The ICE-MCH Study: Examining the Combined Impact of Pre-pregnancy BMI and Gestational Weight Gain on the Risk of Pre-labour and Intrapartum Caesarean Section

Obesity has long been associated with a higher risk of complications during pregnancy and delivery, including the need for cesarean section. However, the role of gestational weight gain in this relationship has been less clear. 

The present study examined the integrated effect of pre-pregnancy weight and gestational weight gain on pre-labor and intrapartum caesarean section risk. Based on Icelandic registries, the study collected data on 22,763 single, term, and live deliveries in 2003–2014 from the Icelandic Maternal and Child Health Study (ICE-MCH). 

It categorized Pre-pregnancy body mass index into underweight, normal weight, overweight and obese. 

The study observed-

• Higher risk of pre-labor and intrapartum cesarean section in obese women than in normal-weight women in all categories of gestational weight gain. 
• Gestational weight gain above the recommended range increased the risk of intrapartum cesarean section among normal-weight and overweight women. 
• Gestational weight gain below the recommended range increased the risk of pre-labor caesarean section only among overweight women. 
• Women, obese before pregnancy posed a greater risk of caesarean section irrespective of gestational weight gain. 
• Women with normal weight or overweight before pregnancy and gained weight above the recommended range during pregnancy may also have an increased risk of cesarean section.

These findings suggest that the relationship between gestational weight gain and cesarean-section risk is complex and may vary depending on pre-pregnancy weight.

The implications of these findings are important for both healthcare providers and expectant mothers. Healthcare providers should consider the pre-pregnancy weight of their patients when assessing the risk of cesarean section and should also monitor gestational weight gain closely to ensure it falls within the recommended range. Expectant mothers should strive to maintain a healthy weight before and during pregnancy and consult with their healthcare provider if they have concerns about their weight gain.

This study provides valuable insights into the complex relationship between pre-pregnancy weight, gestational weight gain, and cesarean section risk. By considering both factors, healthcare providers can provide better care to their patients and help ensure safer deliveries for both mother and baby.

Eloranta AM, Gunnarsdottir I, Thorisdottir B, Gunnlaugsson G, Birgisdottir BE, Thorsdottir I, et al. The combined effect of pre-pregnancy body mass index and gestational weight gain on the risk of pre-labour and intrapartum caesarean section—The ICE-MCH study. PLoS ONE. 2023;18(1): e0280060. https://doi.org/10.1371/journal.pone.0280060