Low energy diets in the treatment of gestational diabetes.

A randomised prospective study of treatment with dietary restriction alone or insulin therapy with dietary advice was performed in 15 women with glucose intolerance diagnosed early in the third trimester of pregnancy. Twenty-four hour profiles of plasma glucose and 3-hydroxybutyrate were performed before and four weeks after commencing treatment. The effect on neonatal outcome was assessed. The case history of one of the patients in the study was sent to British physicians with a special interest in diabetes to obtain their opinion about the appropriate initial treatment of women with gestational diabetes.

Group B streptococcal colonisation and the outcome of pregnancy.

Vaginal colonisation of pregnant women with group B streptococci (GBS) was not related to age, parity or blood group. There were marked differences between racial groups, Asians having a low colonisation rate and Negroes a high rate. Vaginal GBS colonisation was associated with intrapartum pyrexia, but not with preterm labour, premature rupture of membranes or other complications in labour. Group B streptococci may be an important cause of bacteriuria in pregnancy and their effect on the outcome of pregnancy as urinary pathogens needs further evaluation.

The effect of diet and insulin on metabolic profiles of women with gestational diabetes mellitus.

Twenty women with abnormal glucose tolerance, detected from a routine program of antenatal screening for gestational diabetes mellitus (GDM) at 28 wk, were admitted for 24-h metabolic profiles. They were then alternately allocated to either insulin and dietary restriction or dietary restriction alone and then retested 4 wk later while on therapy. Ten normal controls were assessed twice at similar gestations to the study group. Before treatment, the 20 gestational diabetic subjects had higher mean concentrations of plasma glucose and 3-hydroxybutyrate than the controls for most of the profile, but mean insulin values were similar. Insulin therapy was associated with a reduction in mean glucose concentrations so that the profile was similar to the controls, while in the diet-alone group the reduction was less. The 3-hydroxybutyrate concentrations rose between profiles in the normal group and also rose in those treated by diet alone, but still remained within the upper range of normal even at night. Insulin therapy resulted in a similar 3-hydroxybutyrate profile to the controls. The C-peptide response to breakfast was reduced in both groups to levels below that of the controls. Neonatal outcome indices were similar in the two treatment groups, despite the differences in maternal metabolites, but because of the size of this study, conclusions about the neonate must be tentative.

Is group B streptococcal screening during pregnancy justified?

Twenty-eight per cent of women investigated during pregnancy were carriers of group B streptococci (GBS). The use of broth enrichment was the most significant factor in determining GBS carriage rates. GBS carriage decreased during pregnancy. Transmission of GBS from mother to baby was related to vaginal carriage but rectal carriage in pregnancy was the best predictor of maternal carriage at term. Rectal and vaginal swabs taken at 28 and 36 weeks correctly predicted 92% of intrapartum GBS carriage. Although accurate prediction of intrapartum GBS carriage is possible, mass screening for GBS in pregnancy is unlikely to be cost-effective in those countries with a low incidence of neonatal GBS sepsis.

The effect of intrapartum chemoprophylaxis on the vertical transmission of group B streptococci.

Intrapartum chemoprophylaxis with benzylpenicillin or erythromycin significantly reduced the rate of transmission of group B streptococci (GBS) from mothers colonized during pregnancy to their babies from 45% to 3% (P less than 0.001). None of the babies born to women who were given prophylaxis was colonized with GBS in the first 24 h of life. Six weeks after leaving hospital, however, 23% of the babies in the antibiotic group had become colonized with GBS compared with 44% in the control group. GBS strains resistant and tolerant to both benzyl-penicillin and erythromycin were found in this study. Intrapartum chemoprophylaxis breaks the cycle of GBS transmission at birth and may be useful in preventing early onset GBS disease, but is unlikely to affect late onset infections.

Epidemiology of group B streptococci: one year's experience in an obstetric and special care baby unit.

The epidemiology of group B streptococci (GBS) was studied in an obstetric unit and the related special care baby unit (SCBU). In 1 year 53 (77%) of 69 babies who acquired GBS from their mothers were colonized within 24 h of birth, compared with only 9 (35%) of 38 who acquired GBS from non-maternal sources. While 38 (36%) of 107 GBS colonized babies in the obstetric unit derived the organism from a non-maternal source, the value for the SCBU was only 2 (9%) of 23. In babies rectal and umbilical swabs gave the highest GBS isolation rates. Phage-typing and serotyping suggested that colonized mother baby pairs, rather than staff, were the primary source of hospital acquired GBS. This mode of GBS acquisition did not result in long-term carriage once babies had left hospital. Nosocomial transmission can play an important part in GBS epidemiology, but can be minimized by attention to infection control procedures.

Nosocomial transmission of group B streptococci.

The acquisition of group B streptococci by babies in a special-care baby unit and two postnatal wards was investigated over a six-month period using serology and phage typing. Sixty-three culture-positive babies were identified in the postnatal wards, one-third of whom had been born to mothers who were not carrying the organism in the genital tract or anorectal area during labour. A non-maternal source was identified for 14 of these 21 infants: either colonised mothers and babies in the same ward or, on one occasion, a member of the hospital staff. In the special-care baby unit, however, only one instance of nosocomial acquisition of group B streptococci was recorded despite a high prevalence of colonisation in the staff on the unit and the presence of heavily colonised babies. The results of this survey suggest that although sepsis caused by group B streptococci may be the result of nosocomial transmission, this may be prevented by careful attention to hygiene.