Miriam and Sofia are best friends and enjoyed growing up in the same neighborhood next to the Vondelpark in Amsterdam – one of the richest areas in the city. In her early thirties, Miriam moves to the Bijlmer – one of the poorest neighborhoods of Amsterdam. A while later, Miriam and Sofia meet up for coffee. Miriam excitedly tells Sofia that she is pregnant. Sofia replies: “Me too!”
Miriam and Sofia are both healthy, and lead a healthy lifestyle – they eat enough veggies, go to see their midwife on time, etc. Miriam’s lifestyle has not changed since her move to the Bijlmer, but she lives in a very different neighborhood. Would Miriam’s chances of a healthy baby be any different than Sofia’s, as a result of living in a poor neighborhood?
In other words, do neighborhoods influence birth outcomes,
above and beyond an individual’s health?
The answer you will find in an article my colleagues and I recently published in PLOS ONE is: yes.
The Netherlands is home to one of the highest recorded disparities in birth outcomes across neighborhoods in any developed country. In wealthy neighborhoods in Rotterdam, for example, about 3% of babies are born prematurely. In poorer neighborhoods, over 15% of babies are born prematurely, and therefore have a bad start in life, often leading to long-term developmental problems such as reduced IQ.
Previous studies have shown that the inequalities in birth outcomes across neighborhoods are partially the result of so-called ‘compositional effects’: healthier people tend to live in wealthier neighborhoods, and less healthy people cluster in poorer neighborhoods. We suspected, however, that there might also be ‘contextual effects’, meaning that neighborhoods influence birth outcomes.
But how could neighborhoods influence Miriam’s birth outcomes? There are at least two pathways. First, neighborhoods influence behavior via specific norms and social control. Imagine Miriam – who is visibly pregnant – waiting for the bus, sitting next to a man. Whether this man will light up a cigarette right next to her partially depends on the existing norms in this neighborhood, and how other people would react.
Second, neighborhoods might influence birth outcomes via biological pathways. Miriam has moved to a neighborhood with much higher crime rates and lower levels of social cohesion amongst residents. Miriam is therefore more likely to feel more stressed, and stress is a major risk for premature birth.
To find out whether neighborhoods influence birth outcomes, we used data on the characteristics of all inhabited neighborhoods in the Netherlands (more than 3400 neighborhoods), as well as data on individual characteristics and birth outcomes of all pregnant women in the Netherlands during the last 8 years (about 1,6 million cases).
We found that neighborhoods indeed influence birth outcomes. More specifically, between 2-5% of the variation in birth outcomes can be attributed to neighborhood effects. To go back to Miriam and Sofia: this means that Miriam will have higher chances of an unhealthy baby due to her move to the Bijlmer – a poor neighborhood with lower levels of neighborhood social cohesion. Our results show that both of these characteristics were the strongest neighborhood predictors of adverse birth outcomes.
For Miriam, the negative effects of her neighborhood are bad news. For policy makers however, our study is actually good news. Currently, policies to reduce inequalities in birth outcomes focus on educating women to lead healthy lifestyles – with disappointing results. Our study indicates a new way of improving birth outcomes, namely by adopting a contextual approach. We recommend investing in improving neighborhoods, such as allocating more funds to reducing poverty and crime rates and increasing social cohesion (e.g. by increasing the amount of parks and neighborhood initiatives).
Instead of focusing on educating a small amount of pregnant women, improvements to neighborhoods have the advantage that they influence a large number of residents in the neighborhood. A shift in policy might reduce inequalities in birth outcomes across neighborhoods – and lower the amount of babies that are born into inequality.
Vera Schölmerich completed her joint-PhD at the Department of Obstetrics and Gynaecology (Erasmus Medical Center) & the Department of Organization Sciences (VU University Amsterdam).She is currently an assistant professor at Erasmus University College, Rotterdam.