You can try couple fertility test packages offered by many hospitals.
For guys, it is usually Sperm Analysis and maybe a full hormone count.
For women, it can be full hormone count, ultrasound, HSG (to rule out blocked tubes).
I did mine at different junctures and hence it cost more. Best is if you do it at a go with some packages available at raffles, TMC, Mount E and so on. For cheaper rates, you can even consider JB during a weekend