Page Last Updated: May 13, 2026
Pregnancy & Infant Health Instruments🔗
Health V1 & V2 instruments include the following:
| Instrument | Acronym | Construct | Table Name |
|---|---|---|---|
| ADMINISTERED VISIT 1 | |||
| Health V1- Health History | Healthhx | Pre-pregnancy and pregnancy health | pex_bm_health_preg__healthhx |
| Health V1- Exposures & Vaccines | Vacc | Vaccines in pregnancy | pex_bm_health_preg__exp__vacc |
| Health V1- Chronic Conditions | Chroncond | Chronic conditions/STIs in pregnancy | pex_bm_health_preg__chroncond |
| Health V1- Illness | Illness | Illness in pregnancy | pex_bm_health_preg__illness |
| Health V1- ER Admissions | ERhosp | ER or hospitalization in pregnancy | pex_bm_health_preg__erhosp |
| Health V1- Medications | Meds | Medications in pregnancy | pex_bm_health_preg__meds |
| ADMINISTERED VISIT 2 | |||
| Health V2- Pregnancy | Healthv2 Preg | Health updates up to delivery | pex_bm_healthv2_preg |
| Health V2- Infancy | Healthv2 Inf | Delivery and birth outcomes | pex_bm_healthv2_inf |
Quality control procedures include reviewing response distributions for outliers.
| Instrument | Child-Specific | Respondent | Administration Method | Completion |
|---|---|---|---|---|
| Healthhx | No | Pregnant Participant | Self-Administered | 5 min |
| Vacc | No | Pregnant Participant | Self-Administered | 3 min |
| Chroncond | No | Pregnant Participant | Self-Administered, in person | 3 min |
| Illness | No | Pregnant Participant | HBCD Study Staff, in-person | 3 min |
| ERhosp | No | Pregnant Participant | HBCD Study Staff, in-person | 5 min |
| Meds | No | Pregnant Participant | HBCD Study Staff, in-person | 5 min |
| Healthv2 Preg | No | Birth Parent | HBCD Study Staff (in person) | 10 min |
| Healthv2 Inf | Yes | Birth Parent or Primary Caregiver on Child | HBCD Study Staff (in person) | 10 min |
Instrument Details🔗
Health V1- Health History (Healthhx)🔗
Amidst powerful societal expectations to ‘do what’s best for the baby’ during pregnancy (i.e. by stopping substance use), up to half of pregnancies in the United States are unintended with 1 in 5 unwanted (Bearak et al. 2020). This discrepancy contributes to implicit bias against pregnant individuals who use substances as ‘not caring about their babies’ which is neither humane, nor evidence based (Massey et al., 2022). While cessation of substance use during pregnancy is universally recognized as optimal, the ability to make this “parental” sacrifice varies substantially between birthing individuals and within individuals between their different pregnancies (Level et al., 2024). Failure to recognize this inherent heterogeneity in pregnancy intention stigmatizes substance users who did not intend to want to become pregnant. Summarily, inclusion of pregnancy intention as a covariate in all studies that characterize prenatal substance exposure (in the absence of a strong justification otherwise) is thus strongly recommended to acknowledge myriad experiences of birthing parents who participated in HBCD who made this research possible.
Note that the field pex_bm_health_preg__healthhx_002__01 ("Approximately how many weeks into your pregnancy were you when you found out that you were pregnant?") is currently blank, but will be populated in the next release.
Pre-pregnancy and pregnancy health outcomes, including: gravidity and parity, height and weight, pregnancy intentions, use of assisted reproductive technology, start of prenatal care, prenatal vitamin or aspirin use, secondhand smoke.
Health V1- Exposures & Vaccines (Vacc)🔗
Vaccines in pregnancy, including receipt of common vaccines in pregnancy and trimester received.
Health V1- Chronic Conditions (Chroncond)🔗
Information on chronic conditions and sexually transmitted infections (STIs) during pregnancy, including whether they are ongoing or resolved.
Health V1- Illness (Illness)🔗
Illnesses are captured either from ICD codes (from BioPortal ICD) or WHO (World Health Organization) symptom codes, which were at times difficult for the participant to name or the HBCD staff to correctly find in the ICD or symptom database.
Illness in pregnancy, including start and stop dates and whether the person had a fever.
Health V1- ER Admissions (ERhosp)🔗
Reasons for ER visit or hospitalization are captured from ICD codes (from BioPortal ICD), which were at times difficult for the participant to name or HBCD study staff to correctly find in the ICD database. This was particularly apparent for ER visits for routine care (no diagnosis) or false alarms (e.g., suspected water break), frequently coded as "Don’t know."
ER visit(s) or hospitalization(s) during pregnancy, including occurrence(s) and reason(s).
Health V1- Medications (Meds)🔗
Medication names are queried from the RxNORM database and reasons for medication use are captured from ICD codes (from BioPortal ICD). Reasons for use were sometimes difficult for the participant to name and/or HBCD study staff to find in the ICD database. This was apparent with aspirin for preeclampsia prevention, as there was not an option for coding preventive use. Aspirin was later moved to the prenatal vitamin section as a result. Additionally, medications used PRN (“as needed”) were difficult for participants to report. Finally, although not asked, some medications were coded with dose, but this was not asked and should not be used.
Medications used during pregnancy (since last menstrual period), including prescription and over-the-counter medications. It includes details such as the name of the medication, its indication, frequency of use, and start/stop dates.
Health V2- Pregnancy (Healthv2 Preg)🔗
The same coding issues identified at V1, including difficulty with ICD codes (from BioPortal ICD) and medication names (from RxNORM) apply to this visit as well.
Health updates for the birth parent between enrollment and delivery, including: prenatal vitamin use, aspirin intake, infections and illnesses, vaccinations, medication use (ongoing and newly prescribed), pregnancy complications (e.g., gestational diabetes), labor and delivery details (e.g., delivery method, location, and hospital stay duration).
Health V2- Infancy (Healthv2 Inf)🔗
Coding Issues
The same coding issues identified at V1, including difficulty with ICD codes (from BioPortal ICD) and medication names (from RxNORM) apply to this visit as well.
Filters
Out-of-range values were filtered (i.e. changed to "n/a") for the following Health V2- Infancy fields:
| Field Name | Field Description | Valid Range |
|---|---|---|
pex_bm_healthv2_inf_001__01 | Weight at birth (oz) | ≤ 16 |
pex_bm_healthv2_inf_001__02 | Weight at birth (lbs) | ≤ 66 |
pex_bm_healthv2_inf_002 | Length at birth (inches) | 12 - 51 |
pex_bm_healthv2_inf_002__01 | Calculated length at birth (cm) | 30 - 130 |
Delivery and birth outcomes, including: infant characteristics (birth weight & length, duration of hospital stay); newborn conditions (birth defects, genetic diagnoses); medical interventions including NICU admission and length of stay, intubation, adverse outcomes (e.g. bronchopulmonary dysplasia, congenital syphilis), medications (name, indication, status), healthcare access, specialist visits, and newborn hearing test results.
References🔗
Bearak, J., Popinchalk, A., Ganatra, B., Moller, A.-B., Tunçalp, Ö., Beavin, C., Kwok, L., & Alkema, L. (2020). Unintended pregnancy and abortion by income, region, and the legal status of abortion: estimates from a comprehensive model for 1990-2019. The Lancet. Global Health, 8(9), e1152–e1161. https://doi.org/10.1016/S2214-109X(20)30315-6
Level, R. A., Zhang, Y., Tiemeier, H., Estabrook, R., Shaw, D. S., Leve, L. D., Wakschlag, L. S., Reiss, D., Neiderhiser, J. M., & Massey, S. H. (2024). Unique influences of pregnancy and anticipated parenting on cigarette smoking: results and implications of a within-person, between-pregnancy study. Archives of Women’s Mental Health, 27(2), 301–308. https://doi.org/10.1007/s00737-023-01396-z
Massey, S. H., Neiderhiser, J. M., Shaw, D. S., Leve, L. D., Ganiban, J. M., & Reiss, D. (2012). Maternal self concept as a provider and cessation of substance use during pregnancy. Addictive Behaviors, 37(8), 956–961. https://doi.org/10.1016/j.addbeh.2012.04.002
Massey, S. H., Estabrook, R., Lapping-Carr, L., Newmark, R. L., Decety, J., Wisner, K. L., & Wakschlag, L. S. (2022). Are empathic processes mechanisms of pregnancy’s protective effect on smoking? Identification of a novel target for preventive intervention. Social Science & Medicine (1982), 305(115071), 115071. https://doi.org/10.1016/j.socscimed.2022.115071
Schoenaker, D. A. J. M., Ploubidis, G. B., Goodman, A., & Mishra, G. D. (2017). Factors across the life course predict women’s change in smoking behaviour during pregnancy and in midlife: results from the National Child Development Study. Journal of Epidemiology and Community Health, 71(12), 1137–1144. https://doi.org/10.1136/jech-2017-209493