Longitudinal trends for diabetes during pregnancy: California 1983-2015

Abstract

Objective: To report longitudinal trends (1983-2015) for pregnant women hospitalized in California
with pre-existing Type 1 or Type 2 diabetes mellitus (PDM) and gestational diabetes mellitus (GDM).
Research design and methods: Using 1983-2015 patient discharge data, we identified admissions of
pregnant California resident women, age 15 to 44 (N = 18,560,269). We used the Clinical Classification
System to classify diagnoses and procedures.

Results: Over the period, 18,952,079 pregnant California-resident women age 15 to 44 were admitted
to hospital. Of these, 212,631 (1.1%) had PDM and 787,361 (4.2%) had GDM. At start-of-period 1983-
1987, the percent of admissions with either condition was about 1% each. By 2013-2015, the PDM
rate rose to 1.5% while the GDM rate rose to 9.1%. Compared to women without diabetes, those with
any diabetes had greater risk and rising trends for co-morbidities and adverse outcomes.

Discussion: It is not clear if these trends reflect real underlying changes in population health or
changes in professional attention to these conditions. Trends may be rising because of different
diagnostic criteria, because of underlying changes in risk factors, or for both reasons.

Conclusions: Regardless of the underlying reason, PDM and GDM pose significant risk to a growing
proportion of California’s pregnant women.