Perfluoroalkyl substances exposure in early pregnancy and preterm birth in singleton pregnancies: a prospective cohort study

Table 4 Associations between PFAS concentrations in early pregnancy and preterm birth

PFAS (ng/ml)	Overall preterm birth		Spontaneous preterm birth		Indicated preterm birth
	N_preterm = 136/N_term2713		N_preterm = 97/N_term = 2713		N_preterm = 39/N_term = 2713
	OR (95% CI)	aOR^a (95% CI)	OR (95% CI)	aOR^a (95% CI)	OR (95% CI)	aOR^a (95% CI)
PFOA	0.93 (0.62, 1.40)	0.92 (0.61, 1.33)	0.74 (0.45, 1.20)	0.73 (0.45, 1.19)	1.63 (0.78, 3.39)	1.71 (0.80, 3.67)
PFNA	0.85 (0.61, 1.18)	0.86 (0.61, 1.20)	0.81 (0.55, 1.19)	0.82 (0.56, 1.22)	0.94 (0.52, 1.71)	0.99 (0.53, 1.86)
PFDA	0.86 (0.65, 1.14)	0.88 (0.66, 1.17)	0.79 (0.57, 1.10)	0.80 (0.58, 1.12)	1.06 (0.64, 1.76)	1.14 (0.67, 1.93)
PFUA	0.79 (0.59, 1.05)	0.82 (0.61, 1.10)	0.77 (0.55, 1.07)	0.78 (0.56, 1.10)	0.83 (0.50, 1.41)	0.93 (0.54, 1.61)
PFOS	0.88 (0.64, 1.19)	0.86 (0.63, 1.17)	0.79 (0.55, 1.14)	0.77 (0.53, 1.11)	1.12 (0.65, 1.95)	1.13 (0.64, 2.01)
PFHxS	1.16 (0.80, 1.69)	1.16 (0.79, 1.71)	1.05 (0.67, 1.65)	1.03 (0.65, 1.63)	1.45 (0.76, 2.69)	1.58 (0.82, 3.05)
PFHpA	0.96 (0.80, 1.16)	0.95 (0.78, 1.15)	0.93 (0.74, 1.16)	0.91 (0.72, 1.14)	1.04 (0.74, 1.47)	1.06 (0.74, 1.53)
PFBS	1.09 (0.85, 1.39)	1.06 (0.83, 1.37)	0.94 (0.70, 1.26)	0.93 (0.69, 1.25)	1.49 (0.96, 2.32)	1.44 (0.91, 2.26)
PFDoA	0.71 (0.50, 1.01)	0.73 (0.51, 1.04)	0.82 (0.66, 1.01)	0.82 (0.66, 1.03)	0.73 (0.39, 1.35)	0.82 (0.53, 1.58)

Note: PFAS concentrations were measured in maternal plasma and have been ln-transformed before entering into the model
^a Adjusted for maternal age (years), pre-pregnancy BMI (kg/m²), parity (0, ≥ 1), parental educational levels (≤ 12, > 12 years), pregnancy complicating with chronic diseases (no, yes), infant sex (male, female) and gestational age at blood drawn (weeks)

ISSN: 1476-069X