M Joffe1, Z Li. 1. Academic Department of Public Health, St. Mary's Hospital Medical School, London, United Kingdom.
Abstract
OBJECTIVE: To examine the relationship of subfertility with miscarriage, low birth weight, and preterm delivery. DESIGN: Comparison of time to pregnancy distributions between pregnancies that had different outcomes. Three comparisons were made: (a) miscarriages with live births; within live births, (b) low birth weight infant (up to 2,500 grams) or not low birth weight; (c) preterm birth (37 weeks or less) or not preterm. Cox regression was used to adjust for covariates. POPULATION: All first pregnancies were analyzed from the National Child Development Study, a large survey of young adults aged 33 years, which is nationally representative of the British-born population. MAIN OUTCOME MEASURES: The distribution of the time taken to conceive (time to pregnancy), miscarriage, birth weight, and preterm delivery. RESULTS: Pregnancies that ended in miscarriage tended to take 23% longer to conceive, after adjustment for the other variables. Pregnancies that resulted in preterm delivery tended to take 15% longer to conceive. There was no statistically significant association with low birth weight. CONCLUSIONS: Delay in time to conception is a risk factor for poor obstetric outcome, irrespective of medical intervention.
OBJECTIVE: To examine the relationship of subfertility with miscarriage, low birth weight, and preterm delivery. DESIGN: Comparison of time to pregnancy distributions between pregnancies that had different outcomes. Three comparisons were made: (a) miscarriages with live births; within live births, (b) low birth weight infant (up to 2,500 grams) or not low birth weight; (c) preterm birth (37 weeks or less) or not preterm. Cox regression was used to adjust for covariates. POPULATION: All first pregnancies were analyzed from the National Child Development Study, a large survey of young adults aged 33 years, which is nationally representative of the British-born population. MAIN OUTCOME MEASURES: The distribution of the time taken to conceive (time to pregnancy), miscarriage, birth weight, and preterm delivery. RESULTS: Pregnancies that ended in miscarriage tended to take 23% longer to conceive, after adjustment for the other variables. Pregnancies that resulted in preterm delivery tended to take 15% longer to conceive. There was no statistically significant association with low birth weight. CONCLUSIONS: Delay in time to conception is a risk factor for poor obstetric outcome, irrespective of medical intervention.
Entities:
Keywords:
Age Factors; Behavior; Biology; Birth Weight; Body Weight; Demographic Factors; Developed Countries; Economic Factors; Educational Status; Europe; Fertility; Fertility Measurements; Fetal Death; First Pregnancy Intervals; Low Birth Weight; Maternal Age; Mortality; Northern Europe; Parental Age; Physiology; Population; Population Characteristics; Population Dynamics; Pregnancy; Pregnancy Intervals; Pregnancy Outcomes--determinants; Reproduction; Risk Factors; Smoking; Socioeconomic Factors; Socioeconomic Status; Time Factors; United Kingdom
Authors: M Joffe; L Bisanti; P Apostoli; P Kiss; A Dale; N Roeleveld; M-L Lindbohm; M Sallmén; M Vanhoorne; J P Bonde Journal: Occup Environ Med Date: 2003-10 Impact factor: 4.402
Authors: Susan E Puumala; Julie A Ross; James H Feusner; Gail E Tomlinson; Marcio H Malogolowkin; Mark D Krailo; Logan G Spector Journal: Hum Reprod Date: 2012-04-03 Impact factor: 6.918