Table 1.

List of included regions and methods for diagnosing GDM

Centres	Number of births 2017a	Indication for a diagnostic OGTT									Diagnostic criteria prior to switch (mmol/L)	Method for glucose analysis
		Previous				BMI at booking	FHd	Polyhyd ramnios	Accelerated fetal growth	RPG
		GDM	Macro somiab	LGAc	Stillbirth
1. Stockholm	28,602	T1 & 24–28	24–28			≥35		Yes	Yes	RPGe ≥ 9 mmol/L at booking, week 25, 29, 32/33, 37/38.	FPG < 7.0 and 2-h PG 8.9–11.1	Roche Cobas Beckman Coulter Au. Siemens Advia (hexokinase)
2. Örebro	3565	24–28	24–28			≥35	24–28	Yes	Yes-within 3 days	RPGe ≥ 9 mmol/L at booking, week 24, 28/29, 33, 37.	FPG < 7.0 and 2-h PG 8.9–11.0	Siemens Advia (hexokinase)
3. Västmanland	3120	24–28	24–28			> 35		Yes	Yes	RPGe ≥ 9.0 mmol/L at booking week 25, 30, 35.	FPG < 7.0 and 2-h PG 8.9–11.	Beckman Coulter Au (hexokinase)
4. Dalarna	3232	12–14/24–28	24–28	24–28		> 35	24–28	Yes	Yes	RPGe ≥ 9.0 mmol/L at booking, week 24, 28/29, 33, 37.	FPG < 7.0 and/or 2-h PG 8.9–11.1	Siemens Advia (hexokinase)
5. Uppsala	4200	12–14/24–28	24–28	24–28		≥35	24–28	Yes	Yes	RPGe ≥ 8.8 mmol/L at booking, week 25, 28/29, 33, 37	FPG ≥7.0 and/or 2-h PG ≥10.0	Abbott Architect (hexokinase)
6. Göteborg	9550	25–29	25–29	25–29		≥35	25–29	Yes	(Yes)	Within 1 week if RPGe 8.0–12.1 mmol/L at first antenatal care visit, week 25, 28–29, 35–36.	FPG ≥7.0 and/or 2-h PG ≥10.0 RPGc ≥ 12.2	Nova Biomedical StatStrip TM Multi-Well™ (glucose oxidase)
7. Gotland	538	24–28	24–28		24–28	≥35	24–28	Yes	Yes	RPGe ≥ 9.0 mmol/L at enrollment week 25, 29, 32/33, 37/38.	FPG < 7.0 and 2-h PG 8.9–11.0	HemoCue AB HemoCue 201 RT (glucose dehydrogenase)
8. Halland	4446	12/ 24–28		24–28	24–28	≥30	24–28	Yes	Yes	RPGe ≥ 8.0 mmol/L at enrollment, week 12, 28/29, 32, 37	FPG < 7.0 and 2-h PG 9.0–11.1	HemoCue AB HemoCue 201 RT (glucose dehydrogenase)
9. Malmö	4944	10–12	10–12			≥35	10–12	Yes	No	Capillary 75 g OGTT week 28 in all women. FPGe ≥ 7 and/or 2-h PGe ≥ 10.0 mmol/L indication for a diagnostic OGTT	FPG ≥7.0 and/or 2-h PG ≥9.0	Roche Cobas (hexokinase)
10. Lund	3703	10–12	10–12			≥35	10–12	Yes	No
11. Kristianstad	2085	10–12	10–12			≥35	10–12	Yes	No

Legend: When not otherwise stated, glucose measurement is based on venous plasma

BMI body mass index, FH family history, FPG fasting plasma glucose, IUFD intrauterine fetal death, LGA large for gestational age, OGTT oral glucose tolerance test, PG plasma glucose, RPG random plasma glucose, T1 trimester 1

^aNumber of births per year based on data from the Swedish Medical Birth register year 2017

^bDefined as birth weight ≥ 4.5 kg

^cDefined as birth weight ≥ + 2 standard deviations above the Swedish reference curve [31]

^dIn Dalarna, Malmö, Lund, Kristianstad, Uppsala, Gotland, Halland defined as first degree relative with type 1 or type 2 diabetes, otherwise first degree relative with type 2 diabetes

^eBased on capillary samples