If you are able to work, then you will be expected to look for work when pregnant. If your doctor puts you on sick leave, then you can still get RAV assistance, just as if you were working or looking for work.
As far as I know, the maternity leave conditions will be standard, and you certainly will be expected to look for work during the pregnancy that you can begin after the maternity leave, if not before.
Rumours are just rumours... best to not worry and to take the opportunity to think about what you want to do 'in an ideal world'.
It's a good idea to think about 'downsizing' anyway financially before the baby comes...if you can...
The eligibility for maternity leave is not tied to one employer...you can work for one for a few months, then another one...as long as you have been paying in to the insurance system through your employment and satisfied the requirements.
A summary is here:
https://www.ch.ch/en/maternity-leave/
It says quite clearly that you need to have worked 9 months prior to the maternity and 5 months of the pregnancy to qualify... and still 'employed' at the time of the birth.
It also says quite clearly that you cannot be dismissed whilst pregnant...so there may be a situation where even if your employer 'wound up' the company during your pregnancy, they would have to pay for your employment for the duration of the pregnancy, plus the duration of the maternity leave, and could only give notice the first day that you are required to be back to work after this period.
I have seen this happen. The employer was in the process of terminating the employment due to poor performance, the employee was aware of this, and the day that the employer served notice of termination, the employee said "oh, but I'm pregnant" - they were then legally entitled to continue their employment right through the rest of the pregnancy and maternity leave and the 3 months notice period of their contract, before finally completing the termination of the employment... it was the employer's choice whether to require them to attend work or ask them not to turn up for work...and the employee's right to get a medical certificate if they were unwell and unable to work... it was a very long process - 8 months pregnancy, 4 months maternity leave, 3 months notice period... and a lot of legal advice on both sides and paperwork to make it all legally watertight...