Protocols for PIN3 and PIN3plus

Subject Identification

Potential subjects are identified by study staff through a review of all medical charts of new prenatal patients. Women are excluded if they are less than age 16, non-English speaking, not planning to continue care or deliver at the study site, carrying multiple gestations, or do not have a telephone from which they can complete phone interviews. Some demographic and pregnancy-related data is entered from the medical chart into a computerized tracking file used to date the pregnancy and track study participation.

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Recruitment at Prenatal Clinic Visit

Women are recruited by study staff at their second prenatal visit if they are less than or equal to 20 weeks gestation. Project staff explain the study and ask the woman to participate. If she agrees, the following activities occur:

• the informed consent form is signed
• some basic demographic data are collected
• information about preferred times to schedule the first telephone interview is obtained
• a body-image assessment

If the woman agrees to schedule an appointment for a fasting blood draw, she is scheduled for a visit to the UNC General Clinical Research Center. If she does not agree to the fasting blood draw, the following specimens are collected:

• saliva: for stress hormone assessment (cortisol)
• blood (serum and plasma): for stress hormone assessment (CRH), AFP (from some women), and other potential assessments
• genital tract swabs: for bacterial vaginosis and pH assessment

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Research Center Visit #1

The woman is scheduled for a fasting blood draw at the UNC General Clinical Research Center, where the following specimens are collected:

• saliva: for stress hormone assessment (cortisol)
• blood (serum and plasma): for stress hormone assessment (CRH), lipids, insulin, glucose, AFP, and other potential assessments
• genital tract swabs: for bacterial vaginosis and pH assessment

An ultrasound to assess uterine artery flow velocity waveform is also performed at this visit.

Self-Administered Questionnaire #1

At the clinic recruitment, the woman is given a Self-Administered Questionnaire to assess several psychosocial domains, including:

• social support
• state-trait anxiety
• depression
• pregnancy-related anxiety
• self-esteem
• mastery
• locus of control
• fetal health locus of control
• economic stressors
• family history of cardiovascular disease

Upon completion, the women mail the questionnaire to the PIN Study office in a stamped, pre-addressed envelope.

Telephone Interview #1

Women are called between gestational weeks 17 and 22 and interviewed about the following:

• general health and recognition of pregnancy
• psychosocial measures — life events, perceived stress
• demographic info, household composition, income, religion
• current student status, employment history, job control
• physical activity in the past 7 days — work, recreational, and household activities, transportation
• vaginal bleeding, menstrual history, contraception, pregnancy wantedness
• reproductive history
• father's race, age, education

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Research Center Visit #2

The women are scheduled for a research clinic visit to the UNC General Clinical Research Center when they are between gestational weeks 24 and 29. It is preferred that this visit be after fasting for 8 or more hours, although some women do not present as having fasted. At this visit, the following specimens are collected:

• saliva: for stress hormone assessment (cortisol)
• blood (serum and plasma): for stress hormone assessment (CRH), lipids, insulin, glucose, and other potential assessments
• genital tract swabs: for bacterial vaginosis and pH assessment
• urine: for cotinine (a metabolite of nicotine)
• a vaginal and abdominal ultrasound is performed to assess the cervix and uterine artery flow velocity waveform and umbilical artery waveform

The women are also given a video tape image from an abdominal ultrasound.

Self-Administered Questionnaire #2

At the second General Clinical Research Center visit, women are given a second Self-Administered Questionnaire to assess the following psychosocial domains:

• coping
• depression
• state anxiety
• emotional/physical abuse
• pregnancy-related anxiety
• life events
• sleep quality
• awareness of safety of physical activity during pregnancy

Upon completion, the women mail the questionnaire to the PIN Study office.

Nutrition Assessment

At the second General Clinical Research Center visit, women are given a modified version of the Block Food Frequency Questionnaire to assess diet during the previous three months.

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Telephone Interview #2

Women are interviewed a second time during 27–30 weeks gestation. The following topics are included.

• vaginal bleeding during the pregnancy
• infections — self-report and symptoms
• changes to employment status and job control
• physical activity in the past 7 days and knowledge of physical activity recommendations during pregnancy
• perceived stress
• pregnancy-related anxiety
• experiences of discrimination (racial and gender)
• residential history and perceptions of the neighborhood
• food security
• health behaviors — use of tobacco, alcohol, and drugs
• vitamin and mineral supplement use

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Delivery Information

Delivery logs at the study hospital are examined daily to determine delivery information on all study participants.

Placenta Collection

The placentas of PIN women are collected after delivery, weighed, photographed, and fixed in formalin for pathology assessment of placenta characteristics that might contribute to adverse pregnancy outcomes.

Postpartum Hospital Contact

Project staff contact each woman after delivery to collect a small quantity of hair for drug use assessment during pregnancy and to repeat the physical activity assessment for the 7 days prior to delivery.

Medical Chart Review

Medical charts for all recruited women are examined to assess:

• classification of all preterm births into: idiopathic labor, PROM at least 4 hours prior to labor onset, or medically indicated
• laboratory diagnoses of infection
• pregnancy complications: gestational diabetes, pregnancy-induced hypertension, pre-eclampsia, vaginal bleeding, anemia, receipt of tocolytic drugs
• delivery details: cerclage, presentation, NICU admission, Apgar scores
• ultrasound assessments, placental location
• adequacy of prenatal care (Kotelchuck)
• weight at each prenatal visit
• hospitalizations related to pregnancy

Computerized data sources for laboratory results are obtained for the cohort.

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Specimen Assays

Various biological specimens are assessed for exposures of interest.

Assessments for the full cohort include:

• salivary cortisol
• bacterial vaginosis via gram stain
• corticotropin releasing hormone (CRH)
• alpha-fetoprotein (AFP)
• placenta characteristics

Assessments for a randomly selected subcohort and the preterm cases include:

• hair assessment for cocaine and other drugs
• urine to assess glucose and lipids

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Contextual Data

Up to four addresses are obtained from each woman during Telephone Interview #2 and these addresses will be geocoded with longitude and latitude and Census block group identifiers allowing linkage to contextual data sources.

Physical Activity Subgroups

Validation Subgroup

A subset of women are asked to wear an activity monitor and keep a diary of their physical activity for seven days to compare with their physical activity reports in the interviews.

Reliability Subgroup

A subset of women are asked to repeat the physical activity recall within 48 hours of the initial assessment.

Vaginal Bleeding Subgroup

A subset of women, recruited before 15 weeks gestation, are asked to do daily diary cards to record bleeding.