Created variables

C#DOB: Dates of birth of each child
C#SEX: Gender of each child
C#ID: Identification number of each child
C#RES_DLI: Usual residence of each child at most recent interview
C#DOD: Date of death of each child
Y12110. Number of children ever born
Y12111. Age of R at first birth
Y12111.01. Age of R at second birth
Y12111.02. Age of R at third birth
Y12111.03. Months between first and second births
Y12111.04. Months between second and third births


Important Information

Contraception questions are described in the Sexual Activity, Sex Education & Contraception section of the topical guide.


Interview Data

The fertility section of the Young Adult survey parallels that in the earlier rounds of the NLSY79. However, no information is collected from Young Adults about non-biological children, and information about pregnancies not ending in a live birth is only collected for first pregnancies. In 2000, some of the detailed pre- and postnatal questions that had been collected since 1994 were curtailed.

Pregnancy and birth information. Female respondents who have not reported a pregnancy in a past survey round are asked if and when they have ever been pregnant. The fertility section then includes two paths for collecting fertility information about live births from both male and female respondents. Previously interviewed Young Adults are asked to verify and update their fertility information, while respondents who are Young Adults for the first time in a given survey round have their complete fertility record collected. Basic biological child roster information (gender, date of birth, and name.) is collected for each child.

Female respondents are asked a number of questions about each birth since the last interview, including behaviors that could be detrimental to the child's health, as well as the birth weight and length of the child when born, medical visits during the first year of the baby's life due to sickness or injury, well baby care, and breastfeeding. These questions are modelled after those asked of their mothers in the NLSY79 surveys. Beginning in 2010, male respondents are also asked about the birth weight of their children. From 1994 through 2012, both male and female respondents were asked whether or not they have health insurance for their children.

In 2008, a new sequence on work experiences around the birth of each child was added for female respondents. These questions were modeled after the 1983 maternity leave questions in the NLSY79. In 2008, this series was asked retrospectively about all children. This set of questions has remained in for subsequent years, but is asked only of children for whom these data have not been collected previously. The number of questions asked per child was reduced as part of the 2018 redesign.

Child residence and other parent characteristics. Young Adults answer questions regarding each biological child's residence and contact with each parent. Beginning in 2000, Young Adult respondents who did not live with their children were asked about monetary contributions to each child's upbringing. In 2004, a comparable series of questions was added concerning the monetary contributions of the other parent when the child resides with the Young Adult only. Also new in 2004 were questions directed to Young Adults with spouse/partners about whether the spouse or partner has children from prior relationships, in addition to any currently living in the household, and, if so, what their ages are. Starting in 2008, both male and female respondents were asked about the residence of each of their children immediately after birth and their relationship to the other biological parent at that time. Questions about the height and weight of each child were also added to the residence sequence.

Parenting attitudes and behaviors. Beginning in 2000, the Young Adult Survey has included questions about parenting attitudes and behaviors. From 2000 to 2010, Young Adults with at least one biological child, whether or not their child(ren) were coresidential, were asked a series of questions about their job as a parent. These questions were derived from a series of parenting questions asked of male respondents in the 1998 NLSY79 survey. 

Young Adults with at least one child are asked an extensive series of parenting attitude questions about coresidential children in each round since 2000. Many of these questions are derived from the NLSY79 Mother Supplement and are discussed more fully in the discussion of Child Care in the Young Adult Survey. 

From 2008 to 2016, a series of questions about co-parenting were asked in the residence sequence in the fertility section. This series was designed to be asked each round about each child, regardless of residence status. The 2008 interview also saw the addition of parenting behavior items adapted from the NLSY97. For coresidential children, these questions are asked in the Children in the Household section, and for nonresidential children the series is included with the other questions about residence status. Finally, in each round both male and female respondents are asked about wantedness for each new pregnancy resulting in a live birth.

Fertility Expectations and Desires. The fertility section provides researchers with an opportunity to examine how expectations about the future compare with what actually happens in respondents' lives. In each Young Adult survey round, respondents are asked the number of children they expect to have and when they expect to have their first/next child.

Constructed Biological Child Record

A cleaned set of child-specific data has been created for all respondents ever interviewed as Young Adults. Most of these constructed variables are "yearless" in that they are constructed for all respondents regardless of when they were last interviewed as Young Adults, but Y12051, the year of the most recent Young Adult interview, quickly allows users to identify when these variables were last updated for each respondent. These variables can be found in the "YA Fertility and Relationship Data -- Created" Area of Interest.

Most variables in this section are child-specific. Data are provided on the month and year of birth for each child the Young Adult respondent reports, plus gender, and, if applicable, month and year of death. These data are carefully compared across years, and discrepancies resolved as far as possible. Constructed variables for the last known residence of each child are included. Year-specific usual residence variables are also provided for each child. Users should note that these year-specific variables are created only where appropriate. For example, there are variables for the usual residence of fourth children in 1994, 1996, and since 2000, but not in 1998 because in 1998 an age cap of age 21 at the date of interview was in place and no interviewed respondent had more than three children. Similarly, the usual residence variable for a seventh child is first created in 2000, because that is the first round in which a seventh child was reported.

In addition to the child-specific variables, constructed variables for age at first, second, and third births, as well as months between first and second and second and third births, are available.

Comparison to Other NLS Cohorts: The NLSY79 includes information on fertility and the status of children, with the greatest detail collected from the NLSY79 mothers. Maternal prenatal care information and health-related characteristics are provided on the NLSY79 Child and Young Adult file and are linked to individual children.

Information on fertility and on the status of children has been regularly collected from the NLSY97 and the Original Cohorts. Data include number of children, dates of birth, sex, and life status. For more precise details about the content of each survey, consult the appropriate cohort's User's Guide using the tabs above for more information.

Survey Instruments Questions on fertility are found in the Young Adult Instrument, Section 12, Fertility. Questions about first pregnancies not ending in a live birth were asked in the Young Adult Self-Report Booklet in 1994-1998 and moved to the main Fertility section starting in 2000.
Area of Interest YA Birth Record (data about pregnancies, births, and the first year of life of child)
YA Children's Record Form Biological (unedited child roster data relating to verifying previously reported children and recording any new children)
YA Fertility and Relationship Data--Created (created variables, including cleaned dates of birth of children)