Letter wording: We note that you [have been/were] absent from work with a pregnancy-related illness [since/on [ ]]. Since this illness occurred within four weeks of the week in which your baby is due, we require you (under the Maternity and Parental Leave etc Regulations 1999, regulation 6(b)) to commence your maternity leave with effect from [the day following the first day of the absence within this four-week period].