1. Cessation of metformin prior to induction of labour; help or hinderance?
Dr K Walker Dr S Mannan Mr A Ikomi
Rationale
Results
Metformin is contra-indicated in conditions such as surgery and dehydration that predispose to lactic acidosis.
Labour is a similar stress condition
Current practice in Basildon is to stop metformin 24 hour prior to induction of labour.
Concerns have been raised that this may predispose women to raised intrapartum glucose levels and its subsequent complications.
53 women in final cohort identified from clinic log of GDM cases. Inclusion criteria; treatment with metformin during pregnancy, clear documentation of cessation of metformin at least 24 hour prior to induction, and underwent induction of labour.
Sliding Scale
Duration of metformin vs % of raised blood sugar readings
Antenatal glycaemic control vs % readings >7mmol/L
None of the women in the study required a sliding scale during labour
Only 1.9% of all blood sugar readings were >9.9mmol/L, and only one patient had more than one reading >9.9mmol/L
There does not appear to be any correlation between the antenatal glycaemic control and the glycaemic control during labour However, there is an uneven spread of patients between the three groups
Proportion of raised blood sugar readings
Aims and Objectives
No correlation between the duration of metformin and percentage of blood sugar readings above range.
To formulate formal guidelines for the pre-delivery management of pregnant women with diabetes taking metformin throughout their pregnancy
Total proportion above ideal range of 7mmol/L – 18% (57/316 women)
Conclusions
Cessation of metformin prior to induction of labour does not appear to have any clear adverse effects on either the mother or the baby
82% of blood sugar readings were within range
No women required treatment with a sliding scale during labour
None of the babies required transfer to NICU.