Changing How We Talk About Pregnancy Weight Gain

As a midwife and researcher, I often hear women talk about the pressure they feel around weight during pregnancy. Some are worried about gaining too much. Others are concerned they're not gaining enough. All want to do the right thing for their baby. But knowing what’s “right” is not always straightforward.

Our team wanted to look more closely at how we support healthy weight gain in pregnancy and whether certain approaches help more than others. We focused on techniques known to support long-term behaviour change — motivational interviewing and cognitive behaviour therapy. These are common in mental health care and weight management outside pregnancy, but what happens when we bring them into maternity care?

To find out, we reviewed 21 studies involving more than 8000 women. Some of the studies used motivational interviewing, others used cognitive behaviour therapy, and many used both. What we found was encouraging: women who received these interventions were more likely to stay within recommended weight gain ranges and, on average, gained less weight during pregnancy than those receiving standard care.

This was especially true for women who had a higher body mass index at the start of pregnancy. And while the overall effect was small, it was consistent. When you consider the risks associated with weight gain outside of guidelines — like gestational diabetes, birth complications, and long-term weight retention — even small improvements can have big impacts.

But it wasn’t all good news. Despite these interventions, a large number of women still gained either more or less than recommended. That tells us something important: weight gain in pregnancy is complex. It’s shaped by more than just diet and exercise. Emotional wellbeing, social context, past experiences, access to care and support all play a role.

It also matters how these interventions are delivered. In-person support or a mix of in-person and remote sessions were more effective than remote-only options. This highlights the value of connection and consistent, compassionate care — especially during pregnancy, when women are making so many life changes.

While the overall quality of evidence from the studies was mixed, the direction was clear. Supporting behaviour change through collaborative, person-centred approaches like motivational interviewing and cognitive behaviour therapy shows promise. But we need to do more.

Future interventions should consider the broader picture — not just what we ask women to do, but how we support them to do it. That includes training clinicians in these techniques and designing care pathways that fit women’s lives and priorities. Pregnancy is not just a physical experience; it is emotional, social, and deeply personal.

Healthy weight gain matters. But so does how we talk about it and how we help women reach their goals in ways that are kind, realistic and sustainable. The next part of my current research plan is to explore how midwives are working in this space, and strategies for helping them to work with women safely, gently and in a way that women want.

Link to full paper: https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-023-15446-9