Age and BMI: Likelihood of Developing Gestational Diabetes

 

In mothers aged 40 years or more,
the rate of GDM had risen to 1.9
per cent;© panthermedia.net/
Ron Chapple

Age and body mass index (BMI) are important risk factors for gestational diabetes mellitus (GDM) particularly amongst South Asian and Black African women finds new research.

The study looked at the link between maternal age, BMI and racial origin with the development of GDM and how they interact with each other. Data were collected on 585,291 pregnancies in women attending for antenatal care and delivery at 15 maternity units in North West London from 1988-2000.The study included 1,688 women who developed GDM and 172,632 who did not.

Maternal age was divided into the following groups: below 20, 20-24, 25-29, 30-34, 35-39 and above 40 years of age. Maternal BMI was also divided according to the WHO international classification of BMI as follows: less than 18.5 (underweight), 18.50-24.99 (normal weight), 25.00-29.99 (overweight) and more or equal to 30.00 (obese). Prevalence of GDM was calculated for each maternal age and BMI group.

There was a strong association between GDM development and advancing maternal age which varied by racial group. Using White European women age 20-24 years as a comparison group, White European women older than 30 years had significantly higher odds ratios (ORs) for developing GDM.

The ORs for GDM development were also significantly higher in the other racial groups but at a younger maternal age (older than 25 years if they were Black Africans or Black Caribbeans and older than 20 years if they were South Asians). Moreover, the rate of GDM rose more rapidly with age. For example, in mothers aged 40 years or more, the rate of GDM had risen to 1.9 per cent in white European mothers (from 0.5 per cent at age 20-24), but to 11.4 per cent in South Asians (from 1.1) and 21.7 per cent in black Africans (from 0.7 per cent). White European women under the age of 20 were the only group to have significantly lower ORs for developing GDM.

In addition, there was also a strong link between GDM and BMI in all the racial groups. Using White European women with a normal BMI as the comparison group, the ORs for developing GDM were significantly higher in the overweight and obese White European and Black Caribbean groups and significantly higher in all BMI categories of Black African and South Asian women.

REHACARE.de; Source: Wiley-Blackwell