Objective  To establish the risk of serious complications from severe pre-eclampsia and eclampsia in a region using a common guideline for the management of these conditions.

Design  A five-year prospective study.

Setting  Sixteen maternity units in Yorkshire.

Population  All women managed with severe pre-eclampsia and eclampsia.

Methods  A common guideline was developed for the management of women with these conditions. A network of midwives prospectively collected outcome data.

Main outcome measure  Incidence of the conditions and serious complication rates.

Results  A total of 210,631 women delivered in the 16 units between 1 January 1999 and 31 December 2003. One thousand eighty-seven women were diagnosed with severe pre-eclampsia or eclampsia (5.2/1000). One hundred and fifty-one women had serious complications including 82 women (39/10,000) having eclamptic seizures and 49 women (23/10,000) requiring ICU admission. There were no maternal deaths but 54 out of 1145 babies died before discharge, giving a mortality rate of 47.2/1000. Of the 82 cases of eclampsia, 45 occurred antenatally (55%), 18 before admission to the maternity unit. Eleven cases occurred in labour (13%), including 1 during a caesarean section, and 26 cases occurred following delivery (32%). Twenty-five women developed pulmonary oedema (2.3% of cases) and six women required renal dialysis (0.55% of cases). One hundred and sixty-five (15%) required no antihypertensive therapy and 489 (53%) of the remainder required only oral therapy. Two hundred and one (18.5%) required more than one drug.

Conclusion  A regional guideline for severe pre-eclampsia and eclampsia can be developed and implemented. Its use may contribute to a low rate of serious complications.