Perinatal mortality: changes in the diagnostic panorama 1974-1980

Area of Science:

• Obstetrics and Gynecology
• Neonatalogy
• Perinatology

Background:

• Perinatal mortality (PM) remains a critical indicator of obstetric and neonatal care quality.
• Understanding trends in late abortions (LA), late fetal deaths (LFD), and early neonatal deaths (END) is essential for improving outcomes.
• Accurate gestational age assessment is crucial for classifying and analyzing perinatal events.

Purpose of the Study:

• To analyze trends in late abortions (LA), late fetal deaths (LFD), and early neonatal deaths (END) between 1974-1980.
• To identify the primary causes of early neonatal deaths (END) during the study period.
• To evaluate the impact of evolving obstetric care on perinatal mortality classifications.

Main Methods:

• A continuous survey of 17,813 births with ultrasound-ascertained gestational age.
• Inclusion criteria: late abortions (LA), late fetal deaths (LFD), and early neonatal deaths (END).
• Analysis of mortality causes, gestational age, and sex distribution.

Main Results:

• Total perinatal mortality (PM) was 0.98%, with an early neonatal death (END) rate of 0.51%.
• Lethal malformations became the leading cause of END after 1977, surpassing immaturity.
• Idiopathic Respiratory Distress Syndrome (IRDS) as a cause of END showed a continuous decrease.

Conclusions:

• The causes of early neonatal death (END) shifted from immaturity and IRDS towards lethal malformations over the study period.
• Increased active obstetric care may have reclassified some late abortions (LA) as extremely premature liveborn infants, impacting END statistics.
• The definition and boundaries of perinatal mortality (PM) require ongoing consideration in light of changing clinical practices.