This is describing the pathophysiology behind lactational amenorrhea. However, lactation alone does not cause this; it requires strict, near-exclusive breastfeeding to achieve.
Amboss writes it "occurs among women who breastfeed exclusively within the first 6 months postpartum and lasts for ~ 10 months. Mediated by the suckling stimulus, which stimulates prolactin release, inhibits gonadotropin-releasing hormone (GnRH) release, and inhibits the preovulatory lutenizing hormone (LH) surge."
On the page regarding this, they also write "lactational amenorrhea which is highly effective in the first 6 months if an infant is exclusively, or almost exclusively, breastfed."
Source: AMBOSS - https://next.amboss.com/us/search?q=lactational+amenorrhea





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