New Zealand National GDM Guidelines: an alternative view of some good practice points.

The New Zealand Gestational Diabetes Mellitus (GDM) Guidelines, commissioned by the Ministry of Health, contains many good points, but several recommendations are creating controversy. This opinion piece discusses an alternative approach to early pregnancy screening for diabetes. We suggest that it is reasonable to refer women with an HbA1c ≥41 mmol/mol (5.9%) for further management, rather than the recommended referral threshold of ≥50 mmol/mol (6.7%). We also suggest that, for subsequent screening for GDM at 24-28 weeks' gestation, a 75 g oral glucose tolerance test should be offered rather than a 50 g glucose challenge test.

Women with a nondiagnostic 75 g glucose tolerance test but elevated HbA1c in pregnancy: an additional group of women with gestational diabetes.

We examined whether pregnant women with a normal glucose tolerance test (OGTT) by New Zealand (NZ) criteria, but elevated HbA1c are a clinically important group with gestational diabetes (GDM). Eighty women with a normal OGTT and HbA1c > 40 mmol/mol, compared with others with GDM, had a significantly higher BMI and were more likely Pacific. Pharmacotherapy was prescribed in 77.5%. Post-partum OGTT and HbA1c were abnormal in 9/43(20.9%) and 27/42(64.3%), respectively. In 1090 women being screened for GDM by OGTT, most women with GDM had an HbA1c ≤ 40 mmol/mol. In the 22.1% of women with an HbA1c > 40 mmol/mol, the OGTT was normal in 61.8%. For centres using HbA1c to screen for underlying prediabetes/diabetes, these data show that a result >40 mmol/mol identifies women who are likely to require pharmacotherapy. An OGTT is still recommended to diagnose GDM, but these data raise questions about a possible role for HbA1c in high risk women with a nondiagnostic OGTT.

Obstetric interventions for women with type 1 or type 2 diabetes.

OBJECTIVE: To determine whether differences exist in the rates of obstetric intervention between women with type 1 diabetes and those with type 2 diabetes, and whether there has been any change in cesarean rates over time, paralleling that seen in the general obstetric population. METHODS: Data were examined from a prospectively collected series on the outcomes of 1030 deliveries (382 by women with type 1 diabetes, 648 by women with type 2 diabetes) from 1988 to 2008. RESULTS: There was a secular trend to increasing maternal age (type 1, P < 0.003; type 2, P < 0.03). Intervention rates (induction of labor or elective cesarean) did not differ between type 1 (88%) and type 2 (85%) diabetes. The overall cesarean rate was 52%-55% with no secular trend. Poorer glycemic control in early pregnancy and primiparity were associated with primary cesarean in both groups. In women with type 1 diabetes, greater maternal obesity and retinopathy were also associated with primary cesarean. CONCLUSION: Intervention rates are high in pregnancies among women with type 1 diabetes and those with type 2 diabetes but they have not changed significantly. Secular trends toward increasing maternal age and obesity suggest that intervention rates are unlikely to decrease in the near future.

Pregnancy outcome in women presenting with pre-eclampsia at less than 25 weeks gestation.

OBJECTIVE: We aimed to (i) assess maternal and perinatal outcomes in pre-eclampsia at < 25(0) weeks; and (ii) determine if any antenatal factors were associated with adverse maternal and perinatal outcomes. DESIGN: A retrospective study. SETTING: Tertiary referral hospital, Auckland, New Zealand. METHODS: Data were extracted from the clinical record and hospital database. The study population involved women admitted with pre-eclampsia at < 25(0) weeks, with a live singleton pregnancy, from 1997 to 2004 and managed expectantly. OUTCOME MEASURES: Maternal morbidity, perinatal death, neurodevelopmental outcome at 18 months, small for gestational age assessed by population and customised birthweight centiles. RESULTS: Gestation at admission was the only antenatal variable associated with adverse perinatal outcome. Of 14 women admitted < 23 weeks, no babies survived, but eight (62%) babies of women admitted in the 24th week (24(0)-24(6)) survived. Neurodevelopmental outcome was assessed in eight of nine survivors; two (25%) had moderate and two (25%) had minor disability. All babies in this cohort had birthweights < 5th customised centile. Only one baby (10%) weighing < 500 g survived. CONCLUSION: Maternal morbidity was high in this expectantly managed cohort. As no babies survived when pre-eclampsia occurred before 23 weeks, induction of labour should be considered. In the 24th week two-thirds of babies survived and 25% had moderate handicap. This information may help clinicians and women in the future to make informed choices about management.