Mary T. Sheedy

Identification and Treatment of Women with Hyperglycaemia Diagnosed During Pregnancy Can Significantly Reduce Perinatal Mortality Rates

Summary: We wished to determine whether gestational diabetes was associated with an increased perinatal mortality rate, and to investigate the cause for the observed increase in the incidence of gestational diabetes. We therefore reviewed the results of glucose tolerance tests and pregnancy outcome in 116,303 pregnancies, 1971–1994, at the Mercy Hospital for Women. The main outcome measurements were the presence or absence of gestational diabetes, and perinatal mortality. Over the entire period of the study, gestational diabetes was associated with an increased risk of perinatal mortality (Mantel‐Haenszel adjusted odds ratio 1.53, 95% CI 1.13‐2.06, p=0.0069). Women with gestational diabetes that was only diagnosed retrospectively had a higher perinatal mortality rate than their contemporaries with normal glucose tolerance (OR 2.31,95% CI 1.37‐3.91, p=0.0025). Women in whom a glucose tolerance test was not performed continued to have a higher perinatal mortality rate than women who were tested (adjusted OR 2.21,95% CI 1.56‐3.12, p<0.00001). There has been an increase in the prevalence of gestational diabetes from 2.9% to 8.8%. Some of this is due to changes in population characteristics (increases in maternal age, obesity and proportion from South‐East Asia), but there was still an independent increase over time. We conclude that identification and treatment of women with gestational diabetes can reduce perinatal mortality rates. Similarly to diabetes mellitus in the total population, the prevalence of gestational diabetes has increased over time.

Maternal Serum Triglyceride, Glucose Tolerance, and Neonatal Birth Weight Ratio in Pregnancy: A study within a racially heterogeneous population

OBJECTIVE To determine the value of measuring serum triglyceride (TG) levels early in pregnancy for predicting late-gestation glucose tolerance and neonatal birth weight ratio (BWR) (birth weight corrected for gestational age). RESEARCH DESIGN AND METHODS The relationships between morning nonfasting TG measured early in pregnancy (gestational age 12 ± 6 weeks [mean ± SD]) and glucose tolerance measured by a 3-h 50-g oral glucose tolerance test (OGTT) late in pregnancy (gestational age 30 ± 3 weeks) and BWR were investigated in 388 women attending routine antenatal care. The data were analyzed for all women in addition to subgroups of Australian/Western European-born (n = 246) and Asian-born (n = 97) women. RESULTS Morning nonfasting TG positively correlated with the OGTT glucose area under the curve (OGTT-GAUC) (r = 0.23, P < 0.0001) in all subjects. This correlation was stronger in the subset of subjects who had TG measured between 9 and 12 weeks of gestation (r = 0.35, P = 0.0001) and was particularly strong in Asian-born women who had TG measured within this period (r = 0.71, P < 0.0001). Mean TG and the 2- and 3-h OGTT values were higher in Asian-born subjects compared with Australian/Western European-born subjects (P = 0.004, P < 0.0001, and P = 0.02, respectively). TG correlated positively with BWR in all subjects (r = 0.12, P = 0.02), in Asian-born subjects (r = 0.23, P = 0.02), and in subjects with gestational diabetes mellitus (GDM) (r = 0.60, P = < 0.001). CONCLUSIONS TG, if measured between 9 and 12 weeks of gestation, has moderate predictive value for subsequent glucose tolerance in pregnancy. TG is also predictive of BWR in GDM subjects. Further studies are warranted to investigate the role of early TG measurement in the screening and management of GDM. Metabolic heterogeneity exists between Asian-born and Australian/Western European-born women, the significance of which is still unclear and warrants further study.

Gestational Diabetes and Follow‐up Among Immigrant Vietnam‐born Women

Summary: Gestational diabetes is associated with an increased risk of fetal macrosomia and perinatal death. Immigrant mothers from Vietnam who delivered in the Mercy Hospital for Women between January 1,1979 and December 31,1990 were investigated to assess their risk of gestational diabetes, the factors that were associated with gestational diabetes, and the prevalence of diabetes mellitus on follow‐up. These mothers were compared with Australian‐born mothers attending the same hospital and who delivered in the same period. Using a logistic regression model, gestational diabetes was found to be more common in Vietnam‐born mothers who were older, who were primigravidas, or were underweight and the risk of gestational diabetes increased over the time period of the study. The adjusted relative risk of gestational diabetes for Vietnam‐born women was 1.43 (95% confidence limits 1.10, 1.86) compared with Australian‐born women. The incidence of gestational diabetes was 7.8% (144 of 1,839) in Vietnam‐born mothers and 4.3% (1,173 of 27,086) in Australian‐born mothers. Vietnam‐born mothers also had a greater risk of diabetes mellitus on follow‐up; 25% (17 of 68) of those with follow‐up testing had developed diabetes mellitus within 9 years of diagnosis of gestational diabetes, in comparison with an incidence of 9% (52 of 581) of Australian‐born mothers with follow‐up testing. Vietnam‐born mothers should have glucose tolerance testing performed during pregnancy to detect gestational diabetes and those diagnosed should have long‐term follow‐up to detect the development of diabetes mellitus.

Studies of postnatal diabetes mellitus in women who had gestational diabetes. Part 2. Prevalence and predictors of diabetes mellitus after delivery.

Summary: An important part of the management of women with gestational diabetes (GD) is their subsequent follow‐up after delivery. At this postnatal visit a glucose tolerance test (GTT) is essential. We have analysed the results of the postnatal GTTs in 2,957 women whose pregnancies were complicated by GD. Diabetes mellitus was diagnosed in 59 women (2.0%) in the first 6 months after delivery. As stated in Part 1 of this paper, 31 of these 59 women may have had unrecognized prepregnancy diabetes mellitus. The significant independent predictors of postnatal diabetes mellitus on logistic regression analysis in these women were severity of GD, Asian origin and the 1‐hour plasma glucose level during the antenatal GTT.

Studies of Postnatal Diabetes Mellitus in Women Who Had Gestational Diabetes

Summary: This study investigated the prevalence of undiagnosed diabetes in women in the reproductive age group in a Victorian population by analysis of the results of glucose tolerance testing in 57,563 pregnancies. Gestational diabetes (GD) was diagnosed in 4,243 pregnancies and in 2,957 (69.7%) of these, postnatal glucose tolerance testing was performed. Diabetes mellitus was diagnosed within 26 weeks of delivery in 59 women, 55 of whom were diagnosed by the postnatal glucose tolerance test (GTT). There were 4 women with GD who developed diabetic ketosis during pregnancy (3) or within 12 weeks of delivery (1). By consideration of the results of the antenatal and postnatal GTTs, it was deduced that 53% (31 of 59) of the women with diabetes diagnosed after delivery may have had unrecognized prepregnancy diabetes. Consideration of the entire glucose‐tolerance tested population led to the conclusion that approximately 1 in 1,031 women in the reproductive age group in our community have unrecognized prepregnancy diabetes mellitus.

Excessive Birth Weight and Maternal Glucose Tolerance A 19-year Review

Summary: The incidence of birth‐weight of 4,540 g (10 lb) or more rose from 0.87% in the years 1971 to 1977 to 1.16% in the 12 years from 1978 to 1989 with a concomitant increase in hyperglycaemia in our antenatal population. The relationship between excessive birth‐weight and maternal glucose tolerance was investigated in the light of these observations.

Effect of Follow-Up of Women With Gestational Diabetes on the Ratio of IDDM to NIDDM in Pregnancy

OBJECTIVE We wished to test the hypothesis that the diagnosis of diabetes in women with previous gestational diabetes in our follow-up program had altered the ratio of IDDM to NIDDM in our pregnant population. RESEARCH DESIGN AND METHODS We identified all pregnancies managed at the Mercy Hospital for Women in Melbourne, Australia, from 1971 to 1994 that were complicated by prepregnancy diabetes. In these 374 pregnancies, we identified those women who had previously been diagnosed with gestational diabetes mellitus (GDM). The changing prevalences over time of prepregnancy IDDM and NIDDM, as well as the contribution to both of these conditions made by women who had previously had GDM, were calculated. RESULTS Over the period of the study, there was an increase in the prevalence of IDDM from 0.15 to 0.44% (χ2 for trend, P < 0.00001) and NIDDM from 0.03 to 0.11% (χ2 for trend, P = 0.0001). The proportion of all women with diabetes with NIDDM did not change significantly (16.7–20%). There was a progressive increase in the proportion of women with NIDDM who had had GDM (from 8.3 to 39.1%), but the trend was not statistically significant (P = 0.059). Women with NIDDM were more likely (20 of 64, 31.3%) to have had gestational diabetes in the past than women with IDDM (12 of 310, 3.9%, odds ratio 11.3, 95% CI 5.16–24.7, P < 0.0001). CONCLUSIONS Despite finding relatively young women to have NIDDM, our GDM follow-up clinic has not yet altered significantly the ratio of IDDM to NIDDM in pregnancy.

Amniotic Fluid Insulin Values in Women with Gestational Diabetes as a Predictor of Emerging Diabetes Mellitus

Summary: Amniotic fluid insulin levels were estimated in 30 women with insulin‐dependent diabetes, 216 with gestational diabetes and 27 with normal glucose tolerance. Results were correlated with birth‐weight, incidences of fetal macrosomia and neonatal hypoglycaemia, and the risk of the mothers with gestational diabetes developing diabetes mellitus on follow‐up.

Value of Cardiotoeography in Women with Antepartum Haemorrhage ‐ Is It Too Late for Caesarean Section When the Cardiotocograph Shows Ominous Features?

Summary: Caesarean section is thought to be indicated by an ominous antepartum cardiotocograph (CTG). However, the fear remains that infants delivered for this indication in the presence of antepartum haemorrhage, especially when premature, are destined to have severe hypoxic neurological damage. We therefore reviewed our experience of cardiotoeography in women with antepartum haemorrhage (APH) from 1989 to 1992. There were 472 women with APH who had a CTG performed. Of them, 68 had abruptio placentae and 317 had an APH of undetermined cause. For the group with abruptio placentae, the perinatal mortality rate (PMR) was 230.7 per 1,000 when the CTG was abnormal, but only 18.2 per 1,000 if the CTG was normal (odds ratio 16.2, 95% confidence interval [CI] 1.53–171.9, p = 0.02). For APH of undetermined cause, the corresponding rates were 90.9 per 1,000 and 9.8 per 1,000 (odds ratio 10.1, 95% CI 0.96–105.8, p = 0.13). There were no perinatal losses in women with APH due to placenta praevia (87 cases).

The Significance of Recurrent Polyhydramnios

Summary: A study of 30 women who had polyhydramnios in more than 1 pregnancy revealed that 8 of the 36 resultant pregnancies (22.2%) were associated with diabetes mellitus, 14 (37.8%) with fetal macrosomia, and the perinatal mortality rate was 16.2% (6 of 37). The incidence of major fetal malformations or abnormalities was 18.9% (7 of 37); 4 of the 6 deaths resulted from malformations (anencephalus (2), hydrocephalus (1), nonimmune hydrops (1)), and the other 2 deaths were from hyaline membrane disease associated with prematurity. Recurrent polyhydramnios occurred in 1 in 1,720 pregnancies. The onset was acute in 3, subacute in 2 and chronic in 31, the perinatal deaths in these categories being 2, 1 and 3 respectively. The risk of recurrent polyhydramnios is the risk of fetal malformation and premature delivery. The latter may be preventable by prompt therapy with indomethacin, and serial amniocentesis if this therapy fails.