Fertility treatment success rates are significantly influenced by mother's ethnicity

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Ethnicity of the mother is a significant determinant of successful outcomes after fertility treatment according to a new study by researchers at Nottingham University’s Research and Treatment Unit in Reproduction (NURTURE).

The team conducted a study to assess the relationship between the ethnicity of patients and the clinical success of their fertility treatment. The research is published in BJOG: An International Journal of Obstetrics and Gynaecology .

The study analysed data from 1,517 women in the UK undergoing their first cycle of fertility treatment, including in-vitro fertilisation (IVF) or intro-cytoplasmic sperm injection (ICSI). 85.1% were White Europeans and 14.9% from an ethnic minority group.

Realistic probabilities

The data was gathered between 2006 and 2011. It was analysed for live birth outcomes (defined as a viable infant born after 24 weeks of gestation) and showed that when compared to White European women, the live birth rates of ethnic women were significantly lower, at 35% compared to 43.8%.

A similar trend was also found for clinical pregnancy rates and implantation rates, with White European women again showing significantly higher rates than women from ethnic minorities, 47.9% vs 38.5% and 37.4% vs 22.6% respectively.

The paper concludes that these results will help clinicians counsel couples about their realistic probabilities of a positive outcome after fertility treatment. As a result of these findings, the researchers are now examining data from the national patient’s register held by the Human Fertilisation and Embryology Authority (HFEA) to extend the analysis of the different cohorts of ethnicities and their success rates after assisted reproductive treatment.

Dr Walid Maalouf from NURTURE, Division of Child Health, Obstetrics and Gynaecology , Faculty of Medicine & Health Sciences University of Nottingham, and lead researcher on the paper said:

“Our data indicates that live birth rates, clinical pregnancy rates and implantation rates following fertility treatment, particularly IVF, are significantly lower in ethnic women when compared to White Europeans.

“The reason for the reduced implantation rates and subsequent reduced outcomes in the ethnic minority group is still unclear. Further research is needed into genetic background as a potential determinant of IVF outcome, as well as the influencing effects of lifestyle and cultural factors on reproductive outcomes.

“Subsequently, these findings could be used to modify clinical strategies in fertility treatments to increase success rates among all ethnic minority groups.”

Individualised success rates

Co-author and clinical director of NURTURE, Mr James Hopkisson said: “I agree that this data provides an interesting insight into individualised success rates, which will help focus research strategies into improving IVF outcome to different ethnic groups.

“It is NURTURE’s aim to help all couples to achieve a successful live birth. This study shows that we need to make sure that we look for factors that may decrease implantation and increase early pregnancy loss due to ethnicity. The next step then is to find interventions to improve outcome.”

John Thorp, BJOG deputy editor-in-chief, added: “We know that the main aim of couples undergoing fertility treatment is to achieve a healthy baby and findings from this study are helpful in understanding that ethnicity may be a significant indicator for success following such treatment.

“It is important that women are fully aware of their realistic chances of success when undergoing any form of assisted reproductive therapy and this information could help clinicians better inform and counsel patients.

“Furthermore, evidence of more realistic success rates of women undergoing fertility treatment could be used to encourage women from ethnic backgrounds to seek treatment earlier and improve the likelihood of a positive pregnancy outcome.”