[Family planning and perinatal mortality in the Instituto Mexicano del Seguro Social (IMSS)]. / Planificacion familiar y mortalidad perinatal en el IMSS.

PIP: Despite government efforts in Mexico to reduce maternal and infant mortality through proper medical care, mortality rates remain high. Family planning potentially contributes to reducing mortality of mothers and infants by reducing fertility levels and allowing optimal timing of births. A recent epidemiological study based on a probabilistic sample of newborns in Mexican Institute of Social Security hospitals in metropolitan Mexico City, Guadalajara, and Monterrey allowed evaluation of the association between reproductive risk due to age, parity, and birth interval and perinatal mortality. The analysis demonstrated that rates of perinatal mortality associated with extremely long or extremely short birth intervals in women at high reproductive risk due to pre-pregnancy nutritional status, obstetrical or chronic degenerative pathology, or reproductive pattern were much higher than in low risk births. But when women at reproductive risk had intervals of 1-5 years between the end of one pregnancy and the beginning of the next, their children were at similar risk to those of mothers with no reproductive risks. Good prenatal care reduced the perinatal mortality risk substantially for infants of high-risk mothers, but a negative effect persisted for long intervals. Good birth spacing mitigates the negative influence of pathological conditions associated with age and high parity.^ieng