Post-pregnancy and childbirth, it takes some time to recover and to resume some normalcy, especially in your cycle. Due to the demand that pregnancy and breastfeeding puts on the body, most health agencies (including the World Health Organization) recommend not becoming pregnant again for at least 12 months after giving birth. If you’re not breastfeeding, you could ovulate as early as the first few weeks after giving birth, but what if you are pumping or breastfeeding? Let’s look at what happens when we produce breast milk in relation to ovulation and when you should consider using contraception.
What hormones are affected when breastfeeding or pumping?
Prolactin is the hormone that tells breast tissue to grow and produce milk, so when your breastfeeding or pumping you’ll have a great amount of this hormone around. When prolactin levels are high, it sends a feedback message to your hypothalamus (a little gland that sits under the brain) to stop gonadotropin-releasing hormone (GnRH). By stopping this signal, the ovaries are prevented from getting the hormones that cause egg development and ovulation.
Prolactin spikes in your body during nipple stimulation (pumping) and suckling. Prolactin also follows a circadian rhythm—a sleep-wake cycle—naturally peaking around the hours of 1 a.m. to 5 a.m., at its lowest during the daytime.
When you start weaning off breastfeeding or pumping or when there are longer periods between feedings, prolactin levels will go down, which means GnRH comes back online and you can start ovulating again within two to four weeks.
Am I ovulating if my period returns?
Having a menstrual flow doesn’t mean that you're ovulating—this holds true whether you’re breastfeeding or not. You can also ovulate just before the return of your first menstruation postpartum, so it’s possible to become pregnant even before you’ve had your first postpartum period. Having a period is not a good indicator of if you are ovulating.
Can I breastfeed or pump as a method of birth control?
Producing breast milk is an unreliable method of birth control and is not recommended if you’re trying to prevent pregnancy. Although the prolactin hormone, in high enough concentrations, can prevent ovulation, there is no guarantee this will happen. It’s highly recommended to use a barrier form of contraception while breastfeeding.
For additional context, in one study of 60 breastfeeding mothers, there was a higher risk of ovulation with infrequent feeds or pumping sessions and with shorter duration pumping or feeding. In this study, it was reported that for women without a menstrual period during the first six months postpartum, the risk of ovulating was about five to 10 percent with partial breastfeeding, and one to five percent when exclusively breastfeeding. However, if menstruation resumed within those first six months, or if breastfeeding continued beyond six months, the risk of ovulation increased, requiring the use of contraception.
Why is contraception important during breastfeeding?
Pregnancy and breastfeeding both put high demands on the body, especially when it comes to energy and nutrients. When pregnancies are not spaced out by at least 12 months, there are increased health risks including preterm birth and low birth weight babies.
Do ovulation tests work when you’re breastfeeding?
Ovulation test strips measure the amount of luteinizing hormone (LH) in your urine. When LH peaks high enough, it causes the test line on the strip to show up and become dark. Ovulation typically occurs about 24 to 36 hours after this LH surge. However, since prolactin suppresses LH, there’s a good chance you won’t see that LH surge on your test strips, especially if you haven’t had your period come back yet. In short, ovulation tests are not reliable when you’re nursing, if you’re hoping to use them to predict ovulation to avoid pregnancy. But they can be used to understand the fluctuations in your cycle after childbirth. By testing over time, you may be able to have a better idea of when you are ovulating again.