From the Guidelines
Maternal obesity is associated with a slightly increased risk of lower umbilical artery pH values during repeat cesarean deliveries, though this typically doesn't lead to adverse neonatal outcomes in most cases. When considering the impact of maternal obesity on repeat cesarean deliveries, several key factors come into play, including the potential for prolonged operative times and the increased risk of fetal acidemia 1. Key considerations for managing these risks include:
- Careful monitoring of fetal status during surgery
- Optimizing maternal positioning to minimize aortocaval compression
- Implementing prophylactic measures such as adequate pre-oxygenation and efficient surgical technique to minimize uterine incision-to-delivery time
- Appropriate maternal blood pressure management The physiological basis for these concerns relates to how maternal obesity can compromise uteroplacental blood flow through mechanical compression of major vessels, increased inflammatory markers, and potential technical challenges during surgery that may extend operative time 1. While most babies born to obese mothers via repeat cesarean have normal umbilical artery pH values, awareness of this potential risk allows for appropriate preparation and monitoring to ensure optimal outcomes. In the context of maternal obesity and repeat cesarean deliveries, the focus should be on minimizing risks and optimizing outcomes, with careful attention to the potential impacts of obesity on uteroplacental blood flow and fetal well-being 1.
From the Research
Maternal Obesity and Cesarean Delivery
- Maternal obesity is associated with an increased risk of cesarean delivery, as well as various surgical, anesthetic, and logistical challenges 2.
- The prevalence of obesity has reached pandemic proportions, and morbidly obese women are at increased risk of pregnancy complications and cesarean delivery 2, 3.
- Low transverse skin incisions and transverse uterine incisions are recommended for cesarean delivery in morbidly obese women, and closure of the subcutaneous layer is also recommended 2.
Maternal Obesity and Fetal Acidosis
- Maternal obesity is associated with increased odds of umbilical artery pH less than 7.1 and base deficit 12 mmol or greater at the time of scheduled cesarean delivery under neuraxial anesthesia 4.
- However, another study found that maternal BMI is not associated with lower umbilical arterial pH in women having scheduled cesarean delivery under spinal anesthesia, and that the severity of spinal anesthesia induced hypotension is a significant predictor of low umbilical arterial pH 5.
- The relationship between maternal obesity and fetal umbilical arterial pH is complex and may be influenced by various factors, including the type of anesthesia used and the presence of maternal medical comorbidities 4, 5.
Intraoperative Complications and Maternal Obesity
- Maternal obesity is not associated with an increased risk of intraoperative complications during cesarean delivery, and may even be associated with a lower risk of complications in some cases 6.
- The risk of intraoperative complication does not appear to be increased in obese women, even among those with super obesity, although the risk of postoperative complications may be increased 6.
- The types of incisions and techniques used during cesarean delivery, as well as the use of thromboprophylaxis and prophylactic antibiotics, may help to reduce the risk of intraoperative and postoperative complications in morbidly obese women 2, 6.