Protocols for PIN3 and PIN3plus
Protocols for PIN3 and PIN3plus
Subject Identification
Recruitment at Prenatal Clinic Visit
Research Center Visit #1
Self-Administered Questionnaire #1
Telephone Interview #1
Research Center Visit #2
Self-Administered Questionnaire #2
Nutrition Assessment
Telephone Interview #2
Delivery Information
Placenta Collection
Postpartum Hospital Contact
Medical Chart Review
Specimen Assays
Contextual Data
Physical Activity Subgroups
Vaginal Bleeding Subgroup
Subject Identification
Potential subjects were 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.
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 asked the woman to participate. If she agreed, the following activities occur:
- the informed consent form was signed
- basic demographic data were collected
- a body-image assessment was completed
If the woman did not agreed to a fasting blood draw, the following specimens were also collected at her recruitment visit:
- 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
Research Center Visit #1
For women who agreed to a fasting blood draw at the UNC General Clinical Research Center, the following specimens were 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
Self-Administered Questionnaire #1
At the clinic recruitment, women were 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 mailed the questionnaire to the PIN Study office.
Telephone Interview #1
Women were 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
Research Center Visit #2
Women were scheduled for a research clinic visit to the UNC General Clinical Research Center when they were between gestational weeks 24 and 29. Women were asked to fast for 8 or more hours, although some women did not fast. At this visit, the following was 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 to assess the cervix and uterine artery flow velocity waveform and umbilical artery waveform. The women were given a video tape image from an abdominal ultrasound.
Self-Administered Questionnaire #2
At the second General Clinical Research Center visit, women were 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 mailed 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.
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
Delivery Information
Delivery logs at the study hospital were examined daily to determine delivery information on all study participants.
Placenta Collection
The placentas of PIN women were collected after delivery, weighed, photographed, and fixed in formalin for pathology assessment of placenta characteristics.
Postpartum Hospital Contact
Project staff contacted 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 were 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 were obtained for the cohort.
Specimen Assays
Various biological specimens were 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
- vitamin D
Contextual Data
Up to four addresses were obtained from each woman during Telephone Interview #2 and these addresses were 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 were 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, were asked to do daily diary cards to record bleeding.