. 2019 Jun 8;42(8):1593–1603. doi: 10.2337/dci19-0028

Table 4.

Guidance on targets for assessment of glycemic control during pregnancy

Diabetes group	TIR		TBR		TAR
Diabetes group	% of readings; time per day	Target range	% of readings; time per day	Below target level	% of readings; time per day	Above target level
Pregnancy, type 1^§	>70%; >16 h, 48 min	63–140 mg/dL^† (3.5–7.8 mmol/L^†)	<4%; <1 h	<63 mg/dL^† (<3.5 mmol/L^†)	<25%; <6 h	>140 mg/dL (>7.8 mmol/L)
Pregnancy, type 1^§	>70%; >16 h, 48 min	63–140 mg/dL^† (3.5–7.8 mmol/L^†)	<1%; <15 min	<54 mg/dL (<3.0 mmol/L)	<25%; <6 h	>140 mg/dL (>7.8 mmol/L)
Pregnancy, type 2/GDM^§	See pregnancy section	63–140 mg/dL^† (3.5–7.8 mmol/L^†)	See pregnancy section	<63 mg/dL^† (<3.5 mmol/L^†)	See pregnancy section	>140 mg/dL (>7.8 mmol/L)
	See pregnancy section	63–140 mg/dL^† (3.5–7.8 mmol/L^†)	See pregnancy section	<54 mg/dL (<3.0 mmol/L)	See pregnancy section	>140 mg/dL (>7.8 mmol/L)

Each incremental 5% increase in TIR is associated with clinically significant benefits for pregnancy in women with type 1 diabetes (59,60).

†Glucose levels are physiologically lower during pregnancy.

§Percentages of TIR are based on limited evidence. More research is needed.