Most major cruise lines, including Royal Caribbean, Carnival, Disney Cruise Line, and Norwegian, have a strict policy that prohibits guests from sailing if they have entered or will enter their 24th week of pregnancy (approx. 6 months) at any point during the cruise. This means you must typically complete your voyage before reaching the 24-week mark. This policy is primarily for safety, as cruise ships are not equipped with neonatal intensive care units or obstetricians to handle premature births or complex pregnancy complications while at sea. Expectant mothers are usually required to provide a physician's letter stating their due date and confirming that both mother and baby are in good health. Because the availability of specialized medical facilities can be problematic in foreign ports, cruise lines prioritize the safety of the mother and child by restricting travel during the third trimester when the risk of spontaneous labor or complications increases.