*4.2. Limitations*

This study was cross-sectional and we were unable to assess the temporality of associations such as having received information on breastfeeding, how a woman hoped to feed her child, and subsequent breastfeeding behavior. We were also unable to assess supervisor or coworker support of pumping in the workplace pre-partum and its impact on pumping behavior. Survey responses were based on self-report and subject to several biases including but not limited to response bias, nonresponse bias, recall bias, and observation bias. Women who were employed, initiated breastfeeding, or had difficulty breastfeeding may have been more likely to take the survey, respond to all survey questions, and more accurately remember their breastfeeding experiences.

The survey also directed women who were currently on maternity leave or who had recently left their job to also respond to workplace questions. This may have resulted in increased rates of employment, having breastfed, and difficulties breastfeeding than in the entire WIC population. Due to this design effect, we were also unable to reliably identify and analyze the rates of women who were pregnant or gave birth and decided to no longer work (and their workplace environment).

Income, a key factor in the initiation and duration of breastfeeding, was not collected in this study. However, we assumed study participants were of a similar, lower socioeconomic status given they had qualified for the WIC program. All WIC families are at or below 185% of the family poverty level unless they adjunctively qualified through participation in the Supplemental Nutrition Assistance Program, Temporary Assistance for Needy Families Program, and/or Medicaid. The types of jobs and industries reported in our study reflect the low to moderate income of WIC participants. Our study also did not collect the age of the child and we were unable to determine who was still on paid maternity leave at the time of survey administration. Categories for industry were especially broad due to small sample sizes and we were not able to calculate numerous factors related to industry and occupation, employment, and the workplace including occupation alone, additional industries, size of the workplace (greater than or less than 50 people), and exempt versus non-exempt jobs.

Many breastfeeding studies focusing on workplace support by employment type are limited to their sample population [12,21]. This study is limited to women participating in the WIC program and/or mothers with children participating in the WIC program and our findings may not be generalizable outside of this population.
