Relationship between interpregnancy interval and congenital anomalies

Area of Science:

• Reproductive Epidemiology
• Maternal-Fetal Medicine
• Congenital Anomaly Research

Background:

• Interpregnancy interval (IPI) is the time between consecutive births.
• Previous studies suggest a link between IPI and adverse pregnancy outcomes.
• The impact of IPI on congenital anomalies requires further investigation.

Purpose of the Study:

• To evaluate the association between interpregnancy intervals and the occurrence of congenital anomalies.
• To identify specific IPIs that may pose a higher risk for birth defects.

Main Methods:

• Retrospective cohort study of 46,243 women with two consecutive singleton births (1999-2007).
• Linked datasets from provincial health programs used for data extraction.
• Congenital anomalies defined by ICD codes; IPI calculated based on delivery dates and gestational age.

Main Results:

• Overall congenital anomaly rate was 2.2%.
• Both short (0-5 months, aOR 1.32) and long (24-35 months, aOR 1.25) IPIs were significantly associated with increased congenital anomaly risk compared to 12-17 months.
• Associations were significant for folate-independent anomalies.

Conclusions:

• The risk of congenital anomalies is elevated with both short and long interpregnancy intervals.
• Findings support existing literature and provide further detail on affected anomaly types.
• Results have implications for prenatal risk assessment and future research on optimal interpregnancy spacing.