|ISSN No. 1606-7754 Vol.12 No.1&2 April-August 2004|
Temporal trends in pregnancy outcome of Maltese Diabetic patients
Diabetic Pregnancy Joint Clinic, Department of Obstetrics and Gynaecology, St. Luke's Teaching Hospital, Malta
Complications attributable to diabetes mellitus account for a significant proportion of pregnancy complications in the Maltese population. The intervention strategies that have been introduced in the last decades in obstetric practice should help to favourably alter the obstetric outcome of these pregnancies. The study reviewed the outcome indicators of pre-existing and gestational diabetic pregnancies in the Maltese population over a 15-year interval comparing the periods 1983-1986 and 1999-2002. The study has shown an increase from 0.22% to 0.35% in the prevalence of pre-existing diabetes mellitus in pregnant women, the increase being more marked in the younger age groups. The incidence of gestational DM also showed an increase from 1.25% to 2.40% reflecting a more active screening policy. In both groups, there has been a definite gain in perinatal survival and a drop in macrosomia rate; however associated with a relative rise in low birth weight resulting from earlier intervention by induction of labour and caesarian section
Key words: Diabetes Mellitus, Pregnancy, outcome, Malta
Diabetes Mellitus has become a major medical problem in the Maltese population. In the early 1980ís the prevalence rate for Diabetes Mellitus in the female population of the Central Mediterranean island was found to be 15.2%. The condition was commoner in the elderly population so that the prevalence in women of reproductive age amounted to only 2.2% [Impaired Glucose Tolerance (IGT): 1.7%; Diabetes Mellitus (DM): 0.5%].1 Diabetes in pregnancy can present itself in two clinical situations. Pregnancy can occur in a previously existing diabetic [Pre-DM], or it can appear de novo during pregnancy [Gestational DM]. The medical management of pregnant women suffering from diabetes in Malta has been marked by the introduction of a dedicated combined clinic. There have also been definite changes in overall obstetric practice with a greater predisposition to intervention and a rise in Caesarian section rates.2 It is assumed that the increased metabolic surveillance and increased intervention rates would result in an improvement in obstetric outcome indicators. The present study attempts to assess the obstetric outcome changes that have occurred in the Maltese pregnant diabetic population over the last two decades.
Materials and Methods
The study population was from two databases commissioned by the Department of Obstetrics-Gynaecology [Department of Health, Malta]. The first database included all the deliveries that occurred at St. Luke's Hospital, Malta during the period 1983-1986. This included a total of 20,072 deliveries with 20,335 births, accounting for about 88.7% of all the deliveries occurring on the Maltese Islands during the period. The database was collected on non-identifiable data sheets and managed by the Government Computer Center [Malta]. This database formed the basis of several annual reports and epidemiological studies including those related to diabetic pregnancies. 3 This database also contained information about diabetic pregnancies including 44 pre-DM and 251 Gestational DM and IGT [GDM/GIGT] cases as defined by the 1980 WHO criteria.4
The second database included all the deliveries that occurred in the Maltese Islands during the period 1999-2002. This included a total of 16,413 deliveries with 16,641 births. The data is collected and managed by the Department of Health Information [Malta] using the National Obstetric Information Service database and forms the basis of regular annual reports. This was supplemented by a specific database kept by the Diabetic Pregnancy Joint Clinic [Malta] on all diabetic pregnancies. This included a total of 16,413 deliveries of which 57 were pre-DM cases and 394 cases of GDM/GIGT as defined by the WHO criteria.
These databases furnished basic information pertaining to obstetric outcomes in the diabetic pregnancies including maternal complications, such as multiple pregnancy, induction, caesarian section, operative vaginal delivery and preterm delivery, and neonatal complications, such as perinatal mortality, low birth weight, macrosomia, low Apgar, respiratory distress and congenital malformations.
Ethical considerations: No ethical restraints were associated with the study design. The study was carried out within the legal and ethical confines of the Data Protection Act [Malta], since all the data collected and processed ensured patient anonymity at all stages of the study. The relevant ethical supervisory body approved the study.
Statistical analysis: Statistical significance was tested using the Yates modification of the Chi Square test and Fisher exact tests as appropriate using the StatCalc (WHO ver.6) statistical package. A probability value of 0.05 was taken to represent a significant correlation.