# Risk of preterm birth and peripartal complications after first trimester termination of pregnancy: a retrospective cohort study of 35,897 singleton births

## TL;DR

This study found that having a first trimester abortion is linked to a higher risk of preterm birth and some pregnancy complications later on.

## Contribution

The study shows that prior first trimester termination remains a risk factor for preterm birth and placental retention in high-income settings.

## Key findings

- A history of first trimester TOP was associated with a 44% higher risk of preterm birth.
- Women with six or more TOPs had a 5.21 times higher risk of spontaneous preterm birth.
- Placental retention was also more common in those with a history of TOP.

## Abstract

The objective of this study was to explore whether a history of termination of pregnancy (TOP) in births after 2015 in a high income setting is still linked to preterm birth (PTB) and peripartal complications.

35,897 singleton births from a perinatal center with approximately 5000 births per year between 2015 and 2022 were analyzed. Patients with a history of first trimester TOP (TOP < 15 weeks) were compared to those who had never had a TOP. A two-step statistical approach using Chi-squared analysis and forward-step multiple logistic regression was used to explore the relationship.

4132 individuals (11.51%) had a history of first trimester TOP. Our findings suggest an association between past TOP and a higher risk for PTB (OR = 1.44, 95% CI [1.25–1.67], p < 0.001). This increases with the number of TOP, six or more TOP were associated with the highest odds ratio for spontaneous PTB (OR = 5.21, 95% CI [1.88–14.46], p = 0.002). The risk for PTB did not differ between methods. Furthermore, our data suggest an association between past TOP and placental retention (OR = 1.25, 95% CI [1.03–1.52],p = 0.022).

These findings underscore the importance of still recognizing prior TOP as a risk factor in obstetric care. The results may inform targeted counseling and the development of preventative strategies to mitigate maternal and fetal morbidity.

The online version contains supplementary material available at 10.1007/s00404-025-08242-w.