TARGET Trial

Gestational diabetes (GDM) is a significant health problem affecting one in every 12 pregnant women, or over 5,200 women, in New Zealand annually. GDM has a major, negative impact on maternal and perinatal health with lifelong consequences.

This was a multicentre, randomised, step-wedged trial to determine if implementation of tighter treatment targets for blood sugar control has differential outcomes for mothers with GDM and their babies, compared to current, less stringent targets. The trial compared the relative risk of the baby being born large for gestational age, which is strongly associated with early life and later health problems. More than 1000 mothers and babies at ten sites across New Zealand have taken part. The TARGET Trial was completed in 2018, and results published.

The main finding from the TARGET Trial was that the risk of the baby being born large for gestational age was similar whether the mother used tighter or less tight blood sugar targets during the pregnancy.

Babies born to mothers who used the tighter blood sugar targets, compared to babies whose mothers used the less tight blood sugar targets, were less likely to experience a serious health outcome around the time of birth, although their mothers were slightly more likely to have a serious health outcome at that time.

The results of the TARGET Trial add to the understanding of blood sugar control in gestational diabetes. The Ministry of Health Clinical Practice Guidelines on "Screening, Diagnosis and Management of Gestational Diabetes in New Zealand" recommend the use the tighter blood sugar targets during pregnancy.

Gestational diabetes is known to have some long-term effects for mothers and their children. It is known that mothers have a higher chance of developing type 2 diabetes. For their children, long-term growth & development and metabolism can be influenced. An important, unanswered question is whether different blood sugar targets in pregnancy can be used to positively affect the mother’s and children’s health later in life?

A number of mothers and children who took part in the TARGET Trial participated in this follow up study at 4.5 years. This follow-up study assessed whether tighter targets for blood sugar control during pregnancy for mothers with GDM compared with the less tight targets reduced the mother’s cardiometabolic risk and improved the growth and development of their children 4.5 years later. This follow up has been completed and the results are awaiting publication.

If you have any questions about the TARGET Trial or TARGET 4.5 Year Follow-up you can email the research team at target@auckland.ac.nz.

Crowther CA, Alsweiler JM, Hughes R, Brown J, for the Target Study Group. Tight or less tight glycaemic targets for women with gestational diabetes mellitus for reducing maternal and perinatal morbidity? (TARGET): study protocol for a stepped wedge randomised trial. BMC Pregnancy Childbirth. 2018 Oct 29;18(1):425. doi: 10.1186/s12884-018-2060-2. PMID: 30373539; PMCID: PMC6206938.

Crowther CA, Samuel D, Hughes R, Tran T, Brown J, Alsweiler JM; TARGET Study Group. Tighter or less tight glycaemic targets for women with gestational diabetes mellitus for reducing maternal and perinatal morbidity: A stepped-wedge, cluster-randomised trial. PLoS Med. 2022 Sep 8;19(9):e1004087. doi: 10.1371/journal.pmed.1004087. PMID: 36074760; PMCID: PMC9455881.

Hofer OJ, Martis R, Alsweiler J, Crowther CA. Different intensities of glycaemic control for women with gestational diabetes mellitus. Cochrane Database Syst Rev. 2023 Oct 10;10(10):CD011624. doi: 10.1002/14651858.CD011624.pub3. PMID: 37815094; PMCID: PMC10563388.