J A Grieger1,2, L E Grzeskowiak1,2, L G Smithers1,3, T Bianco-Miotto1,4, S Y Leemaqz1,2, P Andraweera1,2, L Poston5, L M McCowan6, L C Kenny7, J Myers8, J J Walker9, R J Norman1,10, G A Dekker1,11, C T Roberts1,2. 1. Robinson Research Institute, University of Adelaide, North Adelaide, South Australia, Australia. 2. Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia. 3. School of Public Health, University of Adelaide, Adelaide, South Australia, Australia. 4. Waite Research Institute, School of Agriculture, Food and Wine, University of Adelaide, Adelaide, South Australia, Australia. 5. Department of Women and Children's Health, King's College London, St Thomas' Hospital, Westminster Bridge, London, UK. 6. Department of Obstetrics and Gynaecology, University of Auckland, Auckland, New Zealand. 7. Faculty of Health & Life Sciences, University of Liverpool, Liverpool, UK. 8. Maternal and Fetal Health Research Centre, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK. 9. Obstetrics and Gynaecology Section, Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, UK. 10. Fertility SA, Adelaide, South Australia, Australia. 11. Women and Children's Division, Lyell McEwin Hospital, University of Adelaide, Adelaide, South Australia, Australia.
Abstract
OBJECTIVE: To determine: (1) the association between metabolic syndrome (MetS), time to pregnancy (TTP), and infertility; (2) associations between individual and an increasing number of MetS components, TTP, and infertility; and (3) whether these relationships differ by body mass index (BMI < 30 kg/m2 versus BMI ≥ 30 kg/m2 ). DESIGN: Retrospective cohort study. SETTING: Multiple centres (in Australia, Ireland, New Zealand, and the UK). POPULATION: Five thousand five hundred and nineteen low-risk nulliparous pregnant women. METHODS: Data on retrospectively reported TTP (number of months to conceive) and a blood sample to assess metabolic health were collected between 14 and 16 weeks of gestation. MetS was defined according to the International Diabetes Federation criteria. Accelerated failure time models with log-normal distribution were conducted to estimate time ratios (TRs) and 95% CIs. Differences in MetS on infertility (TTP > 12 months) were compared using a generalised linear model (Poisson distribution) with robust variance estimates (relative risks, RRs; 95% CIs). All analyses (entire cohort and split by BMI) were controlled for a range of maternal and paternal confounding factors. MAIN OUTCOME MEASURES: Time to pregnancy and infertility. RESULTS: Of the 5519 women included, 12.4% (n = 684) had MetS. Compared with women without MetS, women with MetS had a longer TTP (adjusted TR 1.30; 95% CI 1.15-1.46), which was similar in women who were obese and in women who were not obese. Marginal estimates for median TTP in women with MetS versus without MetS was 3.1 months (3.0-3.3 months) versus 4.1 months (3.6-4.5 months), respectively. Women with MetS were at a 62% greater risk for infertility and were at a greater risk for infertility whether they were obese (adjusted RR 1.62; 95% CI 1.15-2.29) or not (adjusted RR 1.73; 95% CI 1.33-2.23). Reduced high-density lipoprotein cholesterol (HDL-C) and raised triglycerides (TGs) were the main individual components associated with risk for infertility. CONCLUSION: Metabolic syndrome is associated with longer TTP and infertility, independent of obesity. Additional studies, before pregnancy, are required to support our findings and to determine the applicability of which combinations of metabolic abnormalities pose the greatest risk to delayed fertility, or whether individual components are amenable to modification. TWEETABLE ABSTRACT: Metabolic syndrome is associated with longer time to pregnancy and infertility, independent of obesity.
OBJECTIVE: To determine: (1) the association between metabolic syndrome (MetS), time to pregnancy (TTP), and infertility; (2) associations between individual and an increasing number of MetS components, TTP, and infertility; and (3) whether these relationships differ by body mass index (BMI < 30 kg/m2 versus BMI ≥ 30 kg/m2 ). DESIGN: Retrospective cohort study. SETTING: Multiple centres (in Australia, Ireland, New Zealand, and the UK). POPULATION: Five thousand five hundred and nineteen low-risk nulliparous pregnant women. METHODS: Data on retrospectively reported TTP (number of months to conceive) and a blood sample to assess metabolic health were collected between 14 and 16 weeks of gestation. MetS was defined according to the International Diabetes Federation criteria. Accelerated failure time models with log-normal distribution were conducted to estimate time ratios (TRs) and 95% CIs. Differences in MetS on infertility (TTP > 12 months) were compared using a generalised linear model (Poisson distribution) with robust variance estimates (relative risks, RRs; 95% CIs). All analyses (entire cohort and split by BMI) were controlled for a range of maternal and paternal confounding factors. MAIN OUTCOME MEASURES: Time to pregnancy and infertility. RESULTS: Of the 5519 women included, 12.4% (n = 684) had MetS. Compared with women without MetS, women with MetS had a longer TTP (adjusted TR 1.30; 95% CI 1.15-1.46), which was similar in women who were obese and in women who were not obese. Marginal estimates for median TTP in women with MetS versus without MetS was 3.1 months (3.0-3.3 months) versus 4.1 months (3.6-4.5 months), respectively. Women with MetS were at a 62% greater risk for infertility and were at a greater risk for infertility whether they were obese (adjusted RR 1.62; 95% CI 1.15-2.29) or not (adjusted RR 1.73; 95% CI 1.33-2.23). Reduced high-density lipoprotein cholesterol (HDL-C) and raised triglycerides (TGs) were the main individual components associated with risk for infertility. CONCLUSION: Metabolic syndrome is associated with longer TTP and infertility, independent of obesity. Additional studies, before pregnancy, are required to support our findings and to determine the applicability of which combinations of metabolic abnormalities pose the greatest risk to delayed fertility, or whether individual components are amenable to modification. TWEETABLE ABSTRACT: Metabolic syndrome is associated with longer time to pregnancy and infertility, independent of obesity.
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: See Ling Loy; Chee Wai Ku; Ada En Qi Lai; Xin Hui Choo; Angela Hui Min Ho; Yin Bun Cheung; Keith M Godfrey; Yap-Seng Chong; Peter D Gluckman; Lynette Pei-Chi Shek; Kok Hian Tan; Fabian Kok Peng Yap; Shiao-Yng Chan; Jerry Kok Yen Chan Journal: Fertil Steril Date: 2020-10-15 Impact factor: 7.329