Table III.

Studies of obstetrics and gynaecology

Study	Contaminant	Outcome	Population	Results*
Dallaire (55)	PCBs, HCB and Hg	Foetal Growth and pregnancy duration	Pregnant women (n = 248) (participation rate: 59%)	Cord PCB-153, HCB and Hg Duration of pregnancy: Inverse association (β = − 0.17 to −0.20) Fatal growth (mediated through shorter gestation period): Inverse association for length (β = − 0.16 to −0.18 for PCB-153 and HCB respectively)
Wojtyniak (56)	PCBs and p,p′-DDE	Birth weight, gestational age and preterm birth	Women with singleton live births (n = 572) (participation rate: 86%)	PCB-153 Birth weight: Inverse association (β = − 59.2, 95% CI: −100.6 to −17.8) Gestational age: Inverse association (β = − 0.2, 95% CI: −0.4–0.0) p,p′-DDE Birth weight: Inverse association (β = − 39.4, 95% CI: −79.0–0.2) Gestational age: Inverse association (β = − 0.2, 95% CI: −0.4–0.0) No association with preterm birth
Dallaire (57)	PCBs, HCB and PCP	Thyroid hormone levels	Pregnant women (n = 107) and infants up to 7 months of age (n = 130)	Thyroid hormone levels in women at delivery:   Maternal PCB hydroxylated metabolites T3: Positive association (β = 0.57) No association with other thyroid hormones  Maternal PCB-153, HCB and PCP: No association Thyroid hormone levels in umbilical cord:  Maternal and cord PCB-153 TBG: Inverse association (β = − 0.25 for maternal PCB-153 and −0.26 for cord PCB-153) No association with other thyroid hormones  Maternal PCP fT4: Inverse association (β = − 0.59) No association with other thyroid hormones  Maternal or cord HCB and PCB hydroxylated metabolites/cord PCP: No association Infant PCB-153 or HCB: No association
Toft (58)	PCBs and p,p′-DDE	Menstrual cycle	Pregnant women presenting for antenatal care at local hospitals (n = 454) (participation rate: 90%)	PCB-153 Long menstrual cycles: Inverse association (OR = 0.7, 95% CI: 0.5–0.96) No association with average cycle length, irregular cycles, or short cycles p,p′-DDE Long menstrual cycles: Inverse association (OR = 0.7, 95% CI: 0.5–0.99) No association with average cycle length, irregular cycles, or short cycles
Lucas (59)	PCBs and Hg	Birth weight and gestational age	Pregnant women (n = 491) (participation rate: 30% for gestational age outcome)	Cord PCB-153 Birth weight: Positive association in unadjusted analysis Hg: No association
Muckle (60) (Abstract only)	PCBs, OCPs and Hg	Developmental effects	Not provided	OCs Physical growth at birth: Inverse association (estimate not provided) Duration of pregnancy: Inverse association (estimate not provided) Hg: No information provided
Pereg (61)	PCBs	Placental CYP1A1 activity	Pregnant women admitted to hospital upon delivery (n = 35)	No association
Lagueux (62)	PCBs and OCPs	Placental CYP1A1 activity and DNA adducts	Women giving birth in regional hospitals (n = 22)	PCB-153, p,p′-DDE, HCB CYP1A1 activity: Positive association in moderate smokers (R2=0.21, 0.51, 0.38 respectively) PCB-118 CYP1A1 activity: Positive association in heavy smokers (R2=0.30) Associated with bulky DNA adduct formation in non-smokers and moderate smokers across all cohorts, including non-Inuit p,p′-DDE Associated with less bulky DNA adducts across all cohorts, including non-Inuit
Foldspang (63)	Hg	Gestational length and birth weight	Mothers with singleton deliveries (n = 376) (participation rate: 45.9% newborns represented from one district)	Birth weight: Inverse association (β = − 7.1 for maternal blood mercury and −4.2 for offspring blood mercury) No association with gestational length

CI=confidence interval; DDE=dichlorodiphenyldichloroethylene; DNA=deoxyribonucleic acid; fT₄=free thyroxine; HCB=hexachlorobenzene; Hg=mercury; OCs=organochlorines; OCPs=organochlorine pesticides; OR=odds ratio; PCBs=polychlorinated biphenyls; PCP=pentachlorophenol; T₃=triiodothyronine; TBG=thyroxine-binding globulin.

^*Adjusted estimates are presented where available. Presented estimates are statistically significant at p ≤ 0.05 level.