Assessment of fluoride levels during pregnancy and its association with early adverse pregnancy outcomes

BACKGROUND AND AIM: There is sparse data available on human subjects regarding the affect of excessive fluoride exposures on pregnancy. The aim of this study was to examine the association between elevated urinary fluoride levels during early pregnancy and maternal anemia and adverse fetal outcome. PATIENTS AND METHODS: We enrolled 600 pregnant patients with gestational age less than 20 weeks and with a high urinary fluoride levels(>1 mg/L).We also documented the fluoride levels in the tap water and ground water samples collected from the areas where these women resided during pregnancy. These patients were also evaluated for hemoglobin levels and detailed fetal examination by ultrasound. Data was assessed by SSPS version 16.0 software and P < 0.05 was considered to be significant. RESULTS: Urinary fluoride averaged 2.65 mg/L and ranged from 1.0 to 4.3 mg/L while all the water samples revealed fluoride levels greater than WHO prescribed the limit of 1.5 mg/L. A total of 402 patients (67%) were found to be anemic with hemoglobin levels ranging from 6.2 to 11.9 g/dl (9.28 ± 1.29). Eighty one patients (13.5%) had adverse fetal outcomes that comprised abortions, congenital abnormalities, and intrauterine deaths (IUDs). There was a negative correlation between urinary fluoride and hemoglobin levels (P = 0.031, r= -0.59) and females with elevated urinary fluoride levels were found to have a strong association with the pregnancy complications, i.e., anemia, miscarriage, abortion, and still birth (χ(2) = 9.23, P < 0.05). CONCLUSIONS: Excess fluoride exposures can have deleterious effects on the expecting mother and fetus and is associated with adverse pregnancy outcomes.