I had a few people ask questions about the return of your period during the postpartum phase - particularly while breastfeeding!
I have seen great variation in the amount of time it takes for a woman’s period to return and regulate. To start, prolactin is the main hormone responsible for milk production. And when elevated (hence, for breastfeeding) it works to prevent ovulation.
So, typically, if you aren’t breastfeeding, your period (and potential ovulation) will return much quicker than someone who is breastfeeding. Once you’ve had a period, you should assume that you are fertile, and should use protection (if you prefer not to become pregnant again). In fact, you may be ovulating prior to that first postpartum period - so be aware of this!
During breastfeeding, return of that first period and further regulation of the cycle can depend on a number of factors:
How often is the baby nursing?
Are you pumping?
Other supplemental sources – Is the baby being bottle-fed at all? Has the baby already been introduced to solids?
How long is the baby sleeping at night? Are you going an entire night without feeding or pumping?
Basically, the more stimulation the breasts receive, the more prolactin = less likely to menstruate. The less stimulation the breasts receive (ie. going an entire night without feeding or pumping) = more likely to menstruate.
And interestingly enough, the Lactational Amenorrhea Method strategically utilizes breastfeeding as a birth control method – and one of the biggest factors is night nursing. Night nursing is considered ‘protective’ against pregnancy, and is highly correlated with anovulation (lack of ovulation) and amenorrhea (lack of period). (1)
And to complicate things further, prolactin can be increased by a number of factors, including the following (2):
Stress (vague, I know)
Hypoglycaemia (low blood sugars)
Exercise (say what?)
Pituitary tumor (prolactinoma)
Medications: dopamine antagonists, and some antidepressants, psychotropics and antihypertensives (blood pressure medications)
(1) Rivlin, K. Westhoff, C. Family Planning, Comprehensive Gynecology; 13, p. 237-257. E1.
(2) Bronstein, M. Disorders of Prolactin Secretion and Prolactinomas, Endocrinology: Adult and Pediatric; Chapter 7, p. 104-128. E6.