Prophylactic antibiotics for women with planned caesarean section reduces risk of postpartum antibiotics: Study

Since no national recommendation for antibiotic prophylaxis for planned CS in Sweden exists, the Swedish delivery units have chosen different strategies. Some units routinely administer antibiotic prophylaxis to all women for whom a CS is planned, while other units give prophylactic antibiotics to risk groups only. In the absence of recent randomized trials, authors K. Dahlquist et al. took advantage of this “natural experiment” to compare the risk of maternal antibiotic prescription for treatment postpartum between women who gave birth at hospitals that routinely administrated prophylaxis versus hospitals with a risk-based strategy.

This was an observational study based on data from Swedish registers. The population is based on women giving birth by planned caesarean section from 37 + 0 weeks of gestation, 2014–2020 (n = 7308). The risk of antibiotic prescription postpartum was compared between women who delivered in hospitals with a general routine of administrating antibiotics (n = 5637) for planned CS and women who delivered in hospitals administrating prophylaxis in conjunction with planned caesarean section to risk groups only (n = 1671). Antibiotic postpartum was defined as a prescription of antibiotics postpartum 2–42 days after planned caesarean section.

No difference in antibiotic prescription postpartum among women in hospitals with a general routine of prophylaxis, compared to women in hospitals with a risk-based strategy was found, RR: 1.18 (95 % CI 0.99–1.40). Women with identified risk factors (diabetes/gestational diabetes and/or BMI > 30), were more likely 1.52 (95 % CI 1.03–2.25) to receive a prescription postpartum in hospitals with a general routine of antibiotic prophylaxis than women delivered at hospitals with risk-based strategy.

This study, including over 7000 planned CSs, showed no protective effect of routinely administrated prophylactic antibiotics compared to a risk-based strategy, on postpartum antibiotic. On the contrary, women with risk factors such as diabetes or obesity were at higher risk of a prescription of antibiotics for treatment postpartum if they were delivered in units with a general prophylactic regimen than in units with a risk-based strategy. However, the overall difference in proportion was quite small.

In this register-based study, based on deliveries in modern high technology units, authors found no evidence that routinely administrated prophylactic antibiotics for women with planned CS reduces the risk of a prescription of antibiotics for treatment postpartum. In hospitals with routinely administrated prophylactic antibiotics, 11 % of the women were prescribed postpartum antibiotics compared to 9 % among women delivered in hospitals with a risk-based regimen (Adjusted RR 1.16; 95 % CI: 0.98–1.38). Among women with diabetes and/or obesity, they found higher rates of postpartum prescription of antibiotics for those women delivered in hospitals with a general compared with risk-based regimen (12 % and 8 %, respectively, adjusted RR 1.52; 95 %CI: 1.03–2.24). Thus, authors found evidence that the prophylactic antibiotic rate is associated with the post-partum antibiotic prescription rates and speculate that this reflects attitudes rather than complication rates. The negative results may contribute to the literature regarding different prophylaxis strategies, especially considering the WHO global strategy for containment of antimicrobial resistance, underscoring the importance of appropriate prescription of antibiotics.

Source: K. Dahlquist et al.; European Journal of Obstetrics & Gynecology and Reproductive Biology 304 (2025) 121–126