title: The Effect of Interpregnancy Interval on the Recurrence Rate of Spontaneous Preterm Birth: A Retrospective Cohort Study.
abstract: ObjectiveWe assessed, in women with a previous spontaneous preterm birth, the effect of interpregnancy interval on the subsequent preterm birth rate.DesignRetrospective cohort study.SettingA nationwide longitudinal dataset of the the Netherlands Perinatal Registry.PopulationWomen with three sequential singleton pregnancies between 1999 and 2009 and a spontaneous preterm birth <37 weeks in the first pregnancy.MethodsWe evaluated the impact of interpregnancy interval on the course of the next pregnancies. Antenatal death and/or congenital abnormalities were excluded. Conventional and conditional logistic regression analysis were applied. We adjusted for maternal age, ethnicity, socioeconomic status, artificial reproductive techniques, and year of birth.Main Outcome MeasuresOutcomes studied were preterm birth <37 weeks, <32 weeks, low birth weight <2500 g, and small for gestational age <10th percentile.ResultsAmong 2,361 women with preterm birth in the first pregnancy, logistic regression analysis indicated a significant effect of a short interpregnancy interval (0-5 mo) on recurrent preterm birth <37 weeks (odds ratio [OR], 2.22; 95% confidence interval [CI], 1.62-3.05), <32 weeks (OR, 2.90; 95% CI, 1.43-5.87), and low birth weight (OR, 2.69; 95% CI, 1.79-4.03). In addition, a long interval (≥60 mo) had a significant effect on preterm birth <37 weeks (OR, 2.19; 95% CI, 1.29-3.74). Conditional logistic regression analysis confirmed the effect of a short interval on the recurrence of preterm birth rate <37 weeks and low birth weight.ConclusionIn women with a previous spontaneous preterm birth, a short interpregnancy interval has a strong impact on the risk of preterm birth before 37 weeks and low birth weight in the next pregnancy, irrespective of the type of analysis performed.
authors.affiliation: Department of Obstetrics and Gynecology, Academic Medical Centre, Amsterdam, The Netherlands.
authors.forename: Bouchra
authors.initials: B
authors.lastname: Koullali
authors.affiliation: Department of Obstetrics and Gynecology, Academic Medical Centre, Amsterdam, The Netherlands.
authors.forename: Esme I
authors.initials: EI
authors.lastname: Kamphuis
authors.affiliation: Department of Clinical Epidemiology, Biostatistics, and Bioinformatics, Academic Medical Centre, Amsterdam, The Netherlands.
authors.forename: Michel H P
authors.initials: MH
authors.lastname: Hof
authors.affiliation: The Robinson Research Institute, School of Medicine, University of Adelaide, The South Australian Health and Medical Research Institute Adelaide, Australia.
authors.forename: Sarah A
authors.initials: SA
authors.lastname: Robertson
authors.affiliation: Department of Obstetrics and Gynecology, Academic Medical Centre, Amsterdam, The Netherlands.
authors.forename: Eva
authors.initials: E
authors.lastname: Pajkrt
authors.affiliation: Department of Obstetrics and Gynecology, VU University Medical Centre, Amsterdam, The Netherlands.
authors.forename: Christianne J M
authors.initials: CJ
authors.lastname: de Groot
authors.affiliation: The Robinson Research Institute, School of Medicine, University of Adelaide, The South Australian Health and Medical Research Institute Adelaide, Australia.
authors.forename: Ben W J
authors.initials: BW
authors.lastname: Mol
authors.affiliation: Department of Obstetrics and Gynecology, Academic Medical Centre, Amsterdam, The Netherlands.
authors.forename: Anita C J
authors.initials: AC
authors.lastname: Ravelli
mesh_terms: D000328:Adult; D001721:Birth Intervals; D005260:Female; D005865:Gestational Age; D006801:Humans; D007230:Infant, Low Birth Weight; D007236:Infant, Small for Gestational Age; D016015:Logistic Models; D008137:Longitudinal Studies; D009426:Netherlands / Q000453:epidemiology; D011247:Pregnancy; D047928:Premature Birth / Q000453:epidemiology*; D012008:Recurrence; D012042:Registries; D012044:Regression Analysis; D012189:Retrospective Studies; D055815:Young Adult