The Swiss have been casting their ballots on whether to legalise or tighten the abortion laws. Polls show a majority will vote in favour of legalisation.
Adoption of the proposal would bring the law into line with reality. Thousands of terminations are carried out in Switzerland each year despite a ban on abortion imposed in 1942.
Polls show a clear majority - 63 percent - in favour of allowing abortion within the first 12 weeks of pregnancy. The move also has the backing of government.
At the same time voters are being asked for their views on a counter proposal, which would tighten the law prohibiting abortion except where a woman's life is in danger.
The "For Mother and Child" initiative seeks an outright ban on abortion, even in cases of rape. Polls show 31 percent in favour of the counter proposal.
Abortion on demand
At present, between 12,000 and 13,000 terminations are performed every year - that is about one in eight pregnancies - because it is left up to the regional health authorities to decide how to interpret the law.
Most of the country's 26 cantons, particularly in urban regions, have introduced more liberal policies in the past few years, effectively offering abortion on demand. Only three small cantons in predominantly Catholic rural areas maintain an outright ban.
As well as having government backing, the proposal to legalise abortion is supported by parliament and two of the four main political parties. The Protestant Church and the country's main women's organisation, Alliance F, also stand behind the proposal.
Tightening the law
Opponents of abortion are also dissatisfied with the present legislation, but for a different reason. The country's main pro-life group, Swiss Aid for Mother and Child, wants to see an outright ban on abortion introduced, even where the pregnancy is the result of rape.
But the group has the open backing of only one fundamentalist religious party. The main women's organisation and the Protestant Church have both come out against the initiative, while the Roman Catholic Church recommends that voters reject both proposals.
Previous votes failed
Sunday's ballot is the fourth vote on abortion in Switzerland since 1977. All previous attempts to either tighten or ease regulations on a nationwide level have failed to win a majority.
But social and political changes in the past 30 years appear to have changed attitudes towards abortion.
Switzerland's abortion rate is among the lowest of any developed country. Nearly half of all abortions are carried out on women over the age of 30, while teenage pregnancies account for about ten per cent of terminations.
Compared with other European countries Switzerland has - in theory - some of the most restrictive abortion laws alongside the Irish Republic, Poland and Portugal.
France and Italy introduced liberal abortion laws in the 1970, while counselling is mandatory in Germany and Austria before a woman can have a termination.