(25) Diabetes and Cardiovascular Diseases in Women with Pregnancies Complicated by Vaginal Bleeding: Danish Population-Based Cohort Study

Publication Number: 356

Background: Vaginal bleeding (VB) affects up to 30% of recognized pregnancies. The risk of cardiovascular outcomes following childbirth complicated by VB not ending in a miscarriage is not well investigated.

Objectives: To examine an association between childbirth affected by VB and subsequent women’s risks of diabetes and cardiovascular diseases.

Methods: This was a registry-based cohort study in Denmark. Between 1979 and 2017, among 1,329,331 women we identified 3,085,955 pregnancies. Of these, 69,230 ended in childbirth affected by VB within 20 gestational weeks; 2,180,855 ended in VB-unaffected childbirth; 578,355 ended in termination, and 258,430 ended in a miscarriage. The outcomes were diabetes types 1 and 2, hypertension, ischaemic heart disease, including myocardial infarction, atrial fibrillation or flutter, heart failure, ischaemic and haemorrhagic stroke, coronary artery bypass grafting, and percutaneous coronary intervention. We computed the incidence rates per 10,000 person-years and cumulative incidence of the outcomes at 40 years of follow-up, hazard ratios (HRs) with 95% confidence intervals controlled for age, calendar year, comorbidities, and socioeconomics at baseline using Cox proportional hazards regression adjusted conventionally and using inverse probability of treatment weights.

Results: At the end of follow-up, among women with VB-affected vs VB-unaffected childbirths, the cumulative risks of the outcomes were 4.5% vs 3.5% for diabetes type 1; 13.8% vs 11.1% for diabetes type 2; 25.1% vs 21.4% for hypertension; 10.6% vs 8.2% for ischaemic heart disease, including 2.9% vs 2.6% for myocardial infarction; 5.3% vs 4.4% for atrial fibrillation or flutter; 2.3% vs 2.0% for heart failure; 5.1% vs 4.0% for ischaemic stroke; 1.8% vs 1.4% for haemorrhagic stroke; 0.5% vs 0.4% for coronary artery bypass graft; and 2.4% vs 1.9% for percutaneous coronary intervention. Adjusted HRs were 1.2 to 1.3-fold increased for diabetes, hypertension, ischaemic heart disease, atrial fibrillation or flutter, heart failure, ischaemic and haemorrhagic stroke as well as a coronary artery bypass grafting. For comparisons of VB-affected childbirths with terminations, hazards were up to 1.3-fold increased for diabetes and 1.1-fold increased for hypertension, ischaemic heart disease, atrial fibrillation or flutter, and haemorrhagic stroke. HRs were unity when we compared having VB-affected childbirth with having a miscarriage.

Conclusions: Women’s hazards of diabetes and cardiovascular outcomes were increased following childbirths affected by VB when compared with VB-unaffected childbirths or terminations.