Newswise — WASHINGTON – A first-of-its-kind study indicates that male partners of women with recurrent pregnancy loss have reduced sperm quality caused by impaired reproductive hormone production and high oxidant levels. This research, published in the Men’s Health Issue of AACC’s Clinical Chemistry journal, could help more couples with recurrent pregnancy loss to conceive by leading to new treatments that improve male partners’ reproductive health. 

Recurrent pregnancy loss affects 1-2% of couples and is classically defined as three or more consecutive miscarriages. Women with recurrent pregnancy loss are routinely screened and treated for causative factors, but in about 50% of cases, testing fails to reveal an underlying cause, making it difficult to determine what medical interventions will help. One potential reason for these unexplained miscarriages is reduced sperm quality in male partners, which recent studies have observed. The reasons behind low sperm quality in cases of recurrent pregnancy loss are still unclear, however, and must be elucidated before routine screening can be implemented and treatments developed for male partners. 

A team of researchers led by Waljit S. Dhillo, PhD, of Imperial College London, Hammersmith Hospital, has shown for the first time that these men not only have reduced sperm quality but also low reproductive hormone levels. The researchers found this by comparing several reproductive parameters between 50 male partners of women with recurrent pregnancy loss and 63 healthy men. From this comparison, Dhillo’s team determined that testosterone and estradiol levels were, respectively, 15% and 16% lower in the recurrent pregnancy loss group than in the healthy group. The recurrent pregnancy loss group also exhibited reduced sperm motility and abnormal sperm morphology. As both testosterone and estradiol play essential roles in sperm development, these results suggest that impaired reproductive hormone production is leading to the low sperm quality seen in the recurrent pregnancy loss group. 

In addition, the researchers found that men in the recurrent pregnancy loss group had two-fold higher levels of sperm DNA fragmentation and four-fold higher mean levels of oxidants than the healthy men. These results are significant because sperm DNA plays a critical role in the formation of the placenta, and Dhillo’s team’s finding supports previous studies that have implicated oxidative stress as a cause of sperm DNA fragmentation. When taken together, all of these findings indicate that management of recurrent pregnancy loss could be improved if male partners are tested and treated for low reproductive hormone levels and high oxidant levels.  

“Our data have important implications for the management of couples with [recurrent pregnancy loss],” said Dhillo. “Endocrine and molecular sperm profiling may offer a potential novel approach to stratifying future miscarriage risk. Further studies will investigate whether endocrine and molecular sperm abnormalities may be ameliorated by lifestyle, dietary, and hormonal interventions to optimize chances of successful conception in couples with [recurrent pregnancy loss].” 

About AACC

Dedicated to achieving better health through laboratory medicine, AACC brings together more than 50,000 clinical laboratory professionals, physicians, research scientists, and business leaders from around the world focused on clinical chemistry, molecular diagnostics, mass spectrometry, translational medicine, lab management, and other areas of progressing laboratory science. Since 1948, AACC has worked to advance the common interests of the field, providing programs that advance scientific collaboration, knowledge, expertise, and innovation. For more information, visit

Clinical Chemistry is the leading international journal of clinical laboratory science, providing 2,000 pages per year of peer-reviewed papers that advance the science of the field. With an impact factor of 8.636, Clinical Chemistry covers everything from molecular diagnostics to laboratory management.



Journal Link: Clinical Chemistry, Jan-2019