Prelabor cesarean section: the role of advanced maternal age and associated factors

to evaluate whether advanced maternal age (AMA) is associated with prelabor cesarean section and to identify the factors associated with prelabor cesarean section in AMA women, according to the mode of type of labor financing (private or public).

Based on the Birth in Brazil survey, the research was conducted on representative sample of mothers for the country (Brazil), regions, type of hospital and location (capital or not), in 2011/2012. This study included 15,071 women from two age groups: 20-29 years and ≥ 35 years. The information was collected from interviews with puerperal woman, prenatal cards, and medical records of mothers and newborns. Multiple logistic regression modelling was used to verify the association between prelabor cesarean section and maternal, prenatal and childbirth characteristics, according to the mode of financing.

Our results showed a higher use of prelabor cesarean section for AMA (≥ 35 years) women in the public service (OR = 1.63; 95%CI 1.38-1.94) and in the private service (OR = 1.44; 95%CI 1.13-1.83), compared with women aged 20-29 years. In the adjusted model, we recorded three factors associated with the prelabor cesarean section in AMA women in both, public and private sectors: the same professional in prenatal care and childbirth (OR = 4.97 and OR = 4.66); nulliparity (OR = 6.17 and OR = 10.08), and multiparity with previous cesarean section (from OR = 5.73 to OR = 32.29). The presence of obstetric risk (OR = 1.94; 95%CI .44-2.62) also contributed to the occurrence of prelabor cesarean section in women who gave birth in the public service.

AMA was an independent risk factor for prelabor cesarean in public and private services. In the public, prelabor cesarean in AMA was more influenced by clinical criteria. Higher chance of prelabor cesarean section in nulliparous women increases the chance of cesarean section in multiparous women, as we showed in this study, which increases the risk of anomalous placental implantation.