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A Follow-up of the Early Pregnancy Study Cohort.

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ClinicalTrials.gov Identifier: NCT01132924
Recruitment Status : Completed
First Posted : May 28, 2010
Last Update Posted : October 19, 2017
Information provided by (Responsible Party):

Study Description
Brief Summary:


- The purpose of the 1982 1986 North Carolina Early Pregnancy Study was to determine how often pregnancy loss occurs before women know they are pregnant. Women planning to become pregnant were asked to collect daily urine specimens and fill out daily diaries of their intercourse and menstrual bleeding. Researchers are interested in re-contacting this cohort to gather new information and to examine how accurately women can recall events that occurred earlier in their lives.


- To follow-up with and gather additional information from women who were involved in the Early Pregnancy Study.


- Women who participated in the 1982 1986 North Carolina Early Pregnancy Study.


  • Participants will receive and complete a questionnaire that includes the following topics:
  • Their pregnancy history.
  • The infant s birth, including method of delivery and induction of labor.
  • Early life exposures such as their own birth weight and their parents ages at their birth.
  • Tap water use during their attempt to conceive
  • General description of their behaviors during their participation in the original study, these include: physical activity, caffeine, alcohol, and soy food consumption.
  • Participants will return the surveys to the researchers in the stamped envelope provided with the questionnaire.

Condition or disease
Gestational Age Time to Pregnancy Early Pregnancy Loss

Detailed Description:

We propose a follow-up study of women who participated in the North Carolina Early Pregnancy Study (EPS) in 1982-1986. Women enrolled in the study after discontinuing birth control and were followed for the occurrence of a pregnancy. Participants completed daily diaries and collected first morning urine specimens which allowed the identification of menstrual cycles. Thus each woman s time to pregnancy was prospectively measured. We intend to trace the women and ask them to complete a questionnaire that includes their recall of their time to pregnancy during the study. This will allow us to address two major questions, one regarding the recall of time-to-pregnancy, and the other regarding the natural length of gestation. In addition, we will investigate associations of bisphenal A (BPA), phthalate metabolites, 2,4- and 2,5-dichlorophenols, Triclosan, benzophenone-3, and methyl-, propyl- and butyl-parabens with reproductive outcomes. This is described in a separate section at the end of this protocol because it does not involve recontacting participants, only assay of stored urine samples for purposes within the goals of the original study.

  1. Recall of time-to-pregnancy

    Time to pregnancy is a commonly studied estimate of fecundability. This outcome has been used to study the reproductive effects of environmental toxins, cigarette smoking, obesity and numerous other exposures. Prospective studies of time to pregnancy require enrollment of women who are just starting to attempt pregnancy and following them until a pregnancy is conceived. This type of study can be time-consuming and costly. It is also difficult to identify a population of women who are just beginning to attempt pregnancy. A more efficient design is to ask women to recall their time to pregnancy. This design is limited however, as it is unknown how well women can recall their time to pregnancy. Only two studies have examined this question in a population with both prospective and retrospectively recalled time to pregnancy. One of the studies involved women from the Netherlands, the recall period was short (3-20 months), and only part of the woman s time to pregnancy was prospectively observed. The second study had a longer recall period (1-10 years) but included only 43 women.

  2. Length of gestation

Gestational length is the time from conception to delivery. The EPS has very good data on the first data point, and we know date of delivery. However, our data on delivery is limited by the fact that we do not know which deliveries were induced and which were the product of natural onset of labor and delivery. We plan to collect this information from the mothers. Such information will not only allow us to consider the natural variability in gestational age (a measure that does not exist at present) but also to estimate associations between events in very early pregnancy and the subsequent duration of pregnancy. The EPS has detailed measurements of the time from ovulation to implantation, the rate of increase in human chorionic gonadotropin and corpus luteum rescue. To our knowledge, these early pregnancy characteristics have not been investigated for associations with length of gestation.

Study Design

Study Type : Observational
Estimated Enrollment : 221 participants
Observational Model: Cohort
Time Perspective: Retrospective
Official Title: A Follow-up of the Early Pregnancy Study Cohort
Study Start Date : May 4, 2010
Groups and Cohorts

Outcome Measures

Primary Outcome Measures :
  1. Recall of time to pregnancy.

Secondary Outcome Measures :
  1. Distribution of gestational age in naturally conceived pregnancies.

Eligibility Criteria

Information from the National Library of Medicine

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Ages Eligible for Study:   45 Years to 75 Years   (Adult, Senior)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   No

This study is a follow-up study of women who participated in the NIEHS EPS. All of the women who participated in that study are eligible for this follow-up.

Contacts and Locations

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01132924

United States, North Carolina
NIEHS, Research Triangle Park
Research Triangle Park, North Carolina, United States, 27709
Sponsors and Collaborators
National Institute of Environmental Health Sciences (NIEHS)
Principal Investigator: Donna D Baird, Ph.D. National Institute of Environmental Health Sciences (NIEHS)
More Information

Responsible Party: National Institute of Environmental Health Sciences (NIEHS)
ClinicalTrials.gov Identifier: NCT01132924     History of Changes
Other Study ID Numbers: 999910108
First Posted: May 28, 2010    Key Record Dates
Last Update Posted: October 19, 2017
Last Verified: February 24, 2017

Keywords provided by National Institutes of Health Clinical Center (CC) ( National Institute of Environmental Health Sciences (NIEHS) ):
Early Pregnancy
Gestational Age