SUNDAY, June 12, 2005 (HealthDay News) -- Treating a pregnant woman who develops mild gestational diabetes not only helps her baby, but it also appears to improve her own quality of life without increasing the risk of Caesarean section, new research finds.
Most pregnant women in the United States are screened and, if appropriate, treated for gestational diabetes. So the study, the largest of its kind, is unlikely to change practice in this country.
In the rest of the world, however, things are different.
"Most of the rest of the world, including the United Kingdom, think we're off the deep end here," said Dr. Michael Greene, director of obstetrics at Massachusetts General Hospital in Boston and the author of an accompanying editorial in the New England Journal of Medicine, which released the study Sunday. "It's a legitimate, bona fide bone of contention as to whether or not people should be screening and treated."
"This study is the most rigorous, best done study on this topic," Greene added. "When you add the results of this methodologically rigorous large trial to everything that's gone before it, I think it's hard not to come to the conclusion that it's time for everybody to be screened and treated."
The findings, which will appear in the June 16 issue of the journal, were released early to coincide with a presentation Sunday at the American Diabetes Association's annual meeting in San Diego.
According to the authors, gestational, or pregnancy-related, diabetes occurs in 2 percent to 9 percent of all pregnancies. Women who develop this condition are at a higher risk for developing diabetes in later life. In addition, their babies tend to be larger than average when they are born, which can lead to difficulties during birth -- including injury to the baby, the researchers said.
Despite the risks, it has not been clear whether screening and treatment would help. Many experts have worried that treatment might increase the risk of Caesarean section, induce labor and increase anxiety and depression in the mother.
Enter the Australian Carbohydrate Intolerance Study in Pregnant Women, designed to see if treatment of gestational diabetes would reduce complications during pregnancy and to see if there were any effects on the mother.
One thousand women who were 24 to 34 weeks pregnant and who had gestational diabetes were randomly assigned to receive treatment (dietary advice, blood glucose monitoring and insulin therapy, if needed) or routine care.
Only 1 percent of the women in the treatment group had serious complications versus 4 percent in the routine-care group. This may have reflected the fact that infants born to mothers in the treatment group had lower birth weights, itself a reflection of the fact that they tended to be born earlier. There was also a reduction in the risk of preeclampsia, a condition characterized by potentially life-threatening elevations in blood pressure.
On the other hand, more infants of women in the treatment group were admitted to the neonatal nursery (71 percent versus 61 percent). Also, women in the treatment group were more likely to have induced labor (39 percent versus 29 percent). These higher rates may have reflected higher levels of vigilance on the part of the physician, said the study authors.
The rates of Caesarean delivery were almost identical in both groups -- 31 percent and 32 percent.
At three months after birth, women in the treatment group had lower rates of depression and better quality of life, the researchers add.
Although the trial did not address the issue of screening for gestational diabetes, "the results indicating that serious perinatal morbidity is reduced by treatment provides a strong impetus for screening as occurred for most recruited into the trial," said Dr. Jeffrey Robinson, senior author of the study and the head of the obstetrics and gynaecology department at Adelaide University.
There are still many unanswered questions, including what level of blood glucose warrants treatment, he added.
"There needs to be further work on the cut-off concentration of glucose that is used to identify women with gestational diabetes," Robinson said. "It will also be important to follow-up both the women and their offspring to determine if there are long-term benefits from treatment of mild gestational diabetes."
Dr. Victor Hugo Gonzalez-Quintero, director of Maternal Fetal Medicine at the University of Miami School of Medicine, who was not involved with the study, said it would be interesting to see if such treatment helps to reduce the risk of developing cardiovascular disease because women who have gestational diabetes are more prone to this problem later in life.
The study also highlights possibilities that exist during pregnancy to affect other health outcomes.
"Pregnancy is a very, very special time because most of us, including men, don't see a doctor so often," Gonzalez-Quintero said. "This is a great opportunity for the obstetrician to do a lot of primary care, not just to talk about these 42 weeks but to talk about what's going to happen once the baby is born and five, 10, 15 years down the road."
The American Diabetes Association has more on gestational diabetes.