We suggest you aim for around 8 – 10 weeks before the mum-to-be’s due date. This gives her sufficient time to organise the baby’s lovely new gifts in advance of the big day, putting them away in the nursery, washing and folding away new baby clothes, and buying anything else that is needed. This is also the time she is most likely to be feeling her best. Avoid leaving it too late in the pregnancy when she could feel tired and uncomfortable and perhaps not in the mood for a party or may even have her baby early and miss the whole thing! (It has been known to happen!)
In some cases you may prefer to throw the baby shower after the baby is born. This could be more appropriate especially if the mum-to-be is having complications in her pregnancy, or is in any way superstitious about such things. You could arrange the shower for when the baby is about 6 – 8 weeks old with one advantage being that you know the sex and can buy appropriate gifts.