See Ling Loy1, Chee Wai Ku2, Ada En Qi Lai3, Xin Hui Choo3, Angela Hui Min Ho3, Yin Bun Cheung4, Keith M Godfrey5, Yap-Seng Chong6, Peter D Gluckman7, Lynette Pei-Chi Shek8, Kok Hian Tan9, Fabian Kok Peng Yap10, Shiao-Yng Chan11, Jerry Kok Yen Chan12. 1. Department of Reproductive Medicine, KK Women's and Children's Hospital, Singapore; Duke-NUS Medical School, Singapore; Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A∗STAR), Singapore. Electronic address: loy.see.ling@kkh.com.sg. 2. Duke-NUS Medical School, Singapore; Department of Obstetrics and Gynaecology, KK Women's and Children's Hospital, Singapore. 3. Yong Loo Lin School of Medicine, National University of Singapore, National University Health System, Singapore. 4. Center for Quantitative Medicine, Duke-NUS Medical School, Singapore; Tampere Center for Child Health Research, University of Tampere and Tampere University Hospital, Tampere, Finland. 5. Medical Research Council Lifecourse Epidemiology Unit, University of Southampton, Southhampton, United Kingdom; National Institute for Health Research Southampton Biomedical Research Centre, University of Southampton and University Hospital Southampton National Health Service Foundation Trust, Southampton, United Kingdom. 6. Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A∗STAR), Singapore; Yong Loo Lin School of Medicine, National University of Singapore, National University Health System, Singapore. 7. Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A∗STAR), Singapore; Liggins Institute, University of Auckland, Auckland, New Zealand. 8. Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A∗STAR), Singapore; Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, National University Health System, Singapore; Khoo Teck Puat-National University Children's Medical Institute, National University Hospital, National University Health System, Singapore. 9. Duke-NUS Medical School, Singapore; Department of Maternal Fetal Medicine, KK Women's and Children's Hospital, Singapore. 10. Duke-NUS Medical School, Singapore; Department of Paediatrics, KK Women's and Children's Hospital, Singapore; Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore. 11. Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A∗STAR), Singapore; Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, National University Health System, Singapore. 12. Department of Reproductive Medicine, KK Women's and Children's Hospital, Singapore; Duke-NUS Medical School, Singapore.
Abstract
OBJECTIVE: To examine the association between plasma glycemia in women attempting to conceive and fecundability, as measured by time to pregnancy. DESIGN: Prospective preconception population-based study. SETTING: Hospital. PATIENT(S): Asian preconception women, 18-45 years old, attempting conception for ≤12 cycles at study entry. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): We ascertained time to pregnancy within a year of glycemic assessment in menstrual cycles. We estimated fecundability ratios (FRs) and 95% confidence intervals using discrete-time proportional hazards models, adjusting for age, ethnicity, education, body mass index, and cycle regularity and accounting for left truncation and right censoring. RESULT(S): We studied a population sample of 766 women from the Singapore Preconception Study of Long-Term Maternal and Child Outcomes prospective cohort. Compared with women with normoglycemia, women with dysglycemia (prediabetes and diabetes, defined by the American Diabetes Association) had a lower FR (0.56). Compared with the respective lowest quintiles, women in the highest quintile of fasting glucose (≥5.1 mmol/L) had an FR of 0.60, while women in the highest 2-hour postload glucose quintile (≥6.9 mmol/L) had an FR of 0.66. Overall, the FRs decreased generally across the range of fasting and 2-hour plasma glucose. Glycated hemoglobin was not associated with fecundability. CONCLUSION(S): Increasing preconception plasma glucose is associated with reduced fecundability, even within the normal range of glucose concentrations. CLINICAL TRIAL REGISTRATION NUMBER: NCT03531658.
OBJECTIVE: To examine the association between plasma glycemia in women attempting to conceive and fecundability, as measured by time to pregnancy. DESIGN: Prospective preconception population-based study. SETTING: Hospital. PATIENT(S): Asian preconception women, 18-45 years old, attempting conception for ≤12 cycles at study entry. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): We ascertained time to pregnancy within a year of glycemic assessment in menstrual cycles. We estimated fecundability ratios (FRs) and 95% confidence intervals using discrete-time proportional hazards models, adjusting for age, ethnicity, education, body mass index, and cycle regularity and accounting for left truncation and right censoring. RESULT(S): We studied a population sample of 766 women from the Singapore Preconception Study of Long-Term Maternal and Child Outcomes prospective cohort. Compared with women with normoglycemia, women with dysglycemia (prediabetes and diabetes, defined by the American Diabetes Association) had a lower FR (0.56). Compared with the respective lowest quintiles, women in the highest quintile of fasting glucose (≥5.1 mmol/L) had an FR of 0.60, while women in the highest 2-hour postload glucose quintile (≥6.9 mmol/L) had an FR of 0.66. Overall, the FRs decreased generally across the range of fasting and 2-hour plasma glucose. Glycated hemoglobin was not associated with fecundability. CONCLUSION(S): Increasing preconception plasma glucose is associated with reduced fecundability, even within the normal range of glucose concentrations. CLINICAL TRIAL REGISTRATION NUMBER: NCT03531658.
Authors: S L Loy; Y B Cheung; S E Soh; S Ng; M T Tint; I M Aris; J Y Bernard; Y S Chong; K M Godfrey; L P Shek; K H Tan; Y S Lee; H H Tan; B S M Chern; N Lek; F Yap; S Y Chan; C Chi; J K Y Chan Journal: Hum Reprod Date: 2018-11-01 Impact factor: 6.918
Authors: Tuck Seng Cheng; See Ling Loy; Yin Bun Cheung; Keith M Godfrey; Peter D Gluckman; Kenneth Kwek; Seang Mei Saw; Yap-Seng Chong; Yung Seng Lee; Fabian Yap; Jerry Kok Yen Chan; Ngee Lek Journal: Prev Sci Date: 2016-11
Authors: Lihua Huang; See Ling Loy; Wei-Qing Chen; Johan G Eriksson; Yap Seng Chong; Zhongwei Huang; Jerry Kok Yen Chan; Tien Yin Wong; Michael Kramer; Cuilin Zhang; Ling-Jun Li Journal: Hum Reprod Date: 2021-10-18 Impact factor: 6.918
Authors: Shan Xuan Lim; See Ling Loy; Marjorelee T Colega; Jun Shi Lai; Keith M Godfrey; Yung Seng Lee; Kok Hian Tan; Fabian Yap; Lynette Pei-Chi Shek; Yap Seng Chong; Johan G Eriksson; Jerry Kok Yen Chan; Shiao-Yng Chan; Mary Foong-Fong Chong Journal: Am J Clin Nutr Date: 2022-02-09 Impact factor: 8.472