Joseph Barney Stanford1, Sydney Kaye Willis2, Elizabeth Elliott Hatch2, Kenneth Jay Rothman3, Lauren Anne Wise2. 1. Department of Family and Preventive Medicine, Division of Public Health, Office of Cooperative Reproductive Health, University of Utah, Salt Lake City, Utah. Electronic address: joseph.stanford@utah.edu. 2. Department of Epidemiology, Boston University School of Public Health, Boston, Massachusetts. 3. Department of Epidemiology, Boston University School of Public Health, Boston, Massachusetts; RTI International, Research Triangle Park, North Carolina.
Abstract
OBJECTIVE: To quantify the frequency of use of selected fertility awareness indicators and to assess their influence on fecundability. DESIGN: Web-based prospective cohort study. SETTING: Not applicable. PATIENT(S): Female pregnancy planners, aged 21-45 years, attempting conception for ≤6 cycles at study entry. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): We ascertained time to pregnancy, in menstrual cycles, with bimonthly questionnaires. We estimated adjusted fecundability ratios (FRs) and confidence intervals (CIs) using proportional probabilities models, controlling for age, income, education, smoking, intercourse frequency, and other lifestyle and reproductive factors. RESULT(S): A total of 5,688 women were analyzed, with a mean age of 29.9 years and mean time trying of 2.1 cycles at baseline; 30% had ever been pregnant. At baseline, 75% were using one or more fertility indicators (counting days or charting menstrual cycles [71%], measuring basal body temperature [BBT, 21%], monitoring cervical fluid [39%], using urine LH tests [32%], or feeling for changes in position of the cervix [12%]). Women using any fertility indicator at baseline had higher subsequent fecundability (adjusted FR 1.25, 95% CI 1.16-1.35) than those not using any fertility indicators. For each individual indicator, adjusted FRs ranged from 1.28-1.36, where 1.00 would indicate no relation with fecundability. The adjusted FR for women using a combination of charting days, cervical fluid, and urine LH was 1.48 (95% CI 1.31-1.67) relative to women using no fertility indicators. CONCLUSION(S): In a North American preconception cohort study, use of fertility indicators indicating the fertile window was common, and was associated with greater fecundability.
OBJECTIVE: To quantify the frequency of use of selected fertility awareness indicators and to assess their influence on fecundability. DESIGN: Web-based prospective cohort study. SETTING: Not applicable. PATIENT(S): Female pregnancy planners, aged 21-45 years, attempting conception for ≤6 cycles at study entry. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): We ascertained time to pregnancy, in menstrual cycles, with bimonthly questionnaires. We estimated adjusted fecundability ratios (FRs) and confidence intervals (CIs) using proportional probabilities models, controlling for age, income, education, smoking, intercourse frequency, and other lifestyle and reproductive factors. RESULT(S): A total of 5,688 women were analyzed, with a mean age of 29.9 years and mean time trying of 2.1 cycles at baseline; 30% had ever been pregnant. At baseline, 75% were using one or more fertility indicators (counting days or charting menstrual cycles [71%], measuring basal body temperature [BBT, 21%], monitoring cervical fluid [39%], using urine LH tests [32%], or feeling for changes in position of the cervix [12%]). Women using any fertility indicator at baseline had higher subsequent fecundability (adjusted FR 1.25, 95% CI 1.16-1.35) than those not using any fertility indicators. For each individual indicator, adjusted FRs ranged from 1.28-1.36, where 1.00 would indicate no relation with fecundability. The adjusted FR for women using a combination of charting days, cervical fluid, and urine LH was 1.48 (95% CI 1.31-1.67) relative to women using no fertility indicators. CONCLUSION(S): In a North American preconception cohort study, use of fertility indicators indicating the fertile window was common, and was associated with greater fecundability.
Authors: Joseph B Stanford; Sydney K Willis; Elizabeth E Hatch; Kenneth J Rothman; Lauren A Wise Journal: Hum Reprod Date: 2020-10-01 Impact factor: 6.918
Authors: Elizabeth A DeVilbiss; Joseph B Stanford; Sunni L Mumford; Lindsey A Sjaarda; Keewan Kim; Jessica R Zolton; Neil J Perkins; Enrique F Schisterman Journal: Paediatr Perinat Epidemiol Date: 2020-09-24 Impact factor: 3.103
Authors: Yasaman Zia; Jennifer Velloza; Lynda Oluoch; Richard Momanyi; Sarah Mbugua; John Njoroge; Stephen Gakuo; Edwin Mugo; Nicholas Thuo; Catherine Kiptinness; Njambi Njuguna; Kenneth Ngure; Nelly R Mugo; Renee Heffron Journal: Reprod Health Date: 2021-04-01 Impact factor: 3.223