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Pau-chung Chen - One of the best experts on this subject based on the ideXlab platform.
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prolonged menstrual cycles in female workers exposed to ethylene glycol ethers in the semiconductor manufacturing industry
Occupational and Environmental Medicine, 2005Co-Authors: Gong Yih Hsieh, Tsun-jen Cheng, Jung-der Wang, Pau-chung ChenAbstract:Background: It has been shown that female workers exposed to ethylene glycol ethers (EGEs) in the semiconductor industry have higher risks of spontaneous abortion, subfertility, and menstrual disturbances, and prolonged waiting Time to Pregnancy. Aims: to examine whether EGEs or other chemicals are associated with long menstrual cycles in female workers in the semiconductor manufacturing industry. Methods: Cross-sectional questionnaire survey during the annual health examination at a wafer manufacturing company in Taiwan in 1997. A three tiered exposure-assessment strategy was used to analyse the risk. A short menstrual cycle was defined to be a cycle less than 24 days and a long cycle to be more than 35 days. Results: There were 606 valid questionnaires from 473 workers in fabrication jobs and 133 in non-fabrication areas. Long menstrual cycles were associated with workers in fabrication areas compared to those in non-fabrication areas. Using workers in non-fabrication areas as referents, workers in photolithography and diffusion areas had higher risks for long menstrual cycles. Workers exposed to EGEs and isopropanol, and hydrofluoric acid, isopropanol, and phosphorous compounds also showed increased risks of a long menstrual cycle. Conclusions: Exposure to multiple chemicals, including EGEs in photolithography, might be associated with long menstrual cycles, and may play an important role in a prolonged Time to Pregnancy in the wafer manufacturing industry; however, the prevalence in the design, possible exposure misclassification, and chance should be considered.
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Prolonged Time to Pregnancy in Female Workers Exposed to Ethylene Glycol Ethers in Semiconductor Manufacturing
Epidemiology, 2002Co-Authors: Pau-chung Chen, Gong Yih Hsieh, Jung-der Wang, Tsun-jen ChengAbstract:Background. Previous research on reproductive effects of working in the semiconductor industry is limited and has produced conflicting results. Methods. This retrospective cohort study was designed to investigate the risk factors for female fertility in a wafer-manufacturing company of Taiwan in 1997. Waiting Time to Pregnancy and potential confounders were collected by face-to-face interview. Exposure was assessed by directors and senior engineers in manufacturing, administrative, and safety and health departments according to safety records, personnel records, and job histories from questionnaires, using a tiered exposure-assessment approach. Of a total 842 female workers, 720 (85.5%) participated. There were 292 pregnancies from 173 workers eligible for analysis. Relative fecundability (fecundability ratio, or FR) was calculated using Cox’s proportional hazard models to evaluate the effect of occupational exposure to ethylene glycol ethers on female fertility. Results. Waiting Time to Pregnancy of female workers in the photolithography area was longer than that of those in the nonfabrication area (FR = 0.77; 95% CI = 0.45–1.32), and those who were potentially exposed to ethylene glycol ethers showed longer Time to Pregnancy compared with those not exposed (FR = 0.59; 95% CI = 0.37–0.94). Conclusion. This study provides further evidence that ethylene glycol ethers may cause female subfertility.
Giuliana Trucco - One of the best experts on this subject based on the ideXlab platform.
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effectiveness of inpatient and outpatient treatment strategies for women with pelvic inflammatory disease results from the pelvic inflammatory disease evaluation and clinical health peach randomized trial
American Journal of Obstetrics and Gynecology, 2002Co-Authors: Roberta B Ness, Robert L Holley, Jeffrey Peipert, Hugh Randall, Steven J Sondheimer, Susan L Hendrix, Antonio J Amortegui, Davison E. Soper, Giuliana TruccoAbstract:OBJECTIVE: Pelvic inflammatory disease (PID) is a common and morbid intraperitoneal infection. Although most women with pelvic inflammatory disease are treated as outpatients, the effectiveness of this strategy remains unproven. STUDY DESIGN: We enrolled 831 women with clinical signs and symptoms of mild-to-moderate pelvic inflammatory disease into a multicenter randomized clinical trial of inpatient treatment initiated by intravenous cefoxitin and doxycycline versus outpatient treatment that consisted of a single intramuscular injection of cefoxitin and oral doxycycline. Long-term outcomes were Pregnancy rate, Time to Pregnancy, recurrence of pelvic inflammatory disease, chronic pelvic pain, and ectopic Pregnancy. RESULTS: Short-term clinical and microbiologic improvement were similar between women randomized to the inpatient and outpatient groups. After a mean follow-up period of 35 months, Pregnancy rates were nearly equal (42.0% for outpatients and 41.7% for inpatients). There were also no statistically significant differences between outpatient and inpatient groups in the outcome of Time to Pregnancy or in the proportion of women with pelvic inflammatory disease recurrence, chronic pelvic pain, or ectopic Pregnancy. CONCLUSION: Among women with mild-to-moderate pelvic inflammatory disease, there was no difference in reproductive outcomes between women randomized to inpatient treatment and those randomized to outpatient treatment.
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effectiveness of inpatient and outpatient treatment strategies for women with pelvic inflammatory disease results from the pelvic inflammatory disease evaluation and clinical health peach randomized trial
American Journal of Obstetrics and Gynecology, 2002Co-Authors: Roberta B Ness, Robert L Holley, Jeffrey Peipert, Hugh Randall, Steven J Sondheimer, Susan L Hendrix, Antonio J Amortegui, Davison E. Soper, Giuliana TruccoAbstract:Abstract Objective: Pelvic inflammatory disease (PID) is a common and morbid intraperitoneal infection. Although most women with pelvic inflammatory disease are treated as outpatients, the effectiveness of this strategy remains unproven. Study Design: We enrolled 831 women with clinical signs and symptoms of mild-to-moderate pelvic inflammatory disease into a multicenter randomized clinical trial of inpatient treatment initiated by intravenous cefoxitin and doxycycline versus outpatient treatment that consisted of a single intramuscular injection of cefoxitin and oral doxycycline. Long-term outcomes were Pregnancy rate, Time to Pregnancy, recurrence of pelvic inflammatory disease, chronic pelvic pain, and ectopic Pregnancy. Results: Short-term clinical and microbiologic improvement were similar between women randomized to the inpatient and outpatient groups. After a mean follow-up period of 35 months, Pregnancy rates were nearly equal (42.0% for outpatients and 41.7% for inpatients). There were also no statistically significant differences between outpatient and inpatient groups in the outcome of Time to Pregnancy or in the proportion of women with pelvic inflammatory disease recurrence, chronic pelvic pain, or ectopic Pregnancy. Conclusion: Among women with mild-to-moderate pelvic inflammatory disease, there was no difference in reproductive outcomes between women randomized to inpatient treatment and those randomized to outpatient treatment. (Am J Obstet Gynecol 2002;186:929-37.)
Roberta B Ness - One of the best experts on this subject based on the ideXlab platform.
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effectiveness of treatment strategies of some women with pelvic inflammatory disease a randomized trial
Obstetrics & Gynecology, 2005Co-Authors: Roberta B Ness, Jeffrey Peipert, Hugh Randall, Holly E Richter, Deborah B Nelson, Diane Schubeck, Gene S Mcneeley, Wayne Trout, Gail Trautmann, Debra C BassAbstract:Objective Among all women with pelvic inflammatory disease (PID), prevention of adverse reproductive consequences appears to be similarly achieved by outpatient treatment and inpatient treatment. We assessed whether outpatient is as effective as inpatient treatment in relevant age, race, and clinical subgroups of women with PID. Methods Women with clinical signs and symptoms of mild-to-moderate pelvic inflammatory disease (n = 831) were randomized into a multicenter trial of inpatient treatment, initially employing intravenous cefoxitin and doxycycline compared with outpatient treatment consisting of a single intramuscular injection of cefoxitin and oral doxycycline. Comparisons between treatment groups during a mean of 84 months of follow-up were made for pregnancies, live births, Time to Pregnancy, infertility, PID recurrence, chronic pelvic pain, and ectopic Pregnancy. Results Outpatient treatment assignment did not adversely impact the proportion of women having one or more pregnancies, live births, or ectopic pregnancies during follow-up; Time to Pregnancy; infertility; PID recurrence; or chronic pelvic pain among women of various races; with or without previous PID; with or without baseline Neisseria gonorrhoeae and/or Chlamydia trachomatis infection; and with or without high temperature/white blood cell count/pelvic tenderness score. This was true even in teenagers and women without a previous live birth. Ectopic pregnancies were more common in the outpatient than the inpatient treatment group, but because these were so rare, the difference did not reach statistical significance (5 versus 1, odds ratio 4.91, 95% confidence interval 0.57-42.25). Conclusion Among all women and subgroups of women with mild-to-moderate PID, there were no differences in reproductive outcomes after randomization to inpatient or outpatient treatment. Level of evidence I.
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effectiveness of inpatient and outpatient treatment strategies for women with pelvic inflammatory disease results from the pelvic inflammatory disease evaluation and clinical health peach randomized trial
American Journal of Obstetrics and Gynecology, 2002Co-Authors: Roberta B Ness, Robert L Holley, Jeffrey Peipert, Hugh Randall, Steven J Sondheimer, Susan L Hendrix, Antonio J Amortegui, Davison E. Soper, Giuliana TruccoAbstract:OBJECTIVE: Pelvic inflammatory disease (PID) is a common and morbid intraperitoneal infection. Although most women with pelvic inflammatory disease are treated as outpatients, the effectiveness of this strategy remains unproven. STUDY DESIGN: We enrolled 831 women with clinical signs and symptoms of mild-to-moderate pelvic inflammatory disease into a multicenter randomized clinical trial of inpatient treatment initiated by intravenous cefoxitin and doxycycline versus outpatient treatment that consisted of a single intramuscular injection of cefoxitin and oral doxycycline. Long-term outcomes were Pregnancy rate, Time to Pregnancy, recurrence of pelvic inflammatory disease, chronic pelvic pain, and ectopic Pregnancy. RESULTS: Short-term clinical and microbiologic improvement were similar between women randomized to the inpatient and outpatient groups. After a mean follow-up period of 35 months, Pregnancy rates were nearly equal (42.0% for outpatients and 41.7% for inpatients). There were also no statistically significant differences between outpatient and inpatient groups in the outcome of Time to Pregnancy or in the proportion of women with pelvic inflammatory disease recurrence, chronic pelvic pain, or ectopic Pregnancy. CONCLUSION: Among women with mild-to-moderate pelvic inflammatory disease, there was no difference in reproductive outcomes between women randomized to inpatient treatment and those randomized to outpatient treatment.
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effectiveness of inpatient and outpatient treatment strategies for women with pelvic inflammatory disease results from the pelvic inflammatory disease evaluation and clinical health peach randomized trial
American Journal of Obstetrics and Gynecology, 2002Co-Authors: Roberta B Ness, Robert L Holley, Jeffrey Peipert, Hugh Randall, Steven J Sondheimer, Susan L Hendrix, Antonio J Amortegui, Davison E. Soper, Giuliana TruccoAbstract:Abstract Objective: Pelvic inflammatory disease (PID) is a common and morbid intraperitoneal infection. Although most women with pelvic inflammatory disease are treated as outpatients, the effectiveness of this strategy remains unproven. Study Design: We enrolled 831 women with clinical signs and symptoms of mild-to-moderate pelvic inflammatory disease into a multicenter randomized clinical trial of inpatient treatment initiated by intravenous cefoxitin and doxycycline versus outpatient treatment that consisted of a single intramuscular injection of cefoxitin and oral doxycycline. Long-term outcomes were Pregnancy rate, Time to Pregnancy, recurrence of pelvic inflammatory disease, chronic pelvic pain, and ectopic Pregnancy. Results: Short-term clinical and microbiologic improvement were similar between women randomized to the inpatient and outpatient groups. After a mean follow-up period of 35 months, Pregnancy rates were nearly equal (42.0% for outpatients and 41.7% for inpatients). There were also no statistically significant differences between outpatient and inpatient groups in the outcome of Time to Pregnancy or in the proportion of women with pelvic inflammatory disease recurrence, chronic pelvic pain, or ectopic Pregnancy. Conclusion: Among women with mild-to-moderate pelvic inflammatory disease, there was no difference in reproductive outcomes between women randomized to inpatient treatment and those randomized to outpatient treatment. (Am J Obstet Gynecol 2002;186:929-37.)
Tsun-jen Cheng - One of the best experts on this subject based on the ideXlab platform.
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prolonged menstrual cycles in female workers exposed to ethylene glycol ethers in the semiconductor manufacturing industry
Occupational and Environmental Medicine, 2005Co-Authors: Gong Yih Hsieh, Tsun-jen Cheng, Jung-der Wang, Pau-chung ChenAbstract:Background: It has been shown that female workers exposed to ethylene glycol ethers (EGEs) in the semiconductor industry have higher risks of spontaneous abortion, subfertility, and menstrual disturbances, and prolonged waiting Time to Pregnancy. Aims: to examine whether EGEs or other chemicals are associated with long menstrual cycles in female workers in the semiconductor manufacturing industry. Methods: Cross-sectional questionnaire survey during the annual health examination at a wafer manufacturing company in Taiwan in 1997. A three tiered exposure-assessment strategy was used to analyse the risk. A short menstrual cycle was defined to be a cycle less than 24 days and a long cycle to be more than 35 days. Results: There were 606 valid questionnaires from 473 workers in fabrication jobs and 133 in non-fabrication areas. Long menstrual cycles were associated with workers in fabrication areas compared to those in non-fabrication areas. Using workers in non-fabrication areas as referents, workers in photolithography and diffusion areas had higher risks for long menstrual cycles. Workers exposed to EGEs and isopropanol, and hydrofluoric acid, isopropanol, and phosphorous compounds also showed increased risks of a long menstrual cycle. Conclusions: Exposure to multiple chemicals, including EGEs in photolithography, might be associated with long menstrual cycles, and may play an important role in a prolonged Time to Pregnancy in the wafer manufacturing industry; however, the prevalence in the design, possible exposure misclassification, and chance should be considered.
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Prolonged Time to Pregnancy in Female Workers Exposed to Ethylene Glycol Ethers in Semiconductor Manufacturing
Epidemiology, 2002Co-Authors: Pau-chung Chen, Gong Yih Hsieh, Jung-der Wang, Tsun-jen ChengAbstract:Background. Previous research on reproductive effects of working in the semiconductor industry is limited and has produced conflicting results. Methods. This retrospective cohort study was designed to investigate the risk factors for female fertility in a wafer-manufacturing company of Taiwan in 1997. Waiting Time to Pregnancy and potential confounders were collected by face-to-face interview. Exposure was assessed by directors and senior engineers in manufacturing, administrative, and safety and health departments according to safety records, personnel records, and job histories from questionnaires, using a tiered exposure-assessment approach. Of a total 842 female workers, 720 (85.5%) participated. There were 292 pregnancies from 173 workers eligible for analysis. Relative fecundability (fecundability ratio, or FR) was calculated using Cox’s proportional hazard models to evaluate the effect of occupational exposure to ethylene glycol ethers on female fertility. Results. Waiting Time to Pregnancy of female workers in the photolithography area was longer than that of those in the nonfabrication area (FR = 0.77; 95% CI = 0.45–1.32), and those who were potentially exposed to ethylene glycol ethers showed longer Time to Pregnancy compared with those not exposed (FR = 0.59; 95% CI = 0.37–0.94). Conclusion. This study provides further evidence that ethylene glycol ethers may cause female subfertility.
Elizabeth E. Hatch - One of the best experts on this subject based on the ideXlab platform.
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a prospective study of treatments for cervical intraepithelial neoplasia and fecundability
American Journal of Obstetrics and Gynecology, 2020Co-Authors: Lauren A. Wise, Ellen M. Mikkelsen, Amelia K. Wesselink, Kristen A Hahn, Sydney K Willis, Holly Michelle Crowe, Rebecca B Perkins, Alexandra M Klann, Elizabeth E. HatchAbstract:Background Treatments for cervical intraepithelial neoplasia remove precancerous cells from the cervix by excising or ablating the transformation zone. Most studies show no association between cervical intraepithelial neoplasia treatments and fertility outcomes. However, only 2 studies have examined Time to Pregnancy, both using retrospective study designs, with 1 study showing no association and the other showing a 2-fold increased risk of infertility (Time to Pregnancy >12 months) following excisional or ablative treatment. Objective We examined the association between cervical intraepithelial neoplasia treatments and fecundability. Materials and Methods We analyzed data from Pregnancy Study Online (PRESto), a prospective cohort study of North American Pregnancy planners enrolled during 2013−2019. At baseline, women reported whether they ever had an abnormal Papanicolaou test result, the number of abnormal Papanicolaou test results, and their age at first abnormal Papanicolaou test result. They also reported whether they underwent diagnostic (colposcopy) or treatment (excisional or ablative) procedures, and their age at each procedure. We restricted analyses to 8017 women with 6 or fewer cycles of attempt Time at enrollment who reported receiving a Papanicolaou test in the previous 3 years. We estimated fecundability ratios and 95% confidence intervals using proportional probabilities models adjusted for sociodemographics, healthcare use, smoking, number of sexual partners, history of sexually transmitted infections, and human papillomavirus vaccination. Results A history of abnormal Papanicolaou test results showed little association with fecundability (fecundability ratio, 1.00; 95% confidence interval, 0.95−1.06). Likewise, receipt of colposcopy or treatment procedures, and Time since treatment were not materially associated with fecundability. Results were similar when stratified by age and smoking status. Conclusion We observed no appreciable association of self-reported history of abnormal Papanicolaou test results, colposcopy, treatments for cervical intraepithelial neoplasia, or recency of treatment with fecundability. These results agree with the majority of previous studies in indicating little effect of cervical intraepithelial neoplasia treatments on future fertility.
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exposure to tetrachloroethylene contaminated drinking water and Time to Pregnancy
Environmental Research, 2018Co-Authors: Amelia K. Wesselink, Kenneth J. Rothman, Elizabeth E. Hatch, Lauren A. Wise, Veronica M Vieira, Ann AschengrauAbstract:Abstract Background The synthetic solvent tetrachloroethylene (PCE), commonly used in dry cleaning operations, is a human neurotoxicant and carcinogen. However, its effect on reproduction is poorly understood, as prior studies have been limited to small occupational cohorts. We examined the association between PCE exposure from contamination of the public drinking water supply and Time-to-Pregnancy (TTP) in a cohort of mothers from Cape Cod, Massachusetts. Methods The Cape Cod Family Health Study is a retrospective cohort study designed to examine the reproductive and developmental health effects of exposure to PCE-contaminated drinking water. Our analysis included 1565 women who reported 3826 planned pregnancies from 1949 to 1990. Women completed self-administered questionnaires that ascertained TTP for each of her pregnancies, regardless of the outcome, as well as residential history and demographic information. We utilized EPANET water distribution system modeling software and a leaching and transport model to assess PCE exposure for each Pregnancy. We used log-binomial regression models to estimate relative risks (RR) and 95% confidence intervals (CI), adjusting for potential confounders. We performed a probabilistic bias analysis to examine the effect of outcome misclassification on our results. Results Any cumulative PCE exposure before Pregnancy was associated with a 15% reduction in risk of TTP > 12 months (RR = 0.85, 95% CI: 0.70, 1.03). However, women with the highest average monthly PCE exposure around the Time of the Pregnancy attempt (≥ 2.5 g) had increased risk of TTP > 12 months (RR = 1.36, 95% CI: 1.06, 1.76). Conclusions We found little evidence for long-term, cumulative adverse effects of PCE exposure on TTP, but high levels of PCE exposure around the Time of the Pregnancy attempt were associated with longer TTP. These associations may be underestimated due to the exclusion of unsuccessful Pregnancy attempts from our study population, and may be biased by outcome and exposure misclassification given the long-term recall of TTP and use of a leaching and transport model to estimate PCE exposure.
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Brief Report:Cesarean Delivery and Subsequent Fecundability
Epidemiology, 2016Co-Authors: Rose G. Radin, Ellen M. Mikkelsen, Kenneth J. Rothman, Elizabeth E. Hatch, Henrik Toft Sørensen, Anders H. Riis, Wendy Kuohung, Lauren A. WiseAbstract:Background: Studies have shown that cesarean delivery is associated with fewer subsequent births relative to vaginal delivery, but it is unclear whether confounding by Pregnancy intention or indication for surgery explained these results. We evaluated the association between cesarean delivery and subsequent fecundability among 910 primiparous women after singleton live birth. Methods: In a cohort of Danish women planning Pregnancy (2007–2012), obstetrical history was obtained via registry linkage; Time-to-Pregnancy and covariate data were collected via questionnaire. Fecundability ratios (FRs) and 95% confidence intervals (CIs) were adjusted for potential confounders. Results: Relative to spontaneous vaginal delivery, emergency cesarean delivery with cephalic presentation showed little association with fecundability (FR = 1.0, 95% CI = 0.83, 1.3), but cesarean delivery with breech presentation (FR = 0.72, 95% CI = 0.53, 0.97) and planned cesarean delivery with cephalic presentation (FR = 0.51, 95% CI = 0.25, 1.0) were associated with reduced fecundability. Conclusions: The cesarean–fecundability association varied by previous fetal presentation and emergency status.
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maternal recall error in retrospectively reported Time to Pregnancy an assessment and bias analysis
Paediatric and Perinatal Epidemiology, 2015Co-Authors: Rose G. Radin, Ellen M. Mikkelsen, Kenneth J. Rothman, Elizabeth E. Hatch, Henrik Toft Sørensen, Anders H. Riis, Matthew P FoxAbstract:Background Epidemiologic studies of fecundability often use retrospectively measured Time-to-Pregnancy (TTP), thereby introducing potential for recall error. Little is known about how recall error affects the bias and precision of the fecundability odds ratio (FOR) in such studies. Methods Using data from the Danish Snart-Gravid Study (2007–12), we quantified error for TTP recalled in the first trimester of Pregnancy relative to prospectively measured TTP among 421 women who enrolled at the start of their Pregnancy attempt and became pregnant within 12 months. We defined recall error as retrospectively measured TTP minus prospectively measured TTP. Using linear regression, we assessed mean differences in recall error by maternal characteristics. We evaluated the resulting bias in the FOR and 95% confidence interval (CI) using simulation analyses that compared corrected and uncorrected retrospectively measured TTP values. Results Recall error (mean = −0.11 months, 95% CI −0.25, 0.04) was not appreciably associated with maternal age, gravidity, or recent oral contraceptive use. Women with TTP > 2 months were more likely to underestimate their TTP than women with TTP ≤ 2 months (unadjusted mean difference in error: −0.40 months, 95% CI −0.71, −0.09). FORs of recent oral contraceptive use calculated from prospectively measured, retrospectively measured, and corrected TTPs were 0.82 (95% CI 0.67, 0.99), 0.74 (95% CI 0.61, 0.90), and 0.77 (95% CI 0.62, 0.96), respectively. Conclusions Recall error was small on average among Pregnancy planners who became pregnant within 12 months. Recall error biased the FOR of recent oral contraceptive use away from the null by 10%. Quantitative bias analysis of the FOR can help researchers quantify the bias from recall error.
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an internet based prospective study of body size and Time to Pregnancy
Human Reproduction, 2010Co-Authors: Lauren A. Wise, Ellen M. Mikkelsen, Kenneth J. Rothman, Henrik Toft Sørensen, Anders H. Riis, Elizabeth E. HatchAbstract:BACKGROUND: Recent studies have shown that both female and male obesity may delay Time-to-Pregnancy (TTP). Little is known about central adiposity or weight gain and fecundability in women. METHODS: We examined the association between anthropometric factors and TTP among I65I Danish women participating in an inter-net-based prospective cohort study of Pregnancy planners (2007―2008). We categorized body mass index (BMI = kg/m 2 ) as underweight (<20), normal weight (20-24), overweight (25-29), obese (30-34) and very obese (≥35). We used discrete-Time Cox regression to estimate fecundability ratios (FRs) and 95% confidence intervals (CI), controlling for potential confounders. RESULTS: We found longer TTPs for overweight (FR = 0.83, 95% CI = 0.70―I.00), obese (FR = 0.75, 95% CI = 0.58-0.97), and very obese (FR = 0.61, 95% CI = 0.42―0.88) women, compared with normal weight women. After further control for waist circumference, FRs for overweight, obese, and very obese women were 0.72 (95% CI = 0.58―0.90), 0.60 (95% CI = 0.42-0.85) and 0.48 (95% CI = 0.3I-0.74), respectively. Underweight was associated with reduced fecundability among nulliparous women (FR = 0.82, 95% CI = 0.63- I.06) and increased fecundability among parous women (FR = 1.61, 95% CI = 1.08-2.39). Male BMI was not materially associated with TTP after control for female BMI. Compared with women who maintained a stable weight since age I7 (―5 to 4 kg), women who gained ≥ 15 kg had longer TTPs (FR = 0.72, 95% CI = 0.59-0.88) after adjustment for BMI at age I7. Associations of waist circumference and waist-to-hip ratio with TTP depended on adjustment for female BMI: null associations were observed before adjustment for BMI and weakly positive associations were observed after adjustment for BMI. CONCLUSIONS: Our results confirm previous studies showing reduced fertility in overweight and obese women. The association between underweight and fecundability varied by parity.
