Abstract Background In small clinical studies, preterm birth was associated with altered cardiac structure and increased cardiovascular mortality in the young. Objectives The goal of this study was ...to determine the association between preterm birth and risk of incident heart failure (HF) in children and young adults. Methods This register-based cohort study included 2,665,542 individuals born in Sweden from 1987 to 2012 who were followed up from 1 year of age to December 31, 2013. The main study outcome was diagnosis of HF in the National Patient Register or the Cause of Death Register. The association between preterm birth and risk of incident HF was analyzed by using a Poisson regression model. Estimates were adjusted for maternal and pregnancy characteristics, socioeconomic status, and maternal and paternal cardiovascular disease. Results During 34.8 million person-years of follow-up (median 13.1 years), there were 501 cases of HF. After exclusion of 52,512 individuals with malformations (n = 196 cases), 305 cases of HF remained (0.88 per 100,000 person-years). Gestational age was inversely associated with the risk of HF. Compared with individuals born at term (≥37 weeks’ gestation), adjusted incidence relative risks for HF were 17.0 (95% confidence interval CI: 7.96 to 36.3) after extremely preterm birth (<28 weeks) and 3.58 (95% CI: 1.57 to 8.14) after very preterm birth (28 to 31 weeks). There was no risk increase after moderately preterm birth (32 to 36 weeks) (relative risk: 1.36; 95% CI: 0.87 to 2.13). Conclusions There was a strong association between preterm birth before 32 weeks of gestation and HF in childhood and young adulthood. Although the absolute risk of HF is low in young age, our findings indicate that preterm birth may be a previously unknown risk factor for HF.
Objective To provide risk estimates for celiac disease (CD) in Down syndrome (DS) compared with the general population. Study design In this nationwide Swedish case-control study, we examined the ...risk of CD in individuals with DS born between 1973 and 2008. Study participants consisted of 2 populations: 11 749 patients with biopsy-verified CD (villous atrophy VA, equivalent to Marsh grade III) who were identified through histopathology reports from the 28 pathology departments in Sweden and 53 887 population-based controls matched for sex, age, calendar year of birth, and county of residence. We used prospectively recorded data from Swedish health registers to identify individuals with DS. ORs were calculated using conditional logistic regression. Results Of the 11 749 individuals with CD, 165 had a diagnosis of DS (1.4%) compared with 55/53 887 controls (0.1%). This corresponded to an OR of 6.15 (95% CI = 5.09-7.43) for subsequent CD in individuals with DS compared with the general population. The association between DS and CD was not affected by maternal age at delivery, infant sex, or presence of type 1 diabetes mellitus in the child. Conclusions We found a sixfold increased risk of CD in individuals with DS. This study adds precision to the previously reported association between DS and CD.
Objective The objective of the investigation was to study the association between prior miscarriages and the risks of placental dysfunction disorders, including preeclampsia, stillbirth, birth of a ...small for gestational age (SGA) infant, placental abruption, and spontaneous preterm birth. Study Design In a population-based cohort study including 619,587 primiparous women, we estimated risks of placental dysfunction disorders for women with 1 (n = 68,185), 2 (n = 11,410) and 3 or more (n = 3823) self-reported prior miscarriages. Risks were calculated as odds ratios by unconditional logistic regression analysis and adjustments were made for maternal age, early pregnancy body mass index, height, smoking habits, country of birth, years of formal education, in vitro fertilization, chronic hypertension, pregestational diabetes, hypothyroidism, systemic lupus erythematosis, fetal sex, and year of childbirth. Results Compared with women with no prior miscarriage, women with 1 prior miscarriage had almost no increased risks. Women with 2 prior miscarriages had increased risks of spontaneous preterm birth, preterm (<37 weeks) SGA infant, and placental abruption. The rates of all disorders were higher for women with 3 or more prior miscarriages compared with women without prior miscarriages: preeclampsia, 5.83% vs 4.27%; stillbirth, 0.69% vs 0.33%, SGA infant, 5.09% vs 3.22%, placental abruption, 0.81% vs 0.41%; and spontaneous preterm birth, 6.45% vs 4.40%. The adjusted odds ratios for preterm (<37 weeks) disorders in women with 3 prior miscarriages were approximately 2. Conclusion History of 2 or more miscarriages is associated with an increased risk of placental dysfunction disorders and should be regarded as a risk factor in antenatal care.
Objective To estimate the risk for stress urinary incontinence and pelvic organ prolapse surgery related to vaginal birth or cesarean delivery. Study Design A cohort study of all women having their ...first and all subsequent deliveries by cesarean (n = 33,167), and an age-matched sample of women only having vaginal deliveries (n = 63,229) between 1973 and 1983. Hazard ratios were calculated using Cox regression models with 95% confidence intervals. Results Women only having vaginal deliveries had increased overall risks of incontinence (hazard ratio, 2.9; 95% confidence interval, 2.4–3.6) and prolapse surgery (hazard ratio, 9.2; 95% confidence interval, 7.0–12.1) compared with women only having cesarean deliveries. Conclusion Having only vaginal childbirths was associated with a significantly increased risk of stress urinary incontinence and pelvic organ prolapse surgery later in life compared with only having cesarean deliveries.
Background Prior studies relating parity with maternal cardiovascular disease (CVD) have been performed in relatively small study samples without accounting for pregnancy-related complications ...associated with CVD. Methods We examined the associations between parity and maternal risk of later-life CVD in a population-based cohort study using data from the Swedish population registers. Women born from 1932 to 1955 were followed until the occurrence of CVD, death, emigration, or end of follow-up (December 31, 2005). Cox proportional hazards models were used to estimate associations between parity and risk of CVD accounting for birth year, yearly income, education level, country of birth, hypertension (pregestational hypertension or gestational hypertension, with or without proteinuria), diabetes (type 1, type 2, or gestational diabetes), preterm birth, small for gestational age, and stillbirth. Results During a median follow-up time of 9.5 years (range 0-23.5), there were 65,204 CVD events in the full sample of women. Among 1,332,062 women, parity was associated with CVD in a J-shaped fashion, with 2 births representing the nadir of risk (global P value < .0001). Upon accounting for pregnancy-related complications in a subset of women with at least 1 childbirth after 1973 (n = 590,725), the association of parity with CVD was similar. Compared with women with 2 childbirths, the multivariable-adjusted hazard ratios (95% CIs) for women with 1 and ≥5 births were 1.09 (1.03-1.15) and 1.47 (1.37-1.57), respectively. Conclusions In conclusion, parity was associated with incident maternal CVD in a J-shaped fashion, even after accounting for socioeconomic factors and pregnancy-related complications.
Objective To determine the gestational age (GA)–specific risks for neonatal morbidity and use of interventions in infants born at 30 to 34 completed gestational weeks. Study design A population-based ...Swedish study including 6674 infants born during 2004–2008. Risks for neonatal morbidity and use of interventions were investigated with respect to GA and birth weight standard deviation scores. Results Acute lung disorder was diagnosed in 28%, hypoglycemia in 16%, bacterial infection in 15% and hyperbilirubinemia in 59% of the infants. Thirty-eight percent had received antenatal steroid therapy, 43% nasal continuous positive airway pressure, 5.5% required mechanical ventilation, 5.2% were treated with surfactant, and 30% with antibiotic therapy. Neonatal morbidity rates increased with decreasing GA, with odds ratios for different outcomes ranging from 2.1 to 23 at 30 weeks compared with 34 weeks of GA. Low birth weight standard deviation scores was more common at lower GA and was associated with increased morbidity rates. Conclusions Despite general advances in perinatal care, moderately preterm infants still have substantially increased risks for neonatal morbidity. Whereas the neonatal morbidity rate was similar to results of previous reports, management of respiratory problems differed markedly from other studies.
Objective The purpose of this study was to compare the risk of surgically treated stress urinary incontinence (SUI) and pelvic organ prolapse (POP) in relation to mode of delivery and age at first ...childbirth. Study Design This was a cohort study. Data from the Swedish Medical Birth Register on women with only cesarean delivery (n = 30,880 women) or only vaginal delivery (n = 59,585 women) were compared with the Swedish Patient Register to calculate incidence rates and hazard ratios (95% confidence interval CI) for SUI and POP surgery. Results In analyses that were stratified by age, vaginal delivery consistently increased the risks of SUI and POP surgery. Among vaginally delivered women who were ≥30 years old, incidence rates of POP surgery were 13.8 (95% CI, 12.7–15.1), and for younger women were 6.4 (95% CI, 6.0–6.8) per 10,000 person-years. Exclusion of instrumental vaginal delivery did not alter the conclusions. Conclusion Increasing age at first delivery increased the risk of subsequent SUI and POP surgery after both vaginal and cesarean delivery.
Objective The objective of the study was to determine the risk for pelvic organ prolapse surgery attributed to hysterectomy on benign indications Study Design In a nationwide longitudinal study, ...162,488 women with hysterectomy from 1973 through 2003 were matched to 470,519 population-based control women. Hazard ratios (HR) with 95% confidence interval (CI) were calculated using Cox regression analyses. Results In all, 3.2% (n = 5270) of women with hysterectomy had pelvic organ prolapse surgery, compared with 2.0% (n = 9437) in nonhysterectomized controls. Compared with nonhysterectomized controls, the overall HR for prolapse surgery was 1.7 (95% CI, 1.6 to 1.7) with the highest risks observed in women having had a vaginal hysterectomy (HR 3.8; 95% CI, 3.1 to 4.8). Compared with hysterectomized women with no vaginal births, the HR for prolapse surgery was 2.0 (95% CI, 0.9 to 4.1) among women with 1 vaginal childbirth and 11.3 (95 % CI, 6.0. to 21.1) among women with at least 4 vaginal births. Conclusion Hysterectomy is associated with an increased risk for subsequent pelvic organ prolapse surgery with multiparous women at particular risk.
Objective We hypothesized that preeclampsia partly shares pathophysiology with stillbirth, placental abruption, spontaneous preterm birth, and giving birth to a small-for-gestational-age infant, and ...that women who develop preeclampsia in the first pregnancy may have increased risks of the other outcomes in the second pregnancy, even in the absence of preeclampsia. Study Design In a nationwide Swedish cohort (n = 354,676) we estimated risks of adverse outcomes in the second pregnancy related to preterm (<37 weeks) and term (≥37 weeks) preeclampsia in the first pregnancy, using women without preeclampsia in the first pregnancy as reference. Results Women with prior preterm preeclampsia had, in second pregnancy, more than doubled risks of stillbirth, placental abruption, and preterm births, and an even greater risk of giving birth to a small-for-gestational-age infant. Conclusion Women with previous preterm preeclampsia have increased risks of adverse pregnancy outcomes in a second pregnancy despite the absence of preeclampsia.
Objective Knowledge about the causes of placental dysfunction disorders is limited. We performed an intergenerational study, focusing on the risks of placental dysfunction disorders in mothers and ...fathers who had been born small for gestational age (SGA). Study Design Using linked generational data from the Swedish Medical Birth Register from 1973-2006, we identified 321,383 mother-offspring units and 135,637 mother-father-offspring units. Results Compared with mothers who had not been born SGA, mothers who had been born SGA had the following adjusted odds ratios: late preeclampsia, 1.41 (95% confidence interval CI, 1.26–1.57); early preeclampsia, 1.87 (95% CI, 1.38–2.35); placental abruption, 1.60 (95% CI, 1.23–2.09); spontaneous preterm birth, 1.11 (95% CI, 1.00–1.23); and stillbirth, 1.24 (95% CI, 0.84–1.82). Compared with parents who had not been born SGA, the risk of preeclampsia was more than 3-fold increased if both parents had been born SGA, whereas if only the mother had been born SGA, the corresponding risk was increased by only 50%. Conclusion There is an intergenerational recurrence of placental dysfunction disorders on the maternal side and most likely also on the paternal side.