Association between short interpregnancy interval and placenta accreta spectrum

Area of Science:

• Reproductive Medicine
• Maternal-Fetal Medicine
• Obstetrics

Background:

• The incidence of placenta accreta spectrum (PAS) is rising, coinciding with an increase in cesarean deliveries.
• Inadequate uterine scar healing after cesarean delivery, potentially due to short interpregnancy intervals, may elevate PAS risk.

Purpose of the Study:

• To investigate the association between short interpregnancy intervals and the risk of developing placenta accreta spectrum.
• To determine if interpregnancy intervals less than 18 months or 12 months are independent risk factors for PAS.

Main Methods:

• Retrospective cohort study of at-risk pregnant individuals (2002-2020).
• Defined short interpregnancy interval as <18 months between delivery and last menstrual period of the next pregnancy.
• Used logistic regression to analyze the association between interpregnancy interval and confirmed PAS, adjusting for covariates.

Main Results:

• No significant association was found between short interpregnancy intervals (<18 months) and placenta accreta spectrum (adjusted odds ratio, 1.04; 95% CI, 0.51-2.15).
• A secondary analysis also showed no association for intervals <12 months (adjusted odds ratio, 0.52; 95% CI, 0.21-1.27).
• Prevalence of previa was similar between short and optimal interpregnancy intervals (P=.09).

Conclusions:

• Short interpregnancy intervals (<18 or <12 months) are not associated with an increased risk of placenta accreta spectrum in at-risk patients.
• Short interpregnancy interval is unlikely to be a significant modifiable independent risk factor for placenta accreta spectrum.
• Further research may explore other factors contributing to the rising incidence of PAS.