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"How does breastfeeding affect period length?"


I'm a new mother with an eight month old daughter who I'm breastfeeding, and I'm starting to wonder if this could be affecting my periods. My periods seem more prolonged and delayed than they ever were before. Can nusing have that effect, or is it just a coincidence?


Yes. Nursing causes numerous changes including alterations of the menstrual cycle. After giving birth, it is common for many women to not have a period for several months, especially if they are breastfeeding.

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Most women will have resumed ovulation by 6 months, but there is a sizable minority who will still not have periods at that point. It is important to note that a woman can become pregnant, even while breastfeeding. A urine pregnancy test can accurately answer that question if you are wondering if you might be pregnant again. There are several hormones that are released during breastfeeding, including oxytocin and prolactin, both of which can affect the female reproductive cycle. As the female body returns to the pre-pregnant state, there can be hormonal shifts and variations that can affect a woman in many ways, including her ovarian cycle. Over time these variations will resolve, and your cycles should become more regular, even though they might not return to the same state as they had been previously until some time after giving birth. Even though all of these changes can be completely expected and common with a pregnancy and nursing, it is important to discuss these changes with your obstetrician or midwife at your regular visits (or sooner) to determine if there are any unique factors in your situation.

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