The 30‐minute Synacthen Test in Pregnancy and Labour

Summary Changes in plasma cortisol levels following the 30‐minute Synacthen test were studied in 13 women throughout normal pregnancy and in the non‐pregnant state. The plasma 11 OHCS response to Synacthen was also studied during labour in 9 of the 13 patients. A rise in resting plasma glucocorticoids as pregnancy progressed was found, similar to that described by previous workers. The post synacthen response was normal in early and mid pregnancy, enhanced in the third trimester and diminished during labour. The significance of these results is discussed.