Dr Soriah Harvey1,2, Dr Megan Jensen1,2, Dr Annelies Robijn1, Prof Michael Peek3, Breathing for Life Trial Collaborative group, Prof Peter Gibson1,2,4, A/Prof Vanessa Murphy1,2
1School of Medicine and Public Health, University of Newcastle, Newcastle, Australia, 2Asthma and Breathing Research Program, Hunter Medical Research Institute, Mayfield, Australia, 3Australian National University, Canberra, Australia, 4Department of Respiratory & Sleep Medicine, John Hunter Hospital, Newcastle, Australia
Biography:
Dr Harvey is an early career researcher with a background in Nutrition & Dietetics. Her thesis examined the role of key modifiable nutritional risk factors during pregnancy and early life, with a focus on vitamin D and breastfeeding, in preventing adverse infant respiratory health outcomes in high-risk infants.
Abstract:
Background: Maternal Asthma is associated with higher rates of adverse perinatal outcomes, including caesarean birth, but the mechanisms are unknown. Maternal characteristics, including asthma-related variables, may be associated with caesarean birth.
Aim: To examine the prevalence, indications, and maternal characteristics associated with caesarean birth among a cohort of pregnant women with asthma in Australia.
Method: Data from women with asthma was obtained from the Breathing for Life Trial and its Nutrition sub-study pregnancy cohorts. Maternal characteristics were collected from study visits. Mode of birth was collected via electronic medical records. Potential factors associated with caesarean birth in women with asthma were examined using logistic regression adjusting for confounders (body mass index, advanced maternal age, socioeconomic status, birth hospital).
Result: Of n=1281 participants, n=445 (34.8%) of births were by caesarean birth. Advanced maternal age (≥35yrs) (aOR 1.65 95%CI 1.24-2.22), overweight (aOR 1.41 95%CI 1.03-1.94) or obesity (aOR 2.0 95%CI 1.51-2.73), hypertension in pregnancy (aOR 1.85 95%CI 1.11-3.08), preeclampsia (aOR 2.53 95%CI 1.21-5.30 ), multiple pregnancy (aOR 5.24 95%CI 2.84-9.67) and excessive gestational weight gain (aOR 1.86 95%CI 1.39-2.49) were associated with increased odds of caesarean birth, whilst use of short-acting beta-agonists (SABA) at baseline (~18 week’s gestation) reduced the odds (aOR 0.52 95%CI 0.30-0.90). Other asthma-related factors (inhaled corticosteroid use, control, lung function, and exacerbations) were not associated with caesarean birth.
Conclusion: Several maternal characteristics were associated with increased odds of caesarean birth in this cohort of women with predominantly mild asthma. The rate of caesarean birth is significantly higher than WHO recommendations. Targeting modifiable factors associated with caesarean birth such as maintaining a healthy weight prior to and during pregnancy, may reduce the impact of adverse perinatal outcomes in this group. Further examination of the mechanisms linking maternal asthma with caesarean birth is warranted.
Keywords
asthma: pregnancy: caesarean