Jackson R L
Department of Child Health, University of Missouri, Columbia.
Clin Pediatr (Phila). 1988 Aug;27(8):373-7. doi: 10.1177/000992288802700804.
Until the 2nd and 3rd decades of this century, breastfeeding was essential for infant survival. In that period, spacing of children was generally about 2 years. Later, improved modified cow's milk preparations became commercially available and were well tolerated by most infants. As a result, near cessation of ecological breastfeeding occurred toward the middle of the century. The decline in ecological breastfeeding was associated with early postpartum ovulation and shortened child-spacing of about 1 year. The endocrinology of breastfeeding is now known in considerable detail. Prolactin is secreted promptly in response to nipple stimulation and is a reliable marker of the endocrine alterations occurring postpartum. Success of lactation in suppression of ovulation was found to occur when infants sucked frequently and when only small amounts of selected foods were introduced gradually after the infants were about 6 months of age.
直到本世纪二三十年代，母乳喂养对婴儿存活至关重要。在那个时期，孩子的间隔时间通常约为两年。后来，改良的牛奶制品商业化供应，大多数婴儿对其耐受性良好。结果，到本世纪中叶，生理性母乳喂养几乎停止。生理性母乳喂养的减少与产后早期排卵及孩子间隔时间缩短至约一年有关。现在人们对母乳喂养的内分泌学已有相当详细的了解。催乳素会因乳头刺激而迅速分泌，是产后发生的内分泌变化的可靠指标。当婴儿频繁吸吮且在婴儿约6个月大后逐渐少量引入特定食物时，发现哺乳成功抑制了排卵。
