For 2 Years My Partner Has Been Taking 5mg Amlopodine

For 2 years my partner has been taking 5mg amlopodine a day for high blood pressure. We have been trying to convince for 8 months. We have been seen by a fertility specialist who said that my partners sperm count is fine. I have read that amlopodine can change the shape of the sperms head making it unable to fertilise the egg but this doesn't show on a sperm analysis. Is this true?? Could these tablets be the cause of our problems??