Identifying the Peak Day of Fertility

Epidemiologic evidence indicates that in-utero exposures to environmental chemicals may have both short- and long-term health effects. In order to properly assess exposures, the estimated day of ovulation (EDO) must be identified prospectively so that targeted exposure assessment during relevant developmental windows can occur. One method of identifying the EDO is to monitor changes in basal body temperature (BBT) and cervical mucus secretions. While other methods exist, their daily use is costly. The aims of this ongoing study are to 1) determine the feasibility of teaching women to identify their EDO without practitioner guidance and 2) compare the acceptability and actual use of monitoring cervical secretions alone, or in complement with recording BBT. One hundred women ages 18-44 who are not yet pregnant but are planning pregnancy are being recruited using population-based procedures similar to the National Children's Study, but in different neighborhood segments. Women who consent to participate are mailed six fertility charts, six 1-page monthly exposure questionnaires and a 3-page educational brochure. An online questionnaire that ascertains demographics and key environmental exposures (past and present) is administered at enrollment. Recruitment began in November 2008, 16 participants are currently enrolled (of 41 total inquiries). Statistical analyses are pending the recruitment of more participants and the receipt of monthly fertility charts. However, preliminary results indicate that women can properly identify their EDO using this method, given that 25% of our enrollees became pregnant after joining the study and beginning to monitor their fertility signs.