Antenatal fetal testing in pregnancies complicated by gestational diabetesmellitus: why, who and how?

Most obstetricians adopt some form of strategy for a antenatal fetal testin g in pregnancies complicated by gestational diabetes mellitus (GDM). There are, however, wide differences of opinion among providers as to the preferr ed protocol for such testing. The optimal method of fetal surveillance, the gestational age at which to start testing, the frequency of testing and ev en whether all patients with GDM require antenatal testing are all controve rsial, unresolved issues. Indeed, in the absence of prospective, randomized clinical trials, it is impossible to determine whether antenatal fetal tes ting is beneficial in uncomplicated GDM. Moreover, it appears that, even wi th the employment of well-defined antenatal testing protocols, it is unavoi dable that some women with GDM will experience an unexplained third-trimest er stillbirth. Not least important are the issues of cost-benefit with a st rategy of universal antenatal testing in GDM and the rate of unnecessary ob stetric interventions that may result from such a strategy. Consequently, t he Diabetes in Pregnancy Study Group of North America has proposed a random ized clinical trial as a first effort to try and resolve some of these perp lexing issues.