In an effort to beat the clock, showers are usually given four to six weeks before the baby's due date. Parents who receive gifts in advance of the birth have the advantage of knowing what additional items they'll need to buy or borrow. However, showers can also wait until a few weeks after the birth. In fact, some expectant couples prefer to defer receiving gifts until after the baby's arrival.
Store-bought fill-ins come in a wide variety of designs and are widely available, as are invitations that can be designed online or on your computer. However creative your invitation, don't forget the essentials: the mother's (or parents') names(s), the shower's date, time and location, and a request to RSVP. Gift information is never listed on the invitation itself, but it's fine to mention "The nursery is blue and green," or, "Jenna's expecting a girl." The host should be prepared to give gift suggestions, and nowadays it's acceptable to include baby registry information on a separate enclosure.
Invitations are sent out three weeks before the shower.