Protocol - Difficulty Getting Pregnant - Current Duration

Description

Depending on the aims of the project and feasibility, there are three widely used methods to assess difficulty getting pregnant or impaired fecundity. These include retrospective assessment, prospective assessment, and the current duration approach.

For the retrospective approach (also the approach used for cross-sectional studies), women or couples are asked if the pregnancy was planned and, if yes, how many months it took to get pregnant. It is important to note that this approach can only be used with women or couples who planned their pregnancies.

For prospective assessment, women or couples are followed over time as they try to get pregnant. Women or couples are asked to record exposure data, menstrual cycle data, intercourse, and pregnancy status prospectively over time. Again, this method can only be employed with women or couples who are planning a pregnancy.

If investigators are interested in exposures among women or couples who are not planning a pregnancy, the current duration approach can be used. For this approach, women or couples are asked about the date that they last used contraception.

Specific Instructions

The PhenX Expert Review Panel recommends this question be asked of either men or women, ages 15 and older.

Availability

Available

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Protocol

1) When did you last use contraception?

_____/_____

Mo Yr

2) Calculate the number of months of unprotected intercourse from the time contraception last used til the date of the interview.

Round up number of months. ___________ months

Personnel and Training Required

None.

Equipment Needs

If a computer-assisted instrument is used, computer software may be necessary to develop the instrument. The interviewer will require a laptop computer/handheld computer to administer a computer-assisted questionnaire.

Requirements

Requirement Category	Required
Major equipment	No
Specialized training	No
Specialized requirements for biospecimen collection	No
Average time of greater than 15 minutes in an unaffected individual	No

Mode of Administration

Interviewer-administered questionnaire

Lifestage

Adolescent, Adult

Participants

Women aged 25 to 44

Selection Rationale

These approaches were chosen to reflect the most modern widely accepted methods of measuring time to pregnancy.

Language

English

Standards

Standard	Name	ID	Source
Human Phenotype Ontology	Infertility	HP:0000789	HPO

Derived Variables

None

Process and Review

The Expert Review Panel #5 (ERP 5) reviewed the measures in the Reproductive Health domain.

Guidance from ERP 5 includes the following:

· Changed the name of the measure

· Replaced protocol

· New Data Dictionary

Back-compatible: there are changes to the Data Dictionary, previous version of the Data Dictionary and Variable mapping in Toolkit archive (link)

Protocol Name from Source

Slama, R., et al, Feasibility of the Current-Duration Approach to Studying Human Fecundity, EPIDEMIOLOGY, 2006

Source

Slama, R., Ducot, B., Carstensen, L., Lorente, C., De La Rochebrochard, E., Leridon, H., Keiding, N., Bouyer, J. (2006). Feasibility of the Current-Duration Approach to Studying Human Fecundity. Epidemiology, 17(4), 440-449.

General References

Buck Louis, G. M., Schisterman, E. F., Sweeney, A. M., Wilcosky, T. C., Gore-Langton, R. E., Lynch, C. D., Boyd Barr, D., Schrader, S. M., Kim, S., Chen, Z., & Sundaram, R.; LIFE Study. (2011). Designing prospective cohort studies for assessing reproductive and developmental toxicity during sensitive windows of human reproduction and development-The LIFE Study. Paediatric and Perinatal Epidemiology, 25(5), 413-424.

Keiding, N., Kvist, K., Hartvig, H., Tvede, M., & Juul, S. (2002). Estimating time to pregnancy from current durations in a cross‐sectional sample. Biostatistics, 3(4), 565-578.

Nguyen, R. H., Baird, D. D. (2005). Accuracy of men’s recall of their partner’s time to pregnancy. Epidemiology, 16(5), 694-698.

Tingen, C., Stanford, J. B., Dunson, D. B. (2004). Methodologic and statistical approaches to studying human fertility and environmental exposure. Environmental Health Perspectives, 112(1), 87-93.

Weinberg, C. R., Baird, D. D., Wilcox, A. J. (1994). Sources of bias in studies of time to pregnancy. Statistics in Medicine, 13(5-7), 671-681.

Protocol ID

100402

Variables

Export Variables

Variable Name	Variable ID	Variable Description	dbGaP Mapping
PX100402_Difficulty_Getting_Pregnant_Current_Duration_Contraception_Last_Use_Month
	PX100402010100	When did you last use contraception? Month	N/A
PX100402_Difficulty_Getting_Pregnant_Current_Duration_Contraception_Last_Use_Year
	PX100402010200	When did you last use contraception? Year	N/A
PX100402_Difficulty_Getting_Pregnant_Current_Duration_Number_Months_Without_Contraception
	PX100402020000	Calculate the number of months of more unprotected intercourse from the time contraception last used til the date of the interview. Round up number of months show less	N/A

Reproductive Health

Measure Name

Difficulty Getting Pregnant

Release Date

April 11, 2017

Definition

Methods to assess the length of time that male and female partners have been trying to get pregnant.

Purpose

These methods ascertain whether a person and his or her partner are trying to become pregnant and how long they have been trying. Difficulty in conceiving may have genetic or epigenetic origins and is also related to lifestyle and environmental exposures.

Keywords

Reproductive health, infertility, pregnancy, Pregnancy Study Online, PRESTO, subfertility, impaired fecundity

Measure Protocols

Protocol ID	Protocol Name
100402	Difficulty Getting Pregnant - Current Duration
100403	Difficulty Getting Pregnant - Prospective Assessment
100404	Difficulty Getting Pregnant - Retrospective Assessment

Publications

There are no publications listed for this protocol.