Background/introduction Although abortions performed at earlier gestations are relatively medically safer and less costly, nonetheless in many settings there exists a small minority of women who receive abortions in the second trimester. The difficult circumstances faced by women seeking later abortions have been highlighted, but it is not always clear what factors lead to abortions being performed later in pregnancy.

Aim(s)/objectives To identify the causative factors of later (second trimester) abortion, analyse the impact of service provision on timing of abortion and highlight other factors relevant to delay in seeking or obtaining abortion.

Methods A literature search was conducted using Medline and Embase databases, and results were limited to English language studies from the last 20 years in settings where termination of pregnancy was legally available.

Results Most delays tended to act on one or more of three periods: identification of pregnancy, decision-making, and obtaining an abortion having made a decision. Delays in suspecting or confirming the pregnancy were key drivers in later termination and were particularly pronounced in young people; service-related delays were common, though small, and were often compounded by logistical factors such as financial difficulties.

Discussion/conclusion The causes of later abortion are many and complex, and very commonly overlap; more research is needed to analyse how these factors interact to cause delay. The association of low socioeconomic status with increased abortion delay suggests more must be done to ensure the accessibility of abortion services.