Nutrition Throughout the Lifespan (Pregnancy)

• Fertility is the actual production of children
• Fecundity is the biological capacity to bear children
• Subfertility is the unusual long time to conceive (>12 mos) or repeated pregnancy losses
• Infertility is the absence of production of children or biological inability to reproduce
• Pregnancy (known as 'gestation') is the period from conception to delivery that lasts for 266 to 270 days or 38 weeks
• If as duration, it lasts for 280 days or 40 weeks as it is measured from the data of the last Menstrual Period (LMP)
• Maternal Phases:

  • Anabolic Phase
  • Catabolic Phase
• Anabolic Phase happens during 0 to 20 weeks
• Catabolic Phase happens at >20 weeks
• Energy Source for Pregnancy are fat stores for mother, and glucose for baby
• Physiological Stages of Pregnancy

  1. Implantation
  2. Organogenesis
  3. Fetal Growth
• Implantation is the first two weeks
• Organogenesis is completed 60 days after conception
• Fetal Growth continues on the remaining 7 months
• 6 Key Hormones in Pregnancy

  1. Human Chorionic Gonadotropin
  2. Progesterone
  3. Oestrogen
  4. Prolactin
  5. Relaxin
  6. Oxytocin
• Human Chorionic Gonadotropin (hCG) is produced by the placenta after implantation.
• Human Chorionic Gonadotropin (hCG) supports the function of the corpus luteum, a temporary structure in the ovaries essential in early pregnancy.
• Human Chorionic Gonadotropin (hCG) is also the hormone detected by pregnancy tests.
• Progesterone helps establish the placenta.
• Progesterone stimulates growth of blood vessels that supply the womb and inhibits contraction of the uterus so it grows as the baby does.
• Progesterone also strenghtens pelvic wall muscles for labour.
• Oestrogen helps the uterus grow, maintains its lining, and helps foetal organs develop.
• Oestrogen activates and regulates production of other hormones.
• Oestrogen with progesterone, stimulates breast growth and milk duct development.
• Prolactin is the main hormone needed to produce breast milk.
• Prolactin contributes to enlargement of the mammary glands and prepares them for milk production.
• Progesterone inhibits lactation during pregnancy.
• Relaxin inhibits uterus contraction to prevent premature birth.
• Relaxin relaxes blood vessels, increasing blood flow to the placenta and kidneys.
• Relaxin relaxes the joints of the pelvis and softens and lengthens the cervix during birth.
• Oxytocin levels rise at the start of labour, stimulating contractions of uterine muscle.
• Oxytocin triggers production of prostaglandins, which increase contractions further.
• If labour doesn't start naturally, oxytocin can be used to induce it.
• Human Chorionic Gonadotropin is the hormone detected by pregnancy tests; supports early pregnancy.
• Progesterone helps establish placenta; supports pregnancy by inhibiting uterus contraction.
• Estrogen helps uterus grow and fetal organs develop.
• Prolactin is for breast enlargement and milk production.
• Relaxin relaxes uterus lining; inhibits contraction.
• Oxytocin stimulates contraction; for labor.
• Other Hormones Involved:

  1. Human Placental Lactogen (HPL)
  2. Human Chorionic Thyrotropin (HCT)
  3. Human Growth Hormone (HGH)
  4. Thyroid-Stimulating Hormone (TSH)