Preeclampsia intervention trial 4 (PI4)

Preeclampsia is a leading cause of maternal and neonatal morbidity and mortality.

The only cure is delivery, which makes preeclampsia a leading cause of iatrogenic preterm birth with short-and long-term consequences for the child.

A treatment that could prolong pregnancy by even a few days would translate to reduced burden and meaningful improvements for the child.

We recently reported in the BMJ that the anti-diabetic drug metformin extended release (ER) may be the first disease-modifying drug for preeclampsia.

This trial run in South Africa suggested an association of metformin with a 7.6-day prolongation of pregnancy in women with preeclampsia diagnosed before 32 gestational weeks. The effect remains to be proven in other populations with different health care systems.

Therefore, we will now evaluate if metformin ER can prolong pregnancy in a Swedish population of women with early onset preeclampsia.The double blind randomised controlled trial will include 294 women diagnosed with preterm preeclampsia before 34+0 gestational weeks.

The primary aim is to assess if metformin ER can prolong gestation by more than 50%, corresponding to a median prolongation of approximately 4 days and mean prolongation of almost 7 days.

Secondary aims include whether metformin ER can decrease time of neonatal care and increase birthweight.If metformin can prolong pregnancy, there is significant potential to improve short- and long-term outcomes for children born to mothers with preeclampsia.