Hi,me and my partner are trying to have a baby,...

Does your husband medical condition effects his ability of conceiving ?
yes , your husband medical condition such DM will effects sexual ability and sperm quality , as well as DM and HTN medications will effects sperm quality 
Medical options to increase sperm quality
1. consult a fertility doctor to do the needed medical examinations and determine the treatment options ( if needed )
2. usually doctors in this case will prescribe a suppliments ( such as cycle fert ) to increase sperm quality and motility such as :
- selenium 
- vitmain E 
- zinc
- copper 
- vitmain D 
3. other drugs options are :
- DHEA ( in case of low testerone levels )
- Clomiphene Citrate 
- Human Chorionic Gonadotropin (HCG)
4. you have to use this suppliments for 100 days then redo sperm analysis test 
General advices to increase your chance of getting pregnant ?
1. make sure to do the sexual intercourse during the ovulation time to increase the chance of getting pregnant 
2. performing sexual intercourse many timeswont effect the quality of male semen , but in the same time ,  performing it in excessive way such as ( 3 times daily ) won't increase the chances of getting pregnant , so just try to perform sexual intercourse in mild range such as once daily and it's enough to get you pregnant 
3. lie down after sexual intercourse for about half an hour , and don't wash your private parts directly after that 
4. take care of your and your partner life style quality , eat healthier food , sleep well , avoid stress and anxiety , do exercise regulary
How to know ovulation days and the safe days in period :
1. ovulation time or the time ovum exist are the first 4 days of the last 16 days of the period , for example ;if your period is 28 days , and  if your first day of period was 1st/9 , your ovulation time is 12th-16th /9 
2. the ovum last 48 hours in the uterus and can get fertilized any time during this period of time 
3. male semen lasts up to 5 days in female uterus and will be able to fertilize during this period of time , but the earlier the better 
Medication to help you get pregnant ?
1. multivitamins and fertility supplements 
2. ovulation activation injections 
3. folic acid 
- first , consult your doctor before taking any of those medications