Tennessee Connections for Better Birth Outcomes

Women with a history of a prior preterm birth (PTB) have a high probability of a recurrent preterm birth. Some risk factors and health behaviors that contribute to PTB may be amenable to intervention. Home visitation is a promising method to deliver evidence based interventions. We evaluated a system of care designed to reduce preterm births and hospital length of stay in a sample of pregnant women with a history of a PTB. All participants (N = 211) received standard prenatal care. Intervention participants (N = 109) also received home visits by certified nurse-midwives guided by protocols for specific risk factors (e.g., depressive symptoms, abuse, smoking). Data was collected via multiple methods and sources including intervention fidelity assessments. Average age was 27.6 years. Racial breakdown mirrored local demographics. Most women had a partner, a high school education, and Medicaid. Enhanced prenatal care by nurse-midwife home visits may limit some risk factors and shorten intrapartum length of stay for women with a prior PTB. This study contributes to knowledge about evidence-based home visit interventions directed at risk factors associated with PTB.

Preterm births (PTBs) are the leading cause of death in infants under the age of one. Tennessee (TN) is one of the lowest ranking states in the US for rates of PTBs (46th) and infant mortality (48th). Costs for neonatal care increase exponentially with decreasing gestational age, and there are lifelong consequences for families and communities. Despite medications and improved diagnostic tools, a 27% increase in PTBs has occurred in the past 20 years. With a history of one PTB, the probability of another PTB is approximately 30%. The risk of having another PTB rises to almost 70% if the woman has a history of more than one PTB. Relationships between a variety of factors (e.g., African American race, smoking, short interval between pregnancies, socio-environmental stressors) likely contribute to TN's high rate of PTBs. Several interventions have been identified to reduce PTBs and improve maternal and infant health indicators but with varying success; administering intramuscular injections of progesterone between 16 and 36 weeks gestation, providing some prenatal care in the home of women with a high risk pregnancy, increasing the interval between pregnancies, and reducing social factors that negatively impact health, such as smoking, substance abuse and stress.

The overall purpose of this study was to determine if a combined medical and biobehavioral intervention would prevent PTBs and reduce healthcare costs in a sample of women who have had a prior PTB. The medical intervention was conventional prenatal and postpartum clinic care. The biobehavioral intervention included certified nurse midwife home visitors who engaged women in an integrated System of Care (SOC) during their prenatal care. Care continued during the first 18 months of the infant's life by maternal-child nurse visitors. Home visits were in addition to regularly scheduled conventional prenatal and postpartum clinic care. Main study questions were:

Is there a difference in: 1) the length of gestational age of infants of high-risk pregnant women who receive the medical intervention and high-risk pregnant women who receive the SOC? 2) in health care costs between women who receive the medical intervention and the SOC? 3) intervals between the current pregnancy and a subsequent pregnancy across groups? and 4) in length of gestational age of current infant with gestational age of index prior preterm birth?

Eligibility Criteria:
Inclusion Criteria:

* Documented history of previous preterm delivery. Defined as delivery from 20 weeks to 36 weeks 6 days gestation.
* Proven pregnancy
* Reside in Davidson County, Tennessee (TN) or surrounding county in 90 mile driving radius.
* Less than 24 weeks gestation at enrollment
* Will receive prenatal care at a Vnderbilt University Medical Center (VUMC) clinic
* Willing to accept nurse home visits and be randomly assigned to conventional care or care with home visits
* Speaks and understands English
* Between the ages of 18 and 40 years.

Exclusion Criteria:

* Known fetal anomaly that can not be managed conservatively or fetal demise
* Maternal medical or obstetrical complications including:

  * Current or scheduled cervical cerclage
  * PROM in current pregnancy prior to enrollment
* Participation in an antenatal study in which the clinical status or intervention may influence gestational age at delivery
* Profound mental dysfunction or under guardianship