When is colostrum secreted during pregnancy?

Colostrum is the first form of milk produced by the mammary glands and is rich in antibodies and nutrients, making it vital for newborns. It typically begins to be secreted in the third trimester of pregnancy, particularly around the 28th week onward. This timing aligns with the body's preparations for breastfeeding, ensuring that colostrum is available for the newborn immediately after birth.

While some women may experience leakage of colostrum earlier, the significant production and secretory changes occur in the later stages of pregnancy. This is why saying that colostrum is secreted in the third trimester is accurate. The other options do not reflect the typical physiological process of milk production during pregnancy. At conception, there is no milk production; colostrum does not continue throughout the entire pregnancy; and it is not actively secreted during the middle phase of pregnancy. Therefore, the correct understanding of colostrum secretion is that it notably begins in the latter part of pregnancy, specifically during the third trimester.