[Maternal mortality decrease at IMSS, 2000-2005. As a result of specific actions or by chance?]

to assessment the epidemiological characteristics and evolution of maternal hospital deaths at Instituto Mexicano del Seguro Social (IMSS) on the years 2000-2005 and to analyze a possible relation with a specific program to reduce it, starting in 2001.

we collected and studied data about 253 and 144 hospital maternal deaths between 2000 and 2005, respectively. We compared rates, causes, type of obstetrical death, age, parity, history of prenatal care and preventability at admission in hospitals were the women died. Data about live births in were obtained from the official Information Medical System of IMSS. The analysis was made with descriptive statistical measures and values of chi(2).

the maternal mortality rate fell by 30.8 %, as result of a decline from 39 per 100,000 live births in 2000, to 27 in 2005; the proportion of direct obstetric deaths showed a reduction from 77.1 to 66.7 %; all the specific-age mortality rates felt too, but with some variability. Preeclampsia-eclampsia, hemorrhages and abortion were responsible for more of 50 % of total deaths in both years compared. We did not observe significant changes in other variables.

the reduction in general rate of hospital maternal mortality, in percentage of direct obstetric causes of death and specific-age rates were chronologically coincidental with the development of a program to increase opportunity and quality of obstetric care at the whole institution. The results let us think there is a possible cause-effect relation. It is imperative to conduct a more long-term observation to confirm this epidemiological phenomenon.