Prenatal exposure to polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) may influence birth weight among infants in a Swedish cohort with background exposure: a cross-sectional study

Table 3 Associations between exposure to di- ortho PCBs and PBDEs and birth weight

	β^a	SE^b	p	N
Unadjusted model^c
di-ortho PCBs^d	−26	44	0.6	411
di-ortho PCBs^d - restricted^e	2	48	1.0	346
PBDE(4)^f	−49	40	0.2	362
PBDE(4)^f – restricted^e	−47	42	0.3	346
Multivariate model^g
di-ortho PCBs^d	137	61	0.02*	346
di-ortho PCBs^d - restricted^h	131	74	0.08	254
PBDE(4)^f	−54	46	0.2	346
PBDE(4)^f – restricted^h	−117	59	0.05*	254
Multivariate model including gestational lengthⁱ
di-ortho PCBs^d	143	65	0.03*	254
PBDE(4)^f	−106	52	0.04*	254

^aRegression coefficient, i.e. change in birth weight per 1-unit increase in ln-transformed contaminant concentration in breast milk.
^bStandard error.
^cDi-ortho PCB and PBDE(4) were included in separate models.
^dSum of PCB 138, PCB 153 and PCB 180.
^eRegression analysis restricted to individuals with data on all covariates included in the multivariate model.
^fSum of BDE-47, BDE-99, BDE-100 and BDE-153.
^gDi-ortho PCB and PBDE(4) were included in the same model. Other covariates included were age of the mother, pre-pregnancy BMI, weight gain during pregnancy, education, smoking and infant sex.
^hMultivariate regression analysis restricted to individuals with data on gestational length.
ⁱGestational length was added to the covariates in the multivariate model.
*p≤0.05.

ISSN: 1476-069X