Final answer:
Breastfeeding can help space pregnancy due to the elevated levels of prolactin during frequent nursing, which suppress ovulation and act as a natural contraceptive.
Step-by-step explanation:
How does breastfeeding help to space pregnancy? Breastfeeding has an amenorrhaeic effect, meaning it can cause a temporary absence of menses (menstruation). This happens due to the high levels of the hormone prolactin, which is necessary for milk production and is elevated during frequent breastfeeding sessions. This hormonal change can suppress ovulation, acting as a natural form of contraception. In addition, other hormones such as oxytocin, growth hormone, cortisol, parathyroid hormone, and insulin contribute to the lactation process and play a role in this effect. Consequently, exclusive and frequent breastfeeding helps in spacing out pregnancies by extending the period of amenorrhea.