In a recent perspective published in PLOS Medicine, researchers have shed light on a concerning link between cesarean section (C-section) deliveries carried out during labor and certain risks in subsequent pregnancies.
Over the past few decades, C-section rates have been on a steady upward climb across the globe. Between 1990 and 2014, the global C-section rate witnessed a 12.4% increase. In England, the situation is particularly notable, as more than one-third of women are now delivering via C-section. Among these procedures, approximately 24% are emergency ones, and 5% occur when the cervix is fully dilated. In North America, the rate of full dilatation C-sections has seen a significant 44% surge in the last decade.
Multiple factors are contributing to this growing trend. Shifts in clinical and professional training methods, concerns regarding litigation, and the changing cultural and social expectations all play their part. While C-sections can indeed be crucial in saving lives during pregnancy complications, the increasing frequency of their use, especially in emergency circumstances, has led to concerns about the long-term effects on both maternal and fetal health.
Emergency C-section procedures, especially those taking place late in the labor process, have been associated with negative outcomes in subsequent pregnancies. Observational studies have strongly indicated that in-labor C-sections are linked to an elevated risk of spontaneous preterm birth (sPTB) as well as mid-trimester pregnancy loss.
The risks become even more pronounced when the cervix is more dilated at the time of the surgery, reaching their peak when it is fully dilated. For the majority of women who have had an in-labor C-section, the risk of preterm birth in a future pregnancy remains relatively low, typically less than 5%. However, those women who experience preterm birth after an in-labor C-section are more likely to face recurrent preterm births in their subsequent pregnancies.
Recent analysis has shown that women who had an in-labor C-section and then had a preterm birth were 2.7 times more likely to experience recurring sPTB compared to women with other preterm birth risk factors. When it comes to mid-trimester losses, the relative risk jumps to 5.65. In one cohort studied, 54% of women who had a preterm birth following an in-labor C-section went on to have another preterm delivery in a subsequent pregnancy, a rate that is considerably higher than that of other high-risk groups.
The association observed between in-labor C-sections, sPTB, and mid-trimester loss can potentially be explained by cervical damage that occurs during the surgery. The cervix plays a vital role in preventing premature labor. During the advanced stages of labor, surgical interventions often involve incisions close to or within the cervical tissue, which increases the likelihood of trauma.
As labor progresses and the fetus’s head descends into the pelvis, performing a surgical delivery becomes more challenging. This can lead to a higher risk of cervical injury due to surgical extensions, sutures, or infections, ultimately compromising the integrity of the cervix. Advanced imaging techniques like transvaginal ultrasound (TVUS) have provided further understanding of the role of cervical damage, as cesarean scars can be seen as disruptions in the uterine wall.
Standard interventions aimed at preventing sPTB, such as transvaginal cerclage (TVC), are not as effective for women who have previously undergone in-labor C-sections. In TVC, a suture is placed in the cervix during early pregnancy to reduce the risk of preterm labor. However, among women with a history of in-labor C-sections, the failure rates of TVC are high. One study found that these women were ten times more likely to give birth before 30 weeks of gestation than women with other risk factors. In the same analysis, 46% of the women with prior in-labor C-sections and who had received TVC experienced either sPTB or mid-trimester loss.
For women with cervical damage resulting from in-labor C-sections, transabdominal cerclage (TAC) may offer a viable alternative. TAC bypasses the damaged cervical tissue and provides better protection than TVC. A retrospective cohort study demonstrated that TAC significantly reduced sPTB rates before 30 weeks when compared to TVC, with an odds ratio of 0.09. This indicates that TAC could be a valuable option for women with a history of in-labor C-sections, especially those dealing with recurrent preterm births.
C-sections are the most common surgical procedure globally, affecting nearly a quarter of all women. The potential for cervical damage during in-labor C-sections and its implications for future pregnancies highlight the importance of having tailored management strategies in place. Clinicians and patients alike must be aware of these risks and collaborate through shared decision-making to ensure better outcomes for both mothers and fetuses.
The link between in-labor C-sections, mid-trimester losses, and sPTB has emerged as a significant clinical problem. With the increasing prevalence of in-labor C-sections, there is an urgent need to address this issue. This can be achieved through improved training in instrumental delivery and labor management. Further research is also essential to gain a deeper understanding of the mechanisms behind cervical damage and to develop strategies to minimize harm.
Moreover, enhanced imaging protocols could play a critical role in identifying women at risk and guiding treatment decisions. Additionally, evaluating the effectiveness of interventions like TAC in preventing adverse outcomes will be valuable in informing future clinical guidelines.
Related topics
- Short Daily Reflection Sessions Help Health Care Workers Combat Burnout
- Study Identifies Structural and Functional Brain Changes in Opioid Use Disorder
- Study Highlights Ableism as a Barrier to Mental Health Care for Disabled Individuals
