Most studies indicate that progesterone is not harmful to milk production or the duration of breastfeeding. The main hormones of lactation are estrogen, progesterone, oxytocin and prolactin. Each one plays a different and very important role in the feeding process. An imbalance in any of these natural hormones can alter the breastfeeding experience, so it's important to understand the hormonal fluctuations that the body goes through during pregnancy, childbirth and delivery, not to mention the postpartum period and weaning.
Once labor begins, our hormonal balance experiences a major disorder. There are many hormones that act during labor, but the main ones affecting breastfeeding are oxytocin, progesterone and prolactin. The factors that initiate labor are multifaceted and complex, but one of the main contributing factors, in part, is the increase in the level of the hormone oxytocin. If you've given birth, you probably know what contractions feel like.
The culprit behind these painful but significant labor pains is oxytocin. During labor, oxytocin increases, causing the uterus to contract and eventually dilates the cervix to prepare it for delivery. Skin-to-skin contact with a newborn doesn't just cause an increase in oxytocin levels. It also promotes augmentation of prolactin levels.
When progesterone levels drop and prolactin peaks, the body gets the message that it's time to produce breast milk. From this period onward, and throughout the breastfeeding period, the most important factor determining milk production is the amount of milk that is regularly emptied from the breast. However, although the volume of milk produced no longer depends solely on hormonal control, hormones continue to play an important role in maintaining oxytocin lactation. As mentioned before, oxytocin is released during skin-to-skin contact between parents and children.
Not only does this promote an intimate bond, but it can also help maintain parents' mental health. during the postpartum period. In fact, breastfeeding has been shown to prevent mental health symptoms during this period and high oxytocin levels are suspected to play an important role. Once a child stops needing breast milk, the body stops producing it.
As milk production decreases and eventually stops, prolactin and oxytocin levels decrease. During breastfeeding, these hormones promote feelings of satisfaction, peace and privacy. I think large studies show us, in general, that contraceptives that only contain progesterone MAY be a good option. They are unlikely to have a harmful effect on breastfeeding or on infant outcomes.
This is the information your obstetrician gynecologist will be looking for. Milk production is intricately regulated by endocrine and autocrine control mechanisms, and estrogen and progesterone play a fundamental role in this process. A transgender woman was taking 4 mg of sublingual estradiol twice a day, 100 mg of spironolactone twice a day, and 200 mg of progesterone at bedtime as gender-affirming therapy. Estrogen and progesterone are hormones that maintain pregnancy and prevent premature birth or miscarriage.
In addition to endogenously produced hormones, external substances capable of interfering with normal hormonal actions, such as phytoestrogens, mycoestrogens, synthetic estrogens and hormonal contraceptives, can influence milk production. Although the data are unprecedented and, at the moment, are anecdotal, I think they are sufficient to question methods based solely on progesterone.
