Women with major adverse pregnancy outcomes face an increased risk of long-term mortality, according to a recent study published in JAMA Internal Medicine.
Takeaways
- Women who experience adverse pregnancy outcomes, including preterm delivery, small for gestational age infants, preeclampsia, hypertensive disorders, and gestational diabetes, face a notable increase in long-term mortality risk.
- Mortality risks associated with adverse pregnancy outcomes extend beyond cardiovascular disease, encompassing cancer, respiratory disorders, and diabetes, highlighting the multifaceted impact on women's health.
- The increased mortality risk persists for over 40 years following a major adverse pregnancy outcome, emphasizing the need for long-term monitoring and support for affected women.
- Different adverse pregnancy outcomes are associated with distinct risk profiles, influenced by factors such as maternal age, education level, income, body mass index, and smoking status, necessitating tailored preventative strategies.
- The study underscores the importance of proactive measures and long-term follow-up to mitigate mortality risks associated with adverse pregnancy outcomes, advocating for comprehensive support systems in women's healthcare.
An association has been found between adverse pregnancy outcomes and future cardiometabolic disorder risks, but there is little data about long-term mortality risks following adverse pregnancy outcomes. Approximately 30% of women experience an adverse pregnancy outcome, indicating a need to improve understanding of risks.
Current data has focused on determining an association between a single adverse pregnancy outcome and future mortality risk. Therefore, a study evaluating multiple pregnancy outcomes across a woman’s life can help clarify the effects of specific adverse pregnancy outcomes on mortality.
To evaluate long-term mortality risks associated with 5 major adverse pregnancy outcomes, investigators conducted a national cohort study. Participants were selected from the Swedish Medical Birth Register and included women with a singleton delivery between 1973 and 2015 without missing pregnancy duration or infant birth weight data.
The 5 major adverse pregnancy outcomes included preterm delivery, small for gestational age, preeclampsia, other hypertensive disorders, and gestational diabetes. Data about these outcomes was available from the Medical Birth Register.
Follow-up lasted from first delivery through December 31, 2018, with a maximum follow-up duration of 46 years and a median duration of 25 years. The Swedish Death Register was assessed to determine deaths during this period.
Covariates included calendar year of delivery, parity, education level, employment status, income, body mass index (BMI), smoking status, country of maternal birth, and prepregnancy hypertension or diabetes. Adjustments were also made for maternal age in all analyses.
Experiencing 1 or more adverse outcome was reported by 30% of included women, and 2 or more by 8%. Small for gestational age infant was the most common outcome reported in 10% of deliveries, followed by preterm delivery in 5% of deliveries. These outcomes were also the most common pair, reported together in 1.4% of women.
Women with these outcomes were often younger at first delivery, had a reduced education level or income, and smoked. Those with preeclampsia often had a reduced education level or income, higher BMI, and smoked.
Those with hypertensive disorders or gestational diabetes were often older at first delivery, had a higher income or BMI, and did not smoke. Death was reported in 4% of women, with a median age at death of 59 years.
An independent association with increased mortality risk was reported for all 5 adverse pregnancy outcomes. The hazard ratios (HRs) for gestational diabetes, preterm delivery, small for gestational age, other hypertensive disorders, and preeclampsia with death were 1.52, 1.41, 1.30, 1.27, and 1.13, respectively.
While HRs remained stable for most outcomes, the HR for preterm delivery was highest for the first 10 years, after which it would decline. However, all HRs remained significantly elevated at 30 to 46 years following delivery.
Of deaths, 14% were linked to cardiovascular disease, 49% to cancer, 4% to respiratory disorders, 1% to diabetes, and 32% to other causes. The risk of mortality from cardiovascular disease was increased 1.5- to 2.5-fold among women with any major adverse pregnancy outcome vs those without the respective adverse pregnancy outcome.
An over 2-fold increased risk of respiratory mortality and 1.1 to 1.2-fold increased risk of cancer mortality was also seen among women with preterm or small for gestational age delivery. Those with gestational diabetes had a 25-fold increased risk of diabetes mortality, vs over 2-fold in those with preterm delivery or preeclampsia.
These results indicated increased mortality risk for over 40 years among women experiencing a major adverse pregnancy outcome. Investigators recommended preventative action and long-term follow-up be utilized to support women with adverse pregnancy outcomes.
Reference
Crump C, Sundquist J, Sundquist K. Adverse pregnancy outcomes and long-term mortality in women. JAMA Intern Med. 2024. doi:10.1001/jamainternmed.2024.0276
