Can't really answer the question directly. But methadone can have an impact apparently on sperm motility. Not that this means either yes or no to the question of fertility or rule out other causes. Just something to ask a doctor about. From the New England Journal of Medicine (couldn't find the full article):
The function of the secondary sex organs was found to be markedly impaired in 29 participants in a methadone maintenance program. The ejaculate volume and seminal vesicular and prostatic secretions were reduced by over 50 per cent in methadone clients, as compared to 16 heroin addicts and 43 narcotic-free controls. Serum testosterone levels were also approximately 43 per cent lower in methadone clients than in controls or heroin users. Although the sperm count of methadone clients was more than twice the control levels, reflecting a lack of sperm dilution by secondary-sex-organ secretions, the sperm motility of these subjects was markedly lower than normal. On all measures of secondary-sex-organ and testicular function, heroin addicts appeared to fall between the methadone and control subjects, but, with the exception of sperm motility, the deviation from control values did not reach statisitcal significance."
From the fertility aspect 6 months is a relatively short amount of time to try .I know its very frustrating. I went threw it no doctor would even see us until we had tried for 24 months .I ended up needing some help but had my wonderful son .Give it some time .....Let nature take it course I bet it will happen :)
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