The difference in the mortality rate of babies living in the most deprived parts of England and those in the wealthiest areas is wider than at any point in the past 12 years, according to new figures.

Experts warned that an increasing number of pregnant women are facing “social complexities” that are impacting their health, such as poor housing.

They also called for more to be done to tackle underlying factors, such as rising levels of obesity and smoking in pregnancy.

Data published by the Office for National Statistics (ONS) showed there were 6.1 deaths per 1,000 live births in the most deprived areas of England compared to 2.2 deaths per 1,000 births in the least deprived.

The gap is the widest is has been for 12 years, the ONS said.

Regionally, the West Midlands continued to have the highest infant mortality rate with 5.6 deaths per 1,000 live births, while the South West had the lowest, at 2.8 deaths per 1,000 live births.

Clare Livingstone, professional policy advisor at the Royal College of Midwives (RCM), said: “Midwives right across the UK are seeing a growing number of pregnant women experiencing more social complexities.

“There is a growing body of evidence demonstrating the impact of disadvantage, such as poverty and poor housing on pregnancy and birth outcomes.”

Overall, some 2,349 babies under the age of one died in England and Wales in 2022, up slightly from 2,323 in the previous year, the ONS said.

There were 1,019 deaths reported for children aged one to 15, up from 852 in 2021.

This translates to 3.9 infant deaths per 1,000 live births and 10 child deaths per 100,000 people, up from 3.7 and eight respectively.

Babies of black ethnicity continued to have the highest infant mortality rates among all ethnic groups, the ONS said.

Professor Habib Naqvi, chief executive of the NHS Race and Health Observatory, described this statistic “extremely alarming”.

However, the ONS highlighted that small numbers of births and deaths in some ethnic groups can cause larger fluctuations over time.

Prof Naqvi said: “We know there are glaring and persistent inequities in neonatal health outcomes for black and ethnic minority communities.

“These inequities have been documented for decades, but there have been very few targeted interventions to reduce the number of preventable deaths.

“National action must be taken to address why black and ethnic minority women remain significantly and disproportionately affected by poor birth experiences and outcomes.

“Tackling these disparities is paramount to achieving equitable outcomes for all mothers and babies.”

Last month, the RCM launched its Maternity Disadvantage Assessment Tool (MatDAT), which assesses the social needs of pregnant women using a scoring system.

Ms Livingstone added: “MatDAT supports midwives to determine levels of care that are more responsive to women’s needs, but scale of complexity means we must work in partnership with other health and social care professionals and national organisations, and this tool has been evaluated and designed in partnership with other health and social care professionals and third sector organisations.

“Undoubtedly earlier identification and support for health and social risk factors during pregnancy can result in fewer inequalities and greater health equity for black, Asian and minority ethnic women and those from the most disadvantaged areas.

“There is also a need to tackle some of underlying factors, including smoking in pregnancy and rising levels of obesity, both of which can have an impact on infant mortality.”