IVF pre-op consultation

Holly
Hi ladies, please can someone give me some advice about what to expect at the pre-op consultation? And also how likely it will take after this to start the <a href="https://glowing.com/glow-fertility-program">ivf</a> cycle? 
My husband and I have been ttc for 4 years with no luck whatsoever. After a very long road, finally we have a a pre-op appointment on Tuesday - I'm sooo excited as really feel the whole process may finally be starting. However, I have thought this in the past and then we end up with more loop holes to jump through. Can anyone tell me what happens at this appointment and how long it is likely to be before the <a href="https://glowing.com/glow-fertility-program">ivf</a> actually starts? Thank you lovely ladies and good luck in your journeys xx