BACKGROUND AND PURPOSE: 

• Lamont et al. (Obstetrics & Gynecology, 2022) investigated subsequent risk for stillbirth among women with and without previous stillbirth    

METHODS: 

• Cohort study 
• Population 
  • Women from Malta, Finland or Scotland who had at least two singleton deliveries 
• Exposures 
  • Stillbirth in first pregnancy 
  • Live birth in first pregnancy 
• Study design 
  • Primary outcome was assessed using a Cox proportional hazards model 
  • Time-to-event analyses were conducted to investigate whether first pregnancy outcome had an effect on time to or the number of pregnancies preceding subsequent stillbirth 
• Primary outcome 
  • Risk of stillbirth in any subsequent pregnancy 

RESULTS: 

• 1,064,564 women 
  • Stillbirth at first pregnancy: 6288 women (0.59%) 
• Compared to live birth, women with a stillbirth in the first pregnancy were more likely to have a subsequent stillbirth 
  • Adjusted hazard ratio 2.25, (95% CI, 1.86 to 2.7) 
• Women who had a stillbirth in the first pregnancy  
  • Were less likely to have had their first antenatal appointment at ≤12 weeks  
  • Had increased risk for stillbirth with increasing parity in subsequent pregnancies  
  • Were more likely to have another pregnancy within 1 year 
• The following were independently associated with subsequent stillbirth 
  • Maternal age younger <25 years or ≥40 years  
  • Smoking 
  • Low socioeconomic status 
  • Not having a partner 
  • Pre-existing diabetes 
  • Preeclampsia 
  • Placental abruption 
  • Fetal growth restriction  
• Absolute risk of subsequent stillbirth 
  • Previous live birth: 0.5% 
  • Previous stillbirth: 2.5% 

CONCLUSION: 

• Prior stillbirth increases the risk of subsequence stillbirth, regardless of number of pregnancies 
• The authors state 

…women with a stillbirth in their first pregnancy have more than double the risk of stillbirth in any subsequent pregnancy 

Despite significantly raised relative risk, the absolute risk remains low 

Learn More – Primary Sources: 

Risk of Recurrent Stillbirth in Subsequent Pregnancies 

Related ObG Topics: