Infertility, Infertility Treatment, and Fetal Growth Restriction
- 1 December 2007
- journal article
- research article
- Published by Ovid Technologies (Wolters Kluwer Health) in Obstetrics & Gynecology
- Vol. 110 (6), 1326-1334
- https://doi.org/10.1097/01.aog.0000290330.80256.97
Abstract
OBJECTIVE: To examine the association between infertility, with or without treatment, and fetal growth, as well as perinatal and infant mortality. METHODS: From the Danish National Birth Cohort (1997–2003), we identified 51,041 singletons born of fertile couples (time to pregnancy 12 months or less), 5,787 born of infertile couples conceiving naturally (time to pregnancy more than 12 months), and 4,317 born after treatment. We defined small for gestational age (SGA) as the lowest 5% of birth weight by sex and gestational age. RESULTS: Crude estimates suggested an increased risk of perinatal mortality and SGA among infertile couples (treated and untreated), but the odds ratios (ORs) of perinatal mortality among infertile couples were attenuated after adjustment for maternal age and body mass index (1.32, 95% confidence interval [CI] 0.95–1.84 among untreated and 1.26, 95% CI 0.86–1.85 among treated couples). The elevated risk of SGA among infertile couples persisted after adjustment for maternal age, parity, and smoking (OR 1.24, 95% CI 1.10–1.40 among untreated, and OR 1.40, 95% CI 1.23–1.60 among treated). The risk of SGA increased with time to pregnancy, and a longer time to pregnancy was associated with a small reduction in birth weight across the whole distribution. CONCLUSION: The increased risk of SGA observed among infertile couples with or without infertility treatment suggests that infertility may be a risk factor for intrauterine growth restriction. Treatment per se may have little effect on fetal growth. A small-to-moderate increased risk of perinatal mortality in infertile couples cannot be ruled out due to the small number of cases. LEVEL OF EVIDENCE: IIKeywords
This publication has 29 references indexed in Scilit:
- Infertility, infertility treatment and twinning: the Danish National Birth CohortHuman Reproduction, 2007
- Infertility, infertility treatment, and congenital malformations: Danish national birth cohortBMJ, 2006
- Does Low Participation in Cohort Studies Induce Bias?Epidemiology, 2006
- Is conception delay a risk factor for reduced gestation or birthweight?Paediatric and Perinatal Epidemiology, 2006
- Intrauterine growth restrictionCurrent Opinion in Obstetrics and Gynecology, 2005
- Subfecundity and neonatal mortality: longitudinal study within the Danish national birth cohortBMJ, 2005
- Shift work, duration of pregnancy, and birth weight:: The National Birth Cohort in DenmarkAmerican Journal of Obstetrics and Gynecology, 2004
- Workshop Summary: Fetal Growth: Its Regulation and DisordersPEDIATRICS, 1997
- Bias in Studies of Preterm and Postterm Delivery Due to Ultrasound Assessment of Gestational AgeEpidemiology, 1995
- A time to pregnancy questionnaire designed for long term recall: validity in Oxford, England.Journal of Epidemiology and Community Health, 1995