0% (6.5%-9.8%) --
2016 8.5% (7.0%-10.3%) --
Note: The wording of diabetes-related questions changed starting in 2016. Consequently, gestational diabetes estimates determined for 2016 and beyond cannot be compared to estimates determined prior to 2016. Due to the change in wording, pre-existing diabetes estimates for 2016 and on are no longer determined. (See Methods and Limitations for further details)
2015 9.0% (7.3%-11.0%) 2.6% (1.8%-3.8%)
2014 6.8% (5.4%-8.7%) 2.1% (1.4%-3.2%)
2013 7.6% (6.1%-9.5%) 2.0% (1.4%-2.8%)
2012 8.8% (7.1%-10.8%) 2.0% (1.4%-3.0%)
2011 8.7% (7.3%-10.4%) 2.8% (2.0%-3.9%)
2010 9.1% (7.5%-11.0%) 2.1% (1.4%-3.2%)

Diabetes Prevalence Estimate by Year among Women with a Live Birth, Michigan, Vital Statistics, 2010-2017

Year Gestational Diabetes Percent Pre-existing Diabetes Percent
2017 5.6% 0.9%
2016 5.3% 0.9%
2015 5.1% 0.8%
2014 5.0% 0.7%
2013 5.1% 0.7%
2012 5.6% 0.8%
2011 5.3% 0.8%
2010 4.4% 0.7%

Data Sources

Michigan Pregnancy Risk Assessment Monitoring System (MI PRAMS), Lifecourse Epidemiology and Genomics Division, Michigan Department of Health and Human Services. (www.michigan.gov/prams)

1989 Michigan Birth Certificate Registry;1990-2017 Geocoded Michigan Birth Certificate Registries. Division for Vital Records and Health Statistics, Michigan Department of Health and Human Services. (www.mdch.state.mi.us/osr/chi/births14/frame.html)

Definitions

Prevalence: The percentage of persons with diabetes condition. The term prevalence can be considered interchangeable with incidence for gestational diabetes. The incidence is the number of persons with diabetes condition divided the susceptible population for a given period.

Confidence Interval (CI): A range about a measurement that expresses the precision of the measurement or a range of values encompassing the true population. A 95% CI can be interpreted as the following: if we selected 100 random samples from the population and used these samples to calculate 100 different confidence intervals, approximately 95 of the intervals would cover the true population estimate and five would not. The wider the interval means the more imprecise the measurement, the narrower the interval the more precise the measurement.

Methods and Limitations

The Michigan Pregnancy Risk Assessment Monitoring System (MI PRAMS) is an annual survey of mothers of live born infants. Initially, a mail survey is administered; however, if there is no response, a telephone survey is conducted. MI PRAMS is self-reported data where women who have elevated levels of blood sugar not in the diabetes range may have answered the question below positively. Self-reported measures are also subject to recall bias.

Gestational Diabetes Indicator (2010-2015): Respondents were considered to have gestational diabetes if they responded "yes" to the question, "During your most recent pregnancy, were you told by a doctor, nurse, or other health care worker that you had gestational diabetes (diabetes that started during this pregnancy)?" Respondents who answered that they had diabetes that started before pregnancy were not included (See Phase 6 and Phase 7 surveys).

Gestational Diabetes Indicator (2016-2022): Respondents were considered to have gestational diabetes if they responded "yes" to the question, "During your most recent pregnancy, did you have any of the following health conditions?" Respondents who answered also respond "yes" to having type I or type II three months before getting pregnant were not included (See Phase 8 survey).

Gestational Diabetes Indicator (2010-2015): Respondents were considered to have pre-existing diabetes if they responded "yes" to the question, "Before you got pregnant with your new baby, were you ever told by a doctor, nurse or other health care worker that you had Type 1 or Type 2 diabetes?" This is not the same as gestational diabetes or diabetes that starts during pregnancy (See Phase 6 and Phase 7 surveys).

Diabetes status is given in the Michigan Resident Birth Files for the mothers. Gestational diabetes information was based on medical records and was differentiated from pre-existing diabetes during pregnancy. Several studies have shown that birth certificates underreported gestational diabetes. Sensitivity studies suggest that 46-83% of pregnancies with gestational diabetes and 47%-52% for pre-pregnancy diabetes were correctly identified on the birth certificate (Devlin, H.M., Desai, J. and Walaszek, A. Matern Child Health J (2009) 13: 660).