More Americans consider themselves pro-choice than pro-life for the first time in seven years, a new survey has revealed.

The latest Gallup poll shows that while 44 per cent of Americans identify as pro-life, half (50 per cent) now identify as pro-choice. Analysts say that this is the first time that the pro-choice position has had a "statistically significant lead" since 2008.

According to the Values and Beliefs survey, the biggest change appears to have come in the 35-55 age bracket. The percentage of those who consider themselves pro-choice in this group jumped from 40 per cent in 2012 to 52 per cent in 2015.

The percentage of those aged 18-34 who also identify as pro-choice is only slightly higher, at 53 per cent – but still lower than in 2001, when 55 per cent chose the label.

Both men and women have become increasingly more pro-choice since 2012, but women remain more likely to identify with the movement – in total, 54 per cent of women and 46 per cent of men.

According to Gallup's analysis, though the pro-choice view is not as prevalent in the US as it was in the mid-1990s, "the momentum for the pro-life position that began when Barack Obama took office has yielded to a pro-choice rebound. That rebound has essentially restored views to where they were in 2008; today's views are also similar to those found in 2001."

Analysts also attributed the variation in public opinion on abortion over time to political and cultural events, but said "the broader liberal shift in Americans' ideology of late could mean the recent pro-choice expansion has some staying power."

The issue is more complex than raw data might suggest as many people don't consider themselves either pro-choice or pro-life, but abortion remains a key issue for Americans, particularly with the upcoming election in 2016.

A second Gallup poll, the results of which were also published on Friday, revealed that the number of Americans who say they would only vote for a candidate who shares their views on abortion is the highest it's been in 19 years.

According to the survey, 21 per cent now say this is the case, though the issue is more important for pro-life advocates than those who are pro-choice.