Vaginal birth, breastfeeding associated with lower allergic burden
HOUSTON — Children delivered vaginally and those who were breastfeed had lower odds of developing allergies, according to study results presented at the American College of Asthma, Allergy & Immunology Scientific Meeting.
“These results add to our growing knowledge about the impact of delivery mode and infant feeding mode on predisposition to allergic disease,” Stanislaw J. Gabryszewski, MD, PhD, of the division of allergy and immunology at Children’s Hospital of Philadelphia, told attendees. “They suggest that vaginal delivery and breastfeeding correlate with reduced risk and reduced the burden of allergic disease.”
Although previous study results had suggested that vaginal delivery and breastfeeding were tied to lower risk for single allergic outcomes, no previous studies examined the whether these factors impacted the development of multiple allergies.
To evaluate the impact of delivery and nutrition on multiple conditions, researchers evaluated patients in a virtual birth cohort consisting of infants who were treated at 31 different primary care sites. Software was used to identify patients with zero, at least one, two, three, or four allergic conditions, including eczema, IgE-mediated food allergy and asthma.
Researchers calculated hazard ratio to assess the affects of vaginal and cesarean delivery and how the infant was feed — breastmilk, formula, or both — on developing allergic conditions.
Vaginal delivery was associated with a reduced rate of developing at least one (HR = 0.89; P .001), two (HR = 0.83; P .001), three (HR = 0.84; P .001) and four (HR = 0.79; P .001) allergic conditions.
Breastfeeding alone was associated with a reduced rate of developing at least one (HR = 0.74; P .001), two (HR = 0.75; P .001) or three (HR = 0.89; P .001) conditions, and feeding with both breastmilk and formula was associated with a lower rate of developing at least one condition (HR = 0.94; P .001).
“From a practical standpoint, this suggests that using breastmilk when possible could be predisposed to less allergic disease over time,” Gabryszewski said.
He noted that while there are many factors that go into decisions about feeding and clear indications for cesarean, physicians should consider reduced allergic disease burden with their patients who are undecided on their delivery or feeding method. – by Erin Michael
Gabryszewski SJ, et al. P359. Presented at: American College of Asthma, Allergy & Immunology Scientific Meeting; Nov. 7-11, 2019; Houston.
Disclosures: The study was supported by the NIH NIDDK award and the ACAAI SPARK Program. The authors report no relevant financial disclosures.