The past 50 years have brought some huge victories for women’s reproductive choice. Access to contraception and abortion allowed sexually active women to avoid or terminate a pregnancy, enabling them to decide whether and when to have children. But these significant gains are limited by both old and new constraints. Women’s access to abortion is limited by law and remains contingent on the prevailing political mood. And women who continue their pregnancies find themselves subject to increasingly shrill and contradictory guidelines about how that pregnancy should be conducted.

The assumption today appears to be that the choice to become a parent should bring with it the responsibility to create an “optimal womb environment” for the developing foetus. Women are thus cajoled to avoid becoming pregnant “too young” or “too old”; to monitor their eating, drinking and behaviour in accordance with the latest medical advice; and above all, to regulate their emotions and aspirations in line with the orthodoxy that the baby’s (presumed) needs come first.

The constant stream of advice to pregnant women is usually justified with reference to medical knowledge. Because science tells us that eating certain foods or taking certain medications may have an adverse effect on the developing foetus, this is considered to be justification enough for telling pregnant women to avoid all these risky things. But should it be?

The scientific evidence is rarely as clear-cut as it is made out to be. For example, women are now warned that they should not drink any alcohol at all while pregnant (or even if they think they could become pregnant). However, low levels of alcohol consumption during pregnancy have not been shown to cause harm.

But pregnant women are not advised that several nights down the pub during the week is not a good idea. They are told to avoid alcohol altogether for the duration of their pregnancy. This recent shift in official guidance came about, not as a result of changes in the evidence base, but of a perceived need “for clarity and simplicity in providing helpful advice for women and the uncertainties that exist about any completely safe level”.

So in the face of uncertainty, pregnant women are told, “just say no”. Their own ability to calibrate risk and uncertainty – which, let’s face it, is an unavoidable aspect of pregnancy – is diminished, because of an assumption that the most important thing is that women play by the new rules of parenthood. These new rules, invariably, involve bowing to expert advice regardless of your own feelings, knowledge or circumstances.

At the Policing Pregnancy conference, to be held at Canterbury Christ Church University on Thursday, speakers and delegates will discuss what this approach implies about women’s ability to make their own decisions on the basis of the available evidence. Midwives, students, academics and campaigners will explore how risk and benefit is communicated to women today in regard to pregnancy. The conference will also discuss some of the negative consequences of a policy approach that sets out to make pregnant women excessively anxious, and frames the choice to have children as such a risky, problematic endeavour.

One thing we do know for certain is that women have been having babies for many, many years. A civilised society should be focused on caring for pregnant women, not bullying them into submission.