[Impact of delivery care type on perinatal mortality in Tapachula, Chiapas, southern border of Mexico].

PURPOSE

To know and to explain the effects of the obstetrical assistance on the rate of perinatal mortality in a municipality of the state of Chiapas, Mexico which is distinguished by having a marginal rural zone, another one presenting an important agroindustrial and fishery development and the urban area.

DESIGN

Transversal, epidemiological study. Some localities representing the three different geopolitic areas of the municipality were selected by probabilistic sampling. Field work was done from october 1996 to march 1997.

PARTICIPANTS

Information was obtained by a probabilistic sampling survey of 1,382 pregnancies occurring from 1987 to 1996 in 670 women whose age range was between 15 to 49 years old. The unit of analysis was the set of alive newborns as well as dead newborns (stillbirth) from the 28th week of the gestation period until the first week of extrauterin life.

RESULTS

The analysis showed a rate of perinatal mortality of 36.2 per 1000 alive newborns, the percentage of birth assistance by a midwife is of 40 percent while assistance by a relative of the pregnant, her husband or herself is that of 3.8%. The higher risks of increasing the mortality rate were found to be during the gestation period prior to or up to the 7th month (OR = 23.0, p < 0.05), for the lack of prenatal control (OR = 3.44, p < 0.05) and when birth assistance is provided by the woman's husband or a relative (OR = 3.31, p < 0.01).

CONCLUSION

Empirical midwives are currently assisting up to the 43% of the pregnancies as far as prenatal control is concerned while they assist up to 40% of the actual deliveries, the later varying when moving to the core of the municipality. Statistically important differences in the rate of perinatal mortality were not found regardless of the type of assistance received prior to and during the actual delivery, by a midwife or a physician.