Bribing women to breastfeed is a spectacular waste of money


The BBC is touting a new study claiming that paying women to breastfeed is effective. What it really shows it that bribing women to breastfeed is a spectacular waste of precious healthcare funds.

Offering shopping vouchers to new mothers can encourage them to breastfeed their babies, a study published in JAMA Pediatrics has found.

About 10,000 new mothers in Yorkshire, Derbyshire and Nottinghamshire were offered up to £200 in vouchers as an incentive.

Breastfeeding rates increased in these areas, which typically have low uptake.

The study is Effect of Financial Incentives on Breastfeeding: A Cluster Randomized Clinical Trial by Claire Relton et al.

[pullquote align=”right” cite=”” link=”” color=”” class=”” size=””]The authors spent more than $300,000 to get 300 women to partially breastfeed for 6-8 weeks, $1000 for each additional mother![/pullquote]

According to the authors:

In the intervention (5398 mother-infant dyads) and control(4612 mother-infant dyads) group, the median (interquartile range) percentage of women aged 16 to 44 years was 36.2% (3.0%) and 37.4% (3.6%) years, respectively. After adjusting for baseline breastfeeding prevalence and local government area and weighting to reflect unequal cluster-level breastfeeding prevalence variances, a difference in mean 6- to 8-week breastfeeding prevalence of 5.7 percentage points (37.9% vs 31.7%; 95% CI for adjusted difference, 2.7% to 8.6%; P < .001) in favor of the intervention vs usual care was observed. No significant differences were observed for the mean prevalence of breastfeeding initiation (61.9% vs 57.5%; adjusted mean difference, 2.9 percentage points; 95%, CI, −0.4 to 6.2; P = .08) or the mean prevalence of exclusive breastfeeding at 6 to 8 weeks (27.0% vs 24.1%; adjusted mean difference, 2.3 percentage points; 95% CI, −0.2 to 4.8; P = .07).

In their conclusion they acknowledge the weakness of their data:

Financial incentives may improve breastfeeding rates in areas with low baseline prevalence. Offering a financial incentive to women in areas of England with breastfeeding rates below 40% compared with usual care resulted in a modest but statistically significant increase in breastfeeding prevalence at 6 to 8 weeks. This was measured using routinely collected data.

But the weak data and limited effectiveness are not the biggest problem with the study. The biggest problem is that bribing women to breastfeeding is not remotely cost effective.

According to the authors’ own data, an addition 5.7% of women in the bribery group partially breastfed for 6-8 weeks compared to the control group. That’s approximately 300 women. How much did that increase cost?

This was the payment structure:

The incentive intervention was offered to women condi- tional on their infant receiving any breast milk. The scheme offered shopping vouchers worth £40 (US$50) 5 times based on infant age: 2 days, 10 days, 6 to 8 weeks, 3 months, and 6 months (ie, up to £200/US$250 in total). Vouchers were exchangeable at supermarkets and other retail shops with no restriction on allowable purchases. Receipt of vouchers was conditional on mothers signing a form stating that “my baby is receiving breast milk” and a countersignature from a clini- cian for the statement “I have discussed breastfeeding with mum today.”

Therefore all the woman who partially breastfed for 6-8 weeks received a total of $150. Since 37.9% of 5398 women (2159) partially breastfed for that long, the authors spent nearly $324,000 on those women. In other words, the authors spent more than $300,000 to get 300 women to partially breastfeed for 6-8 weeks, $1000 for each additional mother!

Even with all that money they didn’t increase the breastfeeding initiation rate, the rate of exclusive breastfeeding at 6-8 weeks and they didn’t increase breastfeeding rates at 3 months or 6 months.

Of the nearly $324,000 spent, only $45,000 went to the mothers who had been bribed to breastfeed. Nearly $280,000 was given to mothers who would have breastfed anyway.

The total cost of the program far exceeded the $324,000 because women who partially breastfed for 3 months received and additional $50 and women who partially breastfed for 6 months received an additional $100. All of those women would have breastfed for the same length of time even if they hadn’t received the money. Moreover, the program itself almost certainly cost additional money to administer.

Who could have predicted that such a large amount of money would be wasted? I not only could have predicted it, I did predict it!

In November 2014 I wrote Early results from the “bribe a woman to breastfeed” trial. I discussed the results of an earlier pilot study also written by Relton and colleagues. The pilot study involved only 108 women and a similar voucher scheme. When I did the math I found:

The government spent $1100 per woman to increase the breastfeeding rate and the bulk of that $1100 went to women who were planning to breastfeed anyway…

I predicted that the much larger study would just waste a much larger amount of money and that’s exactly what happened.

Shockingly, you would not know that to read the study because they authors either neglected to calculate or neglected to mention the simple arithmetic that is fundamental to determining whether the study was a success. Getting an additional 300 women to partially breastfeed for 6-8 weeks is likely to have a trivial impact on infant health. So the return on investment of $300,000 to get more women to breastfeed is essentially zero. A zero return on investment is an abject failure.

Just about any healthcare expenditure you can think of would have been a better use of scarce healthcare dollars. But that won’t matter to lactivists. They are so sure that breastfeeding is better for babies that they don’t dare to examine their own findings too closely; they fear that their own studies won’t confirm their prejudices.