BACKGROUND: The reliability of retrospective time to pregnancy (TTP) has been established, but its validity has been assessed in only 1 study, which had a short follow-up. METHODS: Ninety-nine women enrolled a decade earlier in a prospective TTP study were queried by means of mailed questionnaires about the duration of time they had required to become pregnant. Their responses were compared with their earlier data from daily diaries (gold standard). RESULTS: One-third of women could not recall their earlier TTP either in menstrual cycles or calendar months. Only 17%-19% of women recalled their TTP exactly. Agreement increased to 41%-51%, 65%-72%, and 72%-77% when defined as +/-1, +/-2, and +/-3 months, respectively. Women with longer observed TTPs or previous pregnancies were more likely to under-report their TTP. CONCLUSIONS: The findings raise questions about the commonly assumed validity of self-reported TTP. Recalled TTP may introduce error when estimating fecundability or classifying couples' fecundity status.
BACKGROUND: The reliability of retrospective time to pregnancy (TTP) has been established, but its validity has been assessed in only 1 study, which had a short follow-up. METHODS: Ninety-nine women enrolled a decade earlier in a prospective TTP study were queried by means of mailed questionnaires about the duration of time they had required to become pregnant. Their responses were compared with their earlier data from daily diaries (gold standard). RESULTS: One-third of women could not recall their earlier TTP either in menstrual cycles or calendar months. Only 17%-19% of womenrecalled their TTP exactly. Agreement increased to 41%-51%, 65%-72%, and 72%-77% when defined as +/-1, +/-2, and +/-3 months, respectively. Women with longer observed TTPs or previous pregnancies were more likely to under-report their TTP. CONCLUSIONS: The findings raise questions about the commonly assumed validity of self-reported TTP. Recalled TTP may introduce error when estimating fecundability or classifying couples' fecundity status.
Authors: J W van der Steeg; P Steures; M J C Eijkemans; J D F Habbema; P G A Hompes; F J Broekmans; H J H M van Dessel; P M M Bossuyt; F van der Veen; B W J Mol Journal: Hum Reprod Date: 2006-09-22 Impact factor: 6.918
Authors: T K Jensen; T B Henriksen; N H Hjollund; T Scheike; H Kolstad; A Giwercman; E Ernst; J P Bonde; N E Skakkebaek; J Olsen Journal: Reprod Toxicol Date: 1998 May-Jun Impact factor: 3.143
Authors: Germaine M Buck Louis; Rajeshwari Sundaram; Enrique F Schisterman; Anne M Sweeney; Courtney D Lynch; Robert E Gore-Langton; Zhen Chen; Sungduk Kim; Kathleen L Caldwell; Dana Boyd Barr Journal: Chemosphere Date: 2012-02-04 Impact factor: 7.086
Authors: Kristina W Whitworth; Line S Haug; Azemira Sabaredzovic; Merete Eggesbo; Matthew P Longnecker Journal: Epidemiology Date: 2016-09 Impact factor: 4.822
Authors: Melissa M Smarr; Katherine J Sapra; Alison Gemmill; Linda G Kahn; Lauren A Wise; Courtney D Lynch; Pam Factor-Litvak; Sunni L Mumford; Niels E Skakkebaek; Rémy Slama; Danelle T Lobdell; Joseph B Stanford; Tina Kold Jensen; Elizabeth Heger Boyle; Michael L Eisenberg; Paul J Turek; Rajeshwari Sundaram; Marie E Thoma; Germaine M Buck Louis Journal: Hum Reprod Date: 2017-03-01 Impact factor: 6.918
Authors: Katherine J Sapra; Alexander C McLain; José M Maisog; Rajeshwari Sundaram; Germaine M Buck Louis Journal: Ann Epidemiol Date: 2015-05-07 Impact factor: 3.797
Authors: Katherine J Sapra; Dana B Barr; José M Maisog; Rajeshwari Sundaram; Germaine M Buck Louis Journal: Nicotine Tob Res Date: 2016-05-17 Impact factor: 4.244
Authors: Alexandra J Buck; John E Vena; Bridget M McGuinness; Maureen A Cooney; Germaine M Louis Journal: Environ Health Date: 2010-05-04 Impact factor: 5.984
Authors: Kim G Harley; Amy R Marks; Jonathan Chevrier; Asa Bradman; Andreas Sjödin; Brenda Eskenazi Journal: Environ Health Perspect Date: 2010-01-13 Impact factor: 9.031