Fertility study puts phthalates back under the spotlight

Scientists have published research findings that point to possible implications to ovarian response to IVF treatment, bringing further debate to the effect they can have on human fertility.

Phthalates are a large class of compounds, some of which are found in cosmetic products such as fragrances, hairspray and nail varnishes and serve to either hold colour or as scents.

However, over the years they have been bought into question over speculation that they can effect fertility in both men and women because they are thought to be endocrine disruptors, which some suggest is part of the reason for a decline in fertility rates in developed regions.

Research findings concentrate on how phthalates influence female reproduction

At the recently held annual meeting for the European Society of Reproduction and Embryology, a group of scientists presented their research findings which focused on the effects of phthalates on female reproduction, contrary to conventional research which has focused on male fertility.

The report was presented by Dr. Irene Souter of Massachusetts General Hospital and Harvard Medical School, Boston, and suggests that exposure to phthalates – measured by phthalate metabolites in urine – is associated with reduced fertility during IVF treatment.

"Our data support the hypothesis that exposure to specific phthalates might lead to adverse female reproductive outcomes," said Dr Souter.

Study involved a large group of women undergoing IVF

The study followed the progress of 231 women scheduled for IVF at the Massachusetts General Hospital between 2004 and 2012; urine samples were taken at the start of and throughout treatment and analysed for metabolites of four primary phthalates.

Although phthalates are a broad group of compounds, their use can be divided into two principles groups – those with a higher density, which are commonly used in the production of plastics, and those that have a lower density, which are more often used in cosmetics formulation.

In the presentation, Souter referred specifically to some examples of DEHP, a phthalate that is found in plastic products, as well as other phthalates used in cosmetic products. Her research found that higher levels of DEHP in urine samples were linked with IVF implantation failure.

Phthalates are widespread and may adversely effect female fertility

Souter rounded off her presentation by stating her belief that phthalates are widespread in the environment and ‘may well have an adverse effect on female fertility.

"We are all primarily exposed to phthalates through inhalation and ingestion," she explained. "It is extremely difficult if not impossible to avoid exposure to phthalates, since they are in so many products," she said.

The presentation was rounded off by Souter suggesting that ways of avoiding exposure to phthalates included reducing exposure to certain personal care and fragrance products, as well as certain types of plastic packaging food and reading labels on babies toys to avoid use of vynils.