Direct Measurements of Cervical Remodeling for Predicting Preterm Birth

Preterm birth (PTB) is currently the most important maternal and child health problem in the United States. It is the leading cause of neonatal mortality and a significant contributor to neonatal morbidity. In the United States, approximately 12% of all live births are born preterm, an incidence that continues to rise. The extreme cost of PTB resides not only in the immediate neonatal care but also in the longterm care of lasting morbidities resulting from prematurity. Effective prevention or treatment of PTB could significantly lower neonatal mortality and morbidity as well as health care costs. In the United States, PTB costs on the order of 28 billion dollars a year. But, this cost does not stop at the delivery. The costs of prolonged hospital care after birth and the increased need for hospital admission during the first year of life for ex-preterm infants is significant and confers a large economic burden on our society.

It is well known that PTB rates in the United States are highest for Black infants (17.9%), followed by Native Americans (14%), White infants (11.8%), and Asian infants (10%). The specific large disparity between black and white infants is striking and the etiology of this disparity is not fully understood. This disparity persists even after adjusting for socioeconomic status. Maternal stress has been implicated as a potential cause of PTB. Racism is a potent lifetime stressor in the lives of Black women in particular. It is plausible that perceptions of racism as well as distrust in the health care system may explain the persistent racial disparities in PTB, especially through mediation of other factors associated with premature birth. The data to date offer a preventative strategy only to those women with a prior PTB. These women represent a small percent of all women with a PTB. More then half of all PTB occur in apparently low risk pregnancies. Cervical shortening appears to be a common biological pathway leading to preterm birth, often well in advance of PTB. Regardless of etiology of PTB, cervical change must occur. The cervix must remodel (change) for birth to occur at any gestational age.

We hypothesize that experiences of discrimination and health care system distrust are associated with preterm birth. Further, we hypothesize that premature cervical remodeling occurs weeks prior to actual birth and may be able to be detected in women at highest risk for preterm birth (nulliparous women-women who have not previously carried a pregnancy beyond 15 weeks). This study investigates whether experiences of discrimination and health care system distrust are associated with PTB in all women (group 1). It also investigates if the detection of cervical remodeling (changes in the cervix measured by protein levels, ultrasound length and physical exam) can accurately identify those women at greatest risk for PTB-nulliparous (group 2). A prospective cohort of pregnant women will be enrolled. All enrolled women are asked to complete validated questionnaires about experiences of discrimination and health care system distrust. Nulliparous women are evaluated for cervical change, through a comprehensive evaluation at 18-24 weeks. The main outcome assessed is preterm birth.

Inclusion criteria

• All pregnant women screened at < 18 weeks with a documented singleton pregnancy, who agree to participate in the study (group 1). A subset of Nulliparous women (no previous pregnancy 15 weeks)(group 2) will be assessed.
• Women of all races and age will be included.

Exclusion criteria

• Women with a multi-fetal pregnancy, current use of systemic steroids or immunosuppressive therapy or enrollment for prenatal care after 24 weeks.
• Women with a prior documented history of Leep or Conization will be excluded.
• Any known Mullerian anomalies such as septate uterus, bicornuate or unicornuate uterus will be excluded given that these are high risk groups for preterm delivery.