Pre-pregnancy fast food and fruit intake is associated with time to pregnancy
- 4 May 2018
- journal article
- research article
- Published by Oxford University Press (OUP) in Human Reproduction
- Vol. 33 (6), 1063-1070
- https://doi.org/10.1093/humrep/dey079
Abstract
Is preconception dietary intake associated with reduced fecundity as measured by a longer time to pregnancy (TTP)? Lower intake of fruit and higher intake of fast food in the preconception period were both associated with a longer TTP. Several lifestyle factors, such as smoking and obesity, have consistently been associated with a longer TTP or infertility, but the role of preconception diet in women remains poorly studied. Healthier foods or dietary patterns have been associated with improved fertility, however, these studies focused on women already diagnosed with or receiving treatments for infertility, rather than in the general population. This was a multi-center pregnancy-based cohort study of 5628 nulliparous women with low-risk singleton pregnancies who participated in the Screening for Pregnancy Endpoints (SCOPE) study. A total of 5598 women were included. Data on retrospectively reported TTP and preconception dietary intake were collected during the first antenatal study visit (14–16 weeks’ gestation). Dietary information for the 1 month prior to conception was obtained from food frequency questions for fruit, green leafy vegetables, fish and fast foods, by a research midwife. Use of any fertility treatments associated with the current pregnancy was documented (yes, n = 340, no, n = 5258). Accelerated failure time models with log normal distribution were conducted to estimate time ratios (TR) and 95% CIs. The impact of differences in dietary intake on infertility (TTP >12 months) was compared using a generalized linear model (Poisson distribution) with robust variance estimates, with resulting relative risks (RR) and 95% CIs. All analyses were controlled for a range of maternal and paternal confounders. Sensitivity analyses were conducted to explore potential biases common to TTP studies. Lower intakes of fruit and higher intakes of fast food were both associated with modest increases in TTP and infertility. Absolute differences between the lowest and highest categories of intake for fruit and fast food were in the order of 0.6–0.9 months for TTP and 4–8% for infertility. Compared with women who consumed fruit ≥3 times/day, the adjusted effects of consuming fruit ≥1–Ptrend = 0.007). Similarly, compared with women who consumed fast food ≥4 times/week, the adjusted effects of consuming fast food ≥2–0–Ptrend Ptrend = 0.043). Similarly, compared with women who consumed fast food ≥4 times/week, the adjusted effects of consuming fast food ≥2–0–Ptrend <0.001). Pre-pregnancy intake of green leafy vegetables or fish were not associated with TTP or infertility. Estimates remained stable across a range of sensitivity analyses. Collection of dietary data relied on retrospective recall and evaluated a limited range of foods. Paternal dietary data was not collected and the potential for residual confounding cannot be eliminated. Compared to prospective TTP studies, retrospective TTP studies are prone to a number of potential sources of bias. These findings underscore the importance of considering preconception diet for fecundity outcomes and preconception guidance. Further research is needed assessing a broader range of foods and food groups in the preconception period. The SCOPE database is provided and maintained by MedSciNet AB (http://medscinet.com). The Australian SCOPE study was funded by the Premier’s Science and Research Fund, South Australian Government (http://www.dfeest.sa.gov.au/science-research/premiers-research-and-industry-fund). The New Zealand SCOPE study was funded by the New Enterprise Research Fund, Foundation for Research Science and Technology; Health Research Council (04/198); Evelyn Bond Fund, Auckland District Health Board Charitable Trust. The Irish SCOPE study was funded by the Health Research Board of Ireland (CSA/2007/2; http://www.hrb.ie). The UK SCOPE study was funded by National Health Service NEAT Grant (Neat Grant FSD025), Biotechnology and Biological Sciences Research council (www.bbsrc.ac.uk/funding; GT084) and University of Manchester Proof of Concept Funding (University of Manchester); Guy’s and St. Thomas’ Charity (King’s College London) and Tommy’s charity (http://www.tommys.org/; King’s College London and University of Manchester); and Cerebra UK (www.cerebra.org.uk; University of Leeds). L.E.G. is supported by an Australian National Health and Medical Research Council (NHMRC) Early Career Fellowship (ID 1070421). L.J.M. is supported by a SACVRDP Fellowship; a program collaboratively funded by the National Heart Foundation, the South Australian Department of Health and the South Australian Health and Medical Research Institute. L.C.K. is supported by a Science Foundation Ireland Program Grant for INFANT (12/RC/2272). C.T.R. was supported by a National Health and Medical Research Council (NHMRC) Senior Research Fellowship (GNT1020749). There are no conflicts of interest to declare. Not applicable.Keywords
Funding Information
- New Enterprise Research Fund, Foundation for Research Science and Technology (04/198)
- Health Research Board of Ireland (CSA/2007/2)
- National Health Service NEAT (FSD025)
- Biotechnology and Biological Sciences Research Council (GT084)
- Australian National Health and Medical Research Council (NHMRC) (1070421)
- National Heart Foundation
- Science Foundation Ireland Program Grant for INFANT (12/RC/2272)
This publication has 36 references indexed in Scilit:
- Clinical risk prediction for pre-eclampsia in nulliparous women: development of model in international prospective cohortBMJ, 2011
- The preconception Mediterranean dietary pattern in couples undergoing in vitro fertilization/intracytoplasmic sperm injection treatment increases the chance of pregnancyFertility and Sterility, 2010
- Risk factors for small‐for‐gestational‐age infants by customised birthweight centiles: data from an international prospective cohort studyBJOG: An International Journal of Obstetrics and Gynaecology, 2010
- Spontaneous preterm birth and small for gestational age infants in women who stop smoking early in pregnancy: prospective cohort studyBMJ, 2009
- Metabolic Syndrome and Incident DiabetesDiabetes Care, 2008
- A prospective study of dietary carbohydrate quantity and quality in relation to risk of ovulatory infertilityEuropean Journal of Clinical Nutrition, 2007
- Obesity and time to pregnancyHuman Reproduction, 2006
- Eating at fast-food restaurants is associated with dietary intake, demographic, psychosocial and behavioural factors among African Americans in North CarolinaPublic Health Nutrition, 2004
- Fast food restaurant use among women in the Pound of Prevention study: dietary, behavioral and demographic correlatesInternational Journal of Obesity, 2000
- Does Moderate Alcohol Intake Reduce Fecundability? A European Multicenter Study on Infertility and SubfecundityAlcohol: Clinical and Experimental Research, 1997