Gases that contribute to the greenhouse effect include: 1  Water vapor. 2  Carbon dioxide (CO 2). 3  Methane. 4  Nitrous oxide. 5  Chlorofluorocarbons (CFCs).
You can start maternity leave any time from 11 weeks before the beginning of the week your baby's due. You can bring the date forward if you need to take time off work for pregnancy-related reasons within four weeks of the expected birth date. Your employer may make you start your leave from then.
The shortest maternity leave you can take is 2 weeks. This goes up to 4 weeks if you work in a factory. If you want to take more than a year off. You donât have a right to more than a year of maternity leave, but your employer might agree to let you take extra time away from work.