MHMW

Third trimester

41 weeks pregnant: what is happening this week

Week 41 of 42worked example

3 to 4 kg

This week runs
Thu, Oct 8, 2026 to Wed, Oct 14, 2026
Days to the estimated due date
0
Term window (37-42 weeks)
Thu, Sep 17, 2026 to Thu, Oct 22, 2026

No size figure is shown for this week, because none is published. The NHS gives a weight at week 41 and no length, so this page carries the weight and leaves the length out.

No length this week - the NHS stops publishing one at 41 and gives a weight instead: around 3 to 4 kg on average. That is the only weight figure in the entire week-by-week guide, which is why every other page here carries a length and no weight. A range rather than a number, and a wide one, which is the appropriate way to report it. The rapid growth phase is over. Skin may look red and be peeling, because the vernix that protected it has largely gone. Everything needed for life outside is finished. This is the week induction is discussed properly. The NHS offers it from around 41 weeks, and the conversation covers what it involves, what the alternatives are, and what monitoring looks like if you wait. It is a decision with options in it rather than a procedure that happens to you, and going into that appointment having read the NHS page on induction makes it a conversation between informed people. Being past the estimate is common, is not a failure of anything, and is precisely what a five-week term window predicts.

Put your own dates on week 41

Week 1 began
Thu, Jan 1, 2026
Week 41 begins
Thu, Oct 8, 2026
Week 41 ends
Wed, Oct 14, 2026
Estimated due date
Thu, Oct 8, 2026

Dates run on ACOG's 280-day convention, the same arithmetic as the due date calculator. Share this week with your dates: /pregnancy/week-41?s=d:2026-10-08

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What the NHS describes this week

  • The NHS gives an average weight of around 3 to 4 kg at this stage, and no length.
  • The rapid growth phase is complete and every system is ready for life outside.
  • The skin may look red and peel as the vernix that protected it is lost.

What happens around now

Induction of labour is discussed from around 41 weeks. The NHS describes it as an offer with alternatives, including monitoring while waiting, rather than an automatic step.

  • 41-week antenatal appointment - position, and a discussion of the options after 41 weeks including induction (NHS)

Where week 41 comes from

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