All women experience a time of postpartum bleeding following birth which is not considered a menstrual period. If bottle feeding, most mothers will have their first real period not long after this. Breastfeeding, however, suppresses menstruation at least for a while. For some mothers, there may be an absence of menstruation for weeks, months, and even years while still breastfeeding. Some mothers report needing to completely wean before they see their first period. Others begin menstruating as soon their babies begin taking supplemental foods or sleeping through the night. Once menstruation returns it may continue to be irregular during lactation. It’s not uncommon to have a shorter or longer than normal period while breastfeeding. It’s also not abnormal to skip a period or see the first period return and then find that months pass before the next one (1a).
When the first period returns depends upon several factors: how frequently the baby is nursing, how often the baby is supplemented with bottles, whether or not the baby takes a pacifier, how long the baby is sleeping at night, whether or not solids have been introduced, and the mother’s own individual body chemistry and the way it responds to hormonal influences associated with breastfeeding. Any time the stimulation to the breast is decreased, especially at night, menstruation is likely to return soon after (1b).
When menstruation does return, you should consider yourself fertile and take precautions against pregnancy if desired. Some women consider their first period as their “warning period” that they are now capable of becoming pregnant. However, it is possible to become pregnant before the first period returns, although quite rare (1c).
The return of menstruation does not mean the end of breastfeeding. The milk does not sour or “go bad” when you are having a period. The milk is no less nutritious when you are menstruating than when you are not. Some women do notice a temporary drop in milk supply in the days just prior to a period and for a few days into one. This is due to hormonal fluctuations. Once the period begins and hormone levels begin to return to normal, the milk supply will boost back up again. Most babies can compensate well for this temporary drop in supply with more frequent nursing (1d).
Nipple tenderness occurs for some women during ovulation, during the days before a period, or at both times. Some mothers report feeling antsy while nursing at these times, too. As with the drop in supply this is also hormonally influenced and therefore temporary (1e).
Some babies may detect a slight change in the taste of the milk just before a period, again, due to hormonal changes. These same babies may nurse less often or less enthusiastically during this time as a result. Almost anything is considered normal when it comes to your periods while breastfeeding (1f).