Plastiser increases miscarriage risk.

In a new study, the first of its kind, researchers have studied couples trying to conceive a child for the first time and found that women with greater exposure to a phthalate associated with plastics were more likely to experience a pregnancy loss. Scientists in Denmark report that women exposed near the time of conception to relatively common levels of a particular phthalate are more likely to experience early pregnancy loss compared to women with lower exposures. The phthalate associated with the losses is a breakdown product of a phthalate highly used in plastics. Only exposures around conception – and not in the prior month – were linked to the loss. This is the first study to examine phthalate exposure and miscarriage in humans. It is unique because it measured exposures at a specific time after conception that is an important window for early pregnancy loss. The results are published in the journal Environmental Health Perspectives. Rodent studies also report reproductive effects of phthalate exposure. Prior research shows phthalates can cause pregnancy loss and reduced litter size. The animals in these studies were exposed to phthalate levels about 100 times greater than those experienced by the general human population. Adults are exposed to phthalates primarily through diet. Phthalates are used to make vinyl plastics softer and more flexible. Food packaging, medical tubing and children’s toys can contain the chemicals. Other phthalates are also found in certain personal care products, such as fingernail polish, perfumes and cosmetics. Because of their wide use, exposure is ubiquitous and continuous. Approximately one-third of all pregnancies end before term. Many are lost during the first weeks of pregnancy before a woman may even know she is pregnant. From 1992 to 1994, couples in Denmark trying to get pregnant for the first time participated in the study by donating daily urine samples. In 2009, researchers analysed the samples for levels of a hormone called hCG (human chorionic gonadotropin), which is the same hormone that home pregnancy tests can detect. The scientists identified early pregnancy losses in the women by determining who had high levels followed by a decline of hCG in their urine. For pregnancies that were confirmed by a doctor, the women reported their pregnancy outcome after one year. In addition, the researchers analysed the urine samples taken shortly before ovulation for concentrations of several phthalates and the metabolites of these phthalates, which are excreted in the urine after the body has processed the chemical. The results showed that of the 148 women followed, 48 had a pregnancy loss, of which 32 were early on and identified by fluctuating hCG hormone levels. The women in this study were exposed to phthalates at the same levels as women in other parts of the world, such as Germany and the United States. The scientists found that the women with the highest levels of monoethylhexyl phthalate (MEHP) in their urine around the time of conception were more likely to experience a pregnancy loss compared to those with lower exposures. The associated risk was greatest when the scientists considered only early pregnancy losses occurring within the first six weeks of gestation. High levels of MEHP indicate a greater exposure to the particular phthalate di-(2 ethylhexyl) phthalate (DEHP), which is a component in plastics. The scientists only detected the association when they considered phthalate exposure during the month that conception occurred. Phthalate exposure from the previous month before pregnancy had no detectable effects in terms of pregnancy loss. Since this study is the first of its kind in humans, further studies are necessary to confirm the relationship between phthalate exposure and pregnancy losses.

Environmental Health News, 12 January 2012 ; ;