About half of grantees (48 percent) enrolled the majority of their prenatal clients in Healthy Start during the first trimester of pregnancy (See Figure 8). At least some of the difference in the timing of enrollment among grantees appears to be related to the target population of the project. Of those grantees that targeted all women in their catchment area, 59 percent enrolled the majority of pregnant clients in the first trimester of pregnancy. In contrast, of those grantees that targeted high-risk women, only 37 percent enrolled the majority of pregnant clients in the first trimester. This difference may reflect the challenges associated with reaching and enrolling high-risk women early in pregnancy.

The majority of grantees (66 percent) were able to retain more than three-quarters of their pregnant clients as long as they were eligible for participation in Healthy Start (data not shown). Grantees that enrolled the majority of their pregnant clients earlier in their pregnancies retained a greater percentage of their pregnant clients than those that enrolled their clients later (70 percent versus 65 percent).

Grantees identified four major barriers to enrolling and retaining clients in their Healthy Start projects: lack of transportation, unstable housing, mobility of clients, and client belief that Healthy Start services were not a priority (data not shown). A lack of belief in the relative importance of Healthy Start services was the greatest barrier reported for pregnant clients (70 percent), and a lack of housing or client mobility were the greatest barriers during the interconceptional period (64 percent each).