Every woman has the right to make informed choices about legal, safe and confidential abortion. The ability to choose legal abortion allows young women to make their own decisions about their futures, including when and whether to have children, and prevents risk to their physical and emotional health.

There are really good reasons for maintaining the current time limit of 24 weeks. Reducing the time limit would affect women at all ages of the spectrum, particularly some of the most vulnerable and disadvantaged women. This may result in women being rushed into decisions about abortions or forced to continue a pregnancy against their will.

There is no scientific evidence to support a reduction of the 24-week time limit. The House of Commons science and technology committee thoroughly investigated scientific developments relating to abortion and concluded that there is no evidence on the grounds of foetal viability to reduce the upper time limit.

This was reinforced by the announcement of headline findings from the EPIcure 2 study which concluded that there had been no significant improvement in the survival of extremely preterm infants born below 24 weeks of gestation in the last 10 years. In England and Wales the figures show that 1 per cent of terminations occur after 20 weeks of pregnancy. This small group of women (of all ages) present later in pregnancy for very good reasons.

Some women may not recognise that they are pregnant because their periods are irregular – this is common in younger women or women approaching the menopause – or because their method of contraception causes their periods to be irregular or to stop altogether.

Poor sex education at school or at home may also mean some young women do not realise they are pregnant. Some will have been using contraception and believe it’s not possible for them to be pregnant or may have had negative pregnancy tests. Fear of the reaction of their parents or partners or fears about the confidentiality of services can deter some young women from seeking help until late in their pregnancy. For some, rejection by their parents causes very real hardship.

Some women experience delays in being referred for an abortion by health professionals who do not declare a conscientious objection or face long waiting times for a hospital appointment. Significant numbers of young women calling the Ask Brook helpline have encountered delaying tactics by their doctors and outright refusal to help without being referred to another doctor.

Changes in their circumstances such as splitting up with their partner, experiencing domestic violence, or losing their job can result in some women changing their mind about continuing with their pregnancy.

A diagnosis of severe foetal abnormality means some parents decide to terminate an otherwise wanted pregnancy. Scans for foetal anomalies are not carried out until around the 20th week of pregnancy and where potential anomalies are identified it can take several more weeks to confirm the diagnosis.

Young women in particular are more likely to present late in their pregnancy. In 2008, 11 per cent of abortions among women under 20 were carried out between 13 and 19 weeks gestation and 2 per cent were carried out at 20 weeks, and over compared to 8 per cent and 1 per cent respectively among women aged 20-34.

Of the small proportion of women who present late in pregnancy some may be victims of rape, in abusive or frightening relationships or those who have been thrown out of home when it was discovered they are pregnant and do not know what to do. These are the kind of vulnerable young people that will be most affected by a reduction to the time limit.

Even a small reduction in the time limit would cause hardship and suffering for women, who may be frightened, confused, and needing time and support to make the right decision for them. Decisions about abortion time limits must remain based on the scientific evidence and not subject to political whim and moral prejudices.