Perinatal outcomes in women with cystic fibrosis: Data from the Italian Cystic Fibrosis Registry

Abstract

Introduction: Data from the Italian Cystic Fibrosis Registry concerning pregnancies in the period 2010-2015 were used to investigate the association between the preconception clinical status and perinatal outcomes of women with cystic fibrosis (CF).

Material and methods: The assessed clinical variables were genotype, age at the time of conception, body mass index (BMI) and the percentage of predicted forced expiratory volume in the first second (ppFEV₁ ). The analyzed outcomes were gestational age, birthweight and the frequency of cesarean deliveries. A generalized linear mixed model (GLIMMIX) was used to evaluate the association between type of delivery and age at the time of becoming pregnant, BMI, ppFEV₁ and gestational age. Robust multivariable regression was used to evaluate the relation between gestational age and age at the time of becoming pregnant, BMI and ppFEV₁ . Multivariable linear regression was performed to verify association between birthweight and BMI, and ppFEV₁ .

Results: Complete information concerning mother and child was available for 56 completed pregnancies. Median age at the time of conception was 30.8 years (range: 18.7-42.3); median BMI was 21.5 kg/m² (range: 16.5-26.8); and median ppFEV₁ was 73.9 (range: 30-128). In all, 31 women (55.36%) had a genotype consisting of two CF-causing variants. Eight were homozygous for the F508del mutation (14.28% of the total). The median duration of pregnancy was 37 weeks (range: 31-41) and the frequency of prematurity (<37 weeks of gestational age) was 28.30%. Median birthweight was 2910 g (range: 1300-3650). The overall frequency of cesarean sections was 63.64%. A low preconception ppFEV₁ was associated with prematurity (p = 0.014), and birthweight was positively related to ppFEV₁ (p = 0.04). There was no association between the clinical variables or gestational age and the type of delivery.

Conclusions: Maternal preconceptional respiratory function correlates with the duration of pregnancy and the birthweight of newborns. Cesarean deliveries are also frequent among young women with CF with normal respiratory function.

Keywords: birthweight; cesarean delivery; cystic fibrosis; cystic fibrosis registry; pregnancy outcomes.