Danish pregnancy cohort suggests that in utero exposure to PFOA could be associated with lower levels of sperm concentration and total sperm count in adult males, reduced testicular size, and higher adjusted levels of luteinizing hormone and follicle-stimulating hormone. In utero PFOA exposure is also demonstrated to impact female development. For example, a study following a Danish population-based cohort found a 5.3 month later age of menarche in girls exposed to higher levels of PFOA in utero. Delayed onset of menarche is associated with lower bone mineral density and may have psychosocial impacts. Other impacts on exposure in utero PFOA exposure on thyroid function has also been a topic of concern, and has found to negatively impact thyroid stimulating hormone even at low levels when exposed during fetal development. PFOA is also shown to have obesogenic effects, and an experimental study found a positive correlation to low-dose prenatal exposure of PFOA and prevalence of overweight and high waist circumference in females at age 20. A correlation between in utero PFOA exposure and mental performance has yet to be established, as many studies have resulted in insignificant results. For example, a study conducted near Parkersburg, West Virginia did not find a significant association between in utero PFOA exposure and performance of math skills or reading performance in children ages 6 to 12 living in the PFOA-contaminated water district. Based on a cohort study conducted in the Mid-Ohio Valley, no clear association was found between prenatal exposure to PFOA and birth defects, although a possible association with brain defects was observed and requires further research and assessment. PFOA has been associated with signs of reduced fetal growth including lower birth weight. However, other studies have not replicated the lower birth weight finding including a study on the DuPont exposed community. Extrapolated epidemiological data suggests a slight association between PFOA exposure and low birth weight. This was consistent based on blood levels of PFOA metabolites regardless of the geographic residence of subjects. Generally, the findings among human fetuses exposed to the chemical were considerably less drastic than what was seen in mice studies. Because of this, studies linking exposure to low birth weight can be considered inconclusive. PFOA exposure in the Danish general population was not associated with an increased risk of prostate, bladder, pancreatic, or liver cancer. Maternal PFOA levels were not associated with an offspring's increased risk of hospitalization due to