Is stillbirth associated with long-term atherosclerotic morbidity?

Fetal loss and long-term maternal morbidity and mortality: A systematic review and meta-analysis

BACKGROUND

Evidence suggests common pathways between pregnancy losses and subsequent long-term maternal morbidity, rendering pregnancy complications an early chronic disease marker. There is a plethora of studies exploring associations between miscarriage and stillbirth with long-term adverse maternal health; however, these data are inconclusive.

METHODS AND FINDINGS

We systematically searched MEDLINE, EMBASE, AMED, BNI, CINAHL, and the Cochrane Library with relevant keywords and MeSH terms from inception to June 2023 (no language restrictions). We included studies exploring associations between stillbirth or miscarriage and incidence of cardiovascular, malignancy, mental health, other morbidities, and all-cause mortality in women without previous pregnancy loss. Studies reporting short-term morbidity (within a year of loss), case reports, letters, and animal studies were excluded. Study selection and data extraction were performed by 2 independent reviewers. Risk of bias was assessed using the Newcastle Ottawa Scale (NOS) and publication bias with funnel plots. Subgroup analysis explored the effect of recurrent losses on adverse outcomes. Statistical analysis was performed using an inverse variance random effects model and results are reported as risk ratios (RRs) with 95% confidence intervals (CIs) and prediction intervals (PIs) by combining the most adjusted RR, odds ratios (ORs) and hazard ratios (HRs) under the rare outcome assumption. We included 56 observational studies, including 45 in meta-analysis. There were 1,119,815 women who experienced pregnancy loss of whom 951,258 had a miscarriage and 168,557 stillbirth, compared with 11,965,574 women without previous loss. Women with a history of stillbirth had a greater risk of ischaemic heart disease (IHD) RR 1.56, 95% CI [1.30, 1.88]; p < 0.001, 95% PI [0.49 to 5.15]), cerebrovascular (RR 1.71, 95% CI [1.44, 2.03], p < 0.001, 95% PI [1.92, 2.42]), and any circulatory/cardiovascular disease (RR 1.86, 95% CI [1.01, 3.45], p = 0.05, 95% PI [0.74, 4.10]) compared with women without pregnancy loss. There was no evidence of increased risk of cardiovascular disease (IHD: RR 1.11, 95% CI [0.98, 1.27], 95% PI [0.46, 2.76] or cerebrovascular: RR 1.01, 95% CI [0.85, 1.21]) in women experiencing a miscarriage. Only women with a previous stillbirth were more likely to develop type 2 diabetes mellitus (T2DM) (RR: 1.16, 95% CI [1.07 to 2.26]; p < 0.001, 95% PI [1.05, 1.35]). Women with a stillbirth history had an increased risk of developing renal morbidities (RR 1.97, 95% CI [1.51, 2.57], p < 0.001, 95% [1.06, 4.72]) compared with controls. Women with a history of stillbirth had lower risk of breast cancer (RR: 0.80, 95% CI [0.67, 0.96], p-0.02, 95% PI [0.72, 0.93]). There was no evidence of altered risk of other malignancies in women experiencing pregnancy loss compared to controls. There was no evidence of long-term mental illness risk in women with previous pregnancy losses (stillbirth: RR 1.90, 95% CI [0.93, 3.88], 95% PI [0.34, 9.51], miscarriage: RR 1.78, 95% CI [0.88, 3.63], 95% PI [1.13, 4.16]). The main limitations include the potential for confounding due to use of aggregated data with variable degrees of adjustment.

CONCLUSIONS

Our results suggest that women with a history of stillbirth have a greater risk of future cardiovascular disease, T2DM, and renal morbidities. Women experiencing miscarriages, single or multiple, do not seem to have an altered risk.

The risk of cardiovascular diseases after miscarriage, stillbirth, and induced abortion: a systematic review and meta-analysis

Aims

Miscarriage and stillbirth have been included in cardiovascular disease (CVD) risk guidelines, however heterogeneity in exposures and outcomes and the absence of reviews assessing induced abortion, prevented comprehensive assessment. We aimed to perform a systematic review and meta-analysis of the risk of cardiovascular diseases for women with prior pregnancy loss (miscarriage, stillbirth, and induced abortion).

Methods and results

Observational studies reporting risk of CVD, coronary heart disease (CHD), and stroke in women with pregnancy loss were selected after searching MEDLINE, Scopus, CINAHL, Web of Knowledge, and Cochrane Library (to January 2020). Data were extracted, and study quality were assessed using the Newcastle-Ottawa Scale. Pooled relative risk (RR) and 95% confidence intervals (CIs) were calculated using inverse variance weighted random-effects meta-analysis.Twenty-two studies involving 4 337 683 women were identified. Seven studies were good quality, seven were fair and eight were poor. Recurrent miscarriage was associated with a higher CHD risk (RR = 1.37, 95% CI: 1.12-1.66). One or more stillbirths was associated with a higher CVD (RR = 1.41, 95% CI: 1.09-1.82), CHD (RR = 1.51, 95% CI: 1.04-1.29), and stroke risk (RR = 1.33, 95% CI: 1.03-1.71). Recurrent stillbirth was associated with a higher CHD risk (RR = 1.28, 95% CI: 1.18-1.39). One or more abortions was associated with a higher CVD (RR = 1.04, 95% CI: 1.02-1.07), as was recurrent abortion (RR = 1.09, 95% CI: 1.05-1.13).

Conclusion

Women with previous pregnancy loss are at a higher CVD, CHD, and stroke risk. Early identification and risk factor management is recommended. Further research is needed to understand CVD risk after abortion.

Identifying risk factors for perinatal mortality from a preceding pregnancy without perinatal mortality

OBJECTIVE

To identify risk factors in first pregnancy for perinatal mortality in the subsequent pregnancy.

METHODS

A retrospective population-based nested case-control study was conducted, including all women with two first singleton consecutive deliveries. Women with perinatal mortality in their first pregnancy were excluded, and cases with perinatal mortality in the second pregnancy were compared with controls who delivered a live birth. Characteristics and complications of the first pregnancy were compared between the groups using multivariable logistic models.

RESULTS

A total of 43 043 women were included in the study, 385 (0.9%) were cases. Cases, as compared with controls (live births), were younger (22.62 ± 4.0 vs 23.22 ± 4.0 years), with shorter inter-pregnancy interval (1.38 ± 1.55 vs 1.56 ± 1.53 years), and were more likely to have the following complications in their first pregnancy: severe pre-eclampsia (3.4% vs 1.7%), small for gestational age (12.5% vs 8.0%), preterm delivery (17.7% vs 7.8%), and congenital or chromosomal malformations (9.6% vs 5.9%). In multivariable analysis the risk for perinatal mortality was greater with each additional complication (adjused odds ratio [aOR] 1.64, 95% confidence interval [CI] 1.30-2.07, P < 0.001; aOR 2.55, 95% CI 1.61-4.04, P < 0.001; aOR 7.88, 95% CI 3.81-16.29, P < 0.001 for one, two, and three or more complications, compared with no complications, respectively).

CONCLUSION

Complications in first pregnancy ending with live birth are associated with increased risk for perinatal mortality in a subsequent pregnancy.

Uterine rupture and long-term cardiovascular hospitalization of the offspring

BACKGROUND

Uterine rupture is associated with severely adverse maternal and neonatal outcomes. The association between uterine rupture and long-term cardiovascular hospitalization of the offspring has not been investigated yet.

METHODS

In a population-based cohort study, the incidence of cardiovascular related hospitalizations was compared between singletons born to mothers with and without uterine rupture in the current pregnancy. Cardiovascular hospitalization up to the age of 18 years was assessed according to a predefined set of ICD-9 codes associated with offspring hospitalization. Multiple gestations, perinatal deaths, lacking prenatal care, and children with congenital malformations or chromosomal abnormalities were excluded from the study. A Kaplan-Meier survival curve was used to assess cumulative incidence of cardiovascular hospitalization of the offspring. A Cox proportional hazards model was performed to control for confounders.

RESULTS

During the study period, 238,622 newborns met the inclusion criteria, of which 0.053% (n = 127) were born to mothers with uterine rupture in the current pregnancy. Children born to mothers with uterine rupture had significantly higher rates of cardiovascular related hospitalization (Kaplan-Meier's survival curve log-rank test, p=.005).

CONCLUSION

Being born following uterine rupture is an independent risk factor for long-term pediatric cardiovascular hospitalization. Highlights Uterine rupture is a risk factor for long-term pediatric cardiovascular related hospitalization. Rising rate of CS potentially associate to long-term offspring cardiovascular disease. Cardiovascular surveillance is needed for newborns delivered after uterine rupture.

Adverse pregnancy outcomes and subsequent development of connective tissue disease in the UK: an epidemiological study

OBJECTIVE

This study assessed prevalence of connective tissue disease (CTDs), systemic lupus erythematosus (SLE), antiphospholipid syndrome (APS) and antiphospholipid antibodies (aPL) in women with previous adverse pregnancy outcome compared with uncomplicated livebirths.

DESIGN

Retrospective case-control study.

SETTING

UK Primary Care.

POPULATION OR SAMPLE

Records of women, 18 years and older, within the Clinical Practice Research Datalink (CPRD) (1 January 2000-31 December 2013).

METHODS

Clinical Practice Research Datalink was searched for pregnancy terms to identify adverse pregnancy outcome. Each identified case was matched to five livebirths.

MAIN OUTCOME MEASURES

Diagnosis of SLE, CTD, APS or autoimmune antibodies. Poisson regression was performed to calculate relative risk ratios (RR), comparing adverse pregnancy outcome with livebirth cohorts.

RESULTS

Clinical Practice Research Datalink identified 20 123 adverse pregnancy outcomes matched to 97 323 livebirths, with a total of 875 590 person-years follow up. Median follow up from study entry was 7.29 years (SD 4.39). Compared with women with an uncomplicated livebirth, women with adverse pregnancy outcome had an increased risk of developing CTD or autoimmune antibodies (RR 3.20, 95% CI 2.90-3.51). Risk was greatest following a stillbirth (RR 5.82, 95% CI 4.97-6.81). For CTD and SLE, the risk was greatest within the first 5 years of adverse pregnancy outcome. Risk for aPL and APS diagnosis was highest ≥5 years from adverse pregnancy outcome.

CONCLUSIONS

Adverse pregnancy outcome is associated with increased risk of developing maternal CTD, including SLE. Either immunological factors predispose women to adverse pregnancy outcome and subsequent CTD diagnosis or, alternatively, adverse pregnancy outcome initiates autoimmune events which culminate in CTD in later life.

TWEETABLE ABSTRACT

Stillbirth is associated with increased maternal risk of developing systemic lupus erythematosus (SLE).

Early or late pregnancy loss and development of clinical cardiovascular disease risk factors: a prospective cohort study

OBJECTIVE

To assess the association between the outcome of a woman's first pregnancy and risk of clinical cardiovascular disease risk factors.

DESIGN

Prospective cohort study.

SETTING AND POPULATION

Nurses' Health Study II.

METHODS

Multivariable-adjusted Cox proportional hazards models were used to compute hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations between first pregnancy outcome and hypertension, type 2 diabetes, and hypercholesterolemia.

MAIN OUTCOME MEASURES

Hypertension, type 2 diabetes, and hypercholesterolemia.

RESULTS

Compared to women who reported a singleton live first birth, women with early spontaneous abortion (<12 weeks) had a greater rate of type 2 diabetes (HR: 1.20; 95% CI: 1.07-1.34) and hypercholesterolemia (HR: 1.06; 95% CI: 1.02-1.10), and a marginally increased rate of hypertension (HR: 1.05, 95% CI: 1.00-1.11). Late spontaneous abortion (12-19 weeks) was associated with an increased rate of type 2 diabetes (HR: 1.38; 95% CI: 1.14-1.65), hypercholesterolemia (HR: 1.11; 95% CI: 1.03-1.19), and hypertension (HR: 1.15; 95% CI: 1.05-1.25). The rates of type 2 diabetes (HR: 1.45; 95% CI: 1.13-1.87) and hypertension (HR: 1.15; 95% CI: 1.01-1.30) were higher in women who delivered stillbirth. In contrast, women whose first pregnancy ended in an induced abortion had lower rates of hypertension (HR: 0.87; 95% CI: 0.84-0.91) and type 2 diabetes (HR: 0.89; 95% CI: 0.79-0.99) than women with a singleton live birth.

CONCLUSIONS

Several types of pregnancy loss were associated with an increased rate of hypertension, type 2 diabetes, and hypercholesterolemia, which may provide novel insight into the pathways through which pregnancy outcomes and CVD are linked.

TWEETABLE ABSTRACT

Pregnancy loss is associated with later maternal risk of hypertension, type 2 diabetes, and hypercholesterolemia.

Long-Term Effects of Pregnancy Complications on Maternal Health: A Review

Background: Most pregnancy-related medical complications appear to resolve at delivery or shortly thereafter. Common examples are preterm labor, placental abruption, preeclampsia, and gestational diabetes. Women who developed such complications are known to be at increased risk of developing similar complications in future pregnancies. It has recently become evident that these women are at an increased risk of long term medical complications. Methods: A search through scientific publications in English regarding the association of obstetric complications and long-term maternal illness. Results: There is a clear association between various obstetric complications and long-term effects on maternal health. Conclusions: Women with a history of adverse pregnancy outcomes are at increased risk of cardiovascular and metabolic diseases later in life. Data increasingly links maternal vascular, metabolic, and inflammatory complications of pregnancy with an increased risk of vascular disease in later life.

Maternal characteristics of pregnancies with intrauterine fetal demise

OBJECTIVE

To identify maternal characteristics independently associated with pregnancies resulting in intrauterine fetal demise (IUFD).

STUDY DESIGN

This was a population-based cohort study of all births taking place at the McGill University Health Centre in Montreal, Canada, between 2001 and 2007, using the McGill University Obstetrics and Neonatal Database. Maternal characteristics were compared between pregnancies that resulted in IUFD and control pregnancies resulting in live newborns. A logistic regression analysis was constructed to identify parameters independently associated with IUFD.

RESULTS

We identified 20,744 births during the study period, 87 of which were complicated by IUFD. Mothers with IUFD were more likely to be younger, with less formal education, higher rates of smoking during pregnancy, and more fetal anomalies (42.5% vs. 7.5%, P<0.001). After exclusion of pregnancies with congenital and/or chromosomal abnormalities, less formal education (7 vs. 13.6 school years, P<0.001) and smoking during pregnancy (24% vs. 7.7%, P<0.001) remained significantly more common in pregnancies resulting in IUFD. In the multivariable regression analysis both smoking and number of maternal school years were independently associated with IUFD pregnancies (OR 2.22 for smoking, P=0.007 and OR 0.865 for number of school years, P<0.001).

CONCLUSION

Lower levels of education and smoking during pregnancy are independent predictors of IUFD.

Maternal-placental syndrome and future risk of accelerated cardiovascular events in Parous Swedish women with systemic lupus erythematosus - a population-based retrospective cohort study with time-to-event analysis

OBJECTIVES

Women with SLE are at increased risk of cardiovascular events (CVEs), but a relationship with traditional cardiovascular and SLE-specific risk factors has not been established. In unselected populations, adverse pregnancy outcomes linked to maternal-placental syndrome (MPS) are associated with an increased risk of CVEs. However, the effect of MPS on CVEs is unknown in women with SLE. The aim of this study was to determine if MPS increased the risk and accelerated the development of CVEs in women with SLE.

METHODS

Utilizing Swedish population registries, parous women with SLE were identified. Exposures were the following: MPS defined as hypertensive disorders of pregnancy; small-for-gestational-age; placental abruption and stillbirth; and preterm delivery <34 weeks. Outcomes were CVE encompassing cardiovascular morbidity and mortality. Risk of an event was modelled using Cox proportional hazards adjusted for year of delivery, age at CVE, severity of SLE and cardiovascular risk factors. Time-to-CVE was estimated using Kaplan-Meier methods.

RESULTS

Over the 38-year study period, there were 3977 women with 7410 pregnancies, of whom 413 (10.2%) suffered a CVE. Hazard of CVE was higher in those with MPS, particularly when MPS (adjusted HR = 1.64; 95% CI: 1.31, 2.05) was combined with preterm delivery < 34 weeks' gestation (adjusted HR 1.99; 95% CI 1.39, 2.84). There was accelerated development of CVEs in women with MPS of 10.5% (vs 7.3% in uncomplicated pregnancies) over the 38-year interval (P < 0.05).

CONCLUSION

Pregnancy complicated by MPS and preterm delivery exerts an independent effect to increase the risk and accelerate the development of CVEs in parous women with SLE.