This document provides an overview of nutrition and fertility. It discusses how adequate nutrition is needed for successful reproduction and how deficiencies can disrupt fertility. It defines terms like fertility, fecundity, infertility, and subfertility. It then discusses factors that can impact fertility like infertility rates, miscarriage causes, subfertility examples, 2020 nutrition objectives, reproductive physiology, the menstrual cycle, hormonal effects, and sources of disrupted fertility including undernutrition, obesity, weight loss, oxidative stress, specific foods/nutrients, and contraceptive use.

1. NDD 10603
LECTURE 2: Preconception
Nutrition
DR. SHARIFAH WAJIHAH WAFA BTE SST WAFA
School of Nutrition and Dietetics
Faculty of Health Sciences
sharifahwajihah@unisza.edu.my
KNOWLEDGE FOR THE BENEFIT OF HUMANITY

2. Introduction
• Adequate health & nutrition status are
needed for successful reproduction
• Inadequate health & nutrition status
may disrupt reproductive capacity

3. Introduction
• Fertility refers to the actual production of
children
• Fecundity addresses the biological capacity
to bear children.
• Infertility -lack of conception after 1 year of
unprotected intercourse.
• Subfertility -reduced level of fertility
characterized by unusually long time to
conception (over 12 months) or repeated
early pregnancy losses.

4. Preconception Overview:
Infertility
• ~15% of couples are infertile
• 44% of couples diagnosed as “infertile”
will eventually conceive without use of
technology
• Healthy couples have a 20% to 25%
chance of conception within a given
menstrual cycle

5. Preconception Overview:
Miscarriage
• Miscarriage: Loss of conceptus in 1st
20 weeks of pregnancy
• Causes of miscarriages:
– Defect in fetus
– Maternal infection
– Structural abnormalities of uterus
– Endocrine or immunological disturbances

6. Preconception Overview:
Subfertility
• Subfertility: Reduced level of fertility
characterized by unusually long time for
conception
• ~18% of couples are subfertile
• Examples:
– Having multiple miscarriages
– Sperm abnormalities
– Infrequent ovulation

7. 2020 Nutrition Objectives for the
Nation Related to Preconception

8. Reproductive Physiology
• Key Terms:
– Puberty—period in which humans become
biologically capable of reproduction
– Ova—eggs females produce & store within
the ovaries
– Menstrual Cycle— ~4 week interval in
which hormones direct buildup of blood &
nutrient stores within uterus; ovum matures
& is released

9. Reproductive Physiology
• Development of female & male reproductive
systems
– Begins during first months after conception &
– Continue to grow & develop through puberty
• Capacity for reproduction
– Establishes during puberty when hormonal
changes stimulate maturation of reproductive
system

10. Reproductive Physiology:
Ova and Women
• Women born with
life-time supply of ~7
million immature ova
• ~400-500 ova will
mature & be
released during
fertile years
• Quality of eggs
decrease with age
due to damage of
cells’ DNA

11. Reproductive Physiology:
Sperm and Men
• Sperm production
begins during
puberty, decreases
somewhat after age
35 with production
continuing to old
age

12. Female Reproductive System

13. Male Reproductive System

14. Hormonal Effects During the
Menstrual Cycle
• Gonadotropin-releasing hormone (GnRH)
– Stimulates pituitary to release FSH and LH
• Follicle-stimulating hormone (FSH)
– Stimulates maturation of ovum & sperm,
production of estrogen
• Luteinizing hormone (LH)
– Stimulates secretion of progesterone and
testosterone

15. Hormonal Effects During the
Menstrual Cycle
• Estrogen
– Stimulates release of GnRH in follicular phase &
follicle growth & maturation of follicle
– Stimulates vascularity & storage of glycogen &
other nutrients within uterus
• Progesterone
– Prepares uterus for fertilized ovum, increases
vascularity of endometrium, & stimulates cell
division of fertilized ova

16. Two Phases of Menstrual Cycle
• Follicular Phase—(first half of menstrual
cycle)
– Follicle growth & maturation
– Main hormones: GnRH, FSH, estrogen, &
progesterone
• Luteal Phase—(last half of menstrual cycle)
– After ovulation
– Formation of corpus luteum
  in estrogen & progesterone stimulate
menstrual flow
– Postaglandins & cramps

18. Male Reproductive System
• Interactions among hypothalamus,
pituitary gland, and testes
• Process is ongoing rather than cyclic
• Androgens — Testosterone
• Sperm are stored in the epididymis &
released in semen

19. Sources of Disruptions in Fertility
• Adverse nutritional exposure
• Contraceptive use
• Severe stress
• Infection
• Tubal damage or other structural
damage
• Chromosomal damage

20. Factors Related to Altered Fertility

21. Nutrition-Related Disruptions in
Fertility
• Undernutrition
• Weight loss
• Obesity
• High exercise levels
• Intake of specific foods & food
components

22. Undernutrition and Fertility
• Undernutrition in women previously
well-nourished
– Associated with a dramatic decline in
fertility that recovers when food intake
does
• Food shortages in countries have been
accompanied by dramatic declines in
birth rates

23. Undernutrition and fertility
•Long-term (chronic) - reduce
fertility by only a small
amount
•The primary effect of chronic
undernutrition -birth of small
and frail infants - high likelihood
of death in the first year of life
•Short-term (acute)- clearly
decreases fertility
•Periods of feast and famine
are associated with major shifts
in fertility.

24. Body Fat and Fertility
• Decreased fertility seen with low or high
body fat due to alterations in hormones
• Estrogen & leptin
– Levels increased with high body fat &
reduced with low body fat
– Both extremes lower fertility
• Infertility lower with BMI <20 or >30

25. Weight Loss and Fertility in Females
– Weight loss >10-15% of usual weight
decreases estrogen, LH, FSH
– Results in amenorrhea, anovulatory cycles,
& short or absent luteal phases
– Treatment with fertility drug Clomid not
effective in underweight women

26. Weight Loss and Fertility in Males
– Studies from World War II showed 50% decrease
in male fertility during starvation
– Sperm viability & motility decrease with wt. 10 to
15% below normal & cease at wt. loss exceeding
25% of normal

27. Oxidative Stress, Antioxidant Status,
and Fertility
• Oxidative stress in men
– Decreases sperm motility
– Reduces ability of sperm to fuse with an
egg
• Oxidative stress in women
– Harm egg and follicular development
– Interfere with corpus luteum function
– Interfere with implantation of the egg

28. Oxidative Stress, Antioxidant Status,
and Fertility
• Antioxidants
– Vitamin E
– Vitamin C
– Beta-carotene
– Selenium
• Found in vegetables and fruits.
• Protect cells of the reproductive system,
including eggs and sperm

29. Oxidative Stress, Antioxidant Status,
and Fertility
• Supplemental intakes of vitamin E and
selenium improve sperm quality in
infertile men.
• Regular intake of vitamin C, vitamin E,
and beta-carotene supplements have
been related to increased sperm
number and motility

30. Oxidative Stress, Antioxidant Status,
and Fertility
• Zinc status and Fertility in Men
o Plays important roles
• In the reduction of oxidative stress
• In sperm maturation
• In testosterone synthesis
o Lower zinc status in men related to:-
• poorer sperm quality,
• sperm concentrations, and
• to abnormal sperm shapes.

31. Plant Foods and Fertility
• Low-fat, high fiber linked to irregular
menstrual cycles
• Isoflavones (from soy) decrease levels
of estradiol, progesterone, LH
– Also related to reduced sperm count in
men
– one–day increase in menstrual cycle length
in women

32. Folate Status and Fertility
• Intake by women of multivitamins with
folate associated with decline in
ovulatory infertility
• Intake by men of multivitamins with
folate associated with improved sperm
counts, motility, decreased abnormal
forms of sperm

33. Folate Status Prior to Conception
and NTDs
• inadequate folate very early in
pregnancy can cause neural tube
defects (NTDs).
• develop within 21 days after conception
—or before many women even know
they are pregnant, and well before
prenatal care begins.

34. Iron Status and Fertility
• Rate of infertility lower in women who
use iron supplements or iron from plant
foods
• low iron stores and frank deficiency are
common among women of childbearing
age.
• Interferes with ovulation and may result
in pre-term delivery.

35. Caffeine and Fertility
• Study results are mixed on effects of caffeine
– Some studies have shown increased time to
conception, others have failed to find effects
• If individuals choose to cut back on caffeinated
beverages, it is their choice

36. Alcohol and Fertility
• Alcohol may decrease estrogen &
testosterone levels or disrupt menstrual
cycles
• Studies on weekly drinks consumed
show:
– 1-5 drinks  39%  in conception
– >10 drinks  66%  in conception

37. Heavy-Metal Exposure and Fertility
• High lead levels – decreased sperm
production, abnormal motility, shape
• Build-up of cadmium, molybdenum,
manganese, boron, and other metals
also affect male fertility

38. Exercise and Fertility
• Adverse effects of intense physical activity
– Delayed age at puberty
– Lack of menstrual cycles
– Appear to result from hormonal and metabolic
changes
– Related to caloric deficits
– Reduced levels of estrogen
– Low levels of body fat
– Decreased bone density

39. Nutrition During the Periconceptual
Period
• Very-early-pregnancy nutrition exposures
• Folate status prior to conception
– Neural tube defects
• Iron status prior to conception
– Iron deficiency is most common deficiency
worldwide
• Recommended dietary intakes for
preconceptional women

40. Nutritional Disruptions

41. Hormonal Contraception
• Fertility-control products for females
include:-
– Pills,
– contraceptive implants,
– patches, and
– injections.

42. Hormonal Contraception

43. Hormonal Contraception

44. Nutritional Side Effects of Hormonal
Contraception
• Oral Contraceptives
– Increased blood levels of HDL cholesterol (the
“good” cholesterol)
– Increased blood levels of triglycerides and LDL
cholesterol
– Increased risk of venous thromboembolism (blood
clots), cervical cancer, and cardiovascular disease
– Decreased blood levels of vitamins B12 and B6
– Increased blood levels of copper

45. Nutrition-related side effects
of contraceptives
• Contraceptive Injections (Depo-Provera)
– Weight gain (averages 5.5 kg) during one to three
years)
– Increased blood levels of LDL cholesterol and
insulin
– Decreased blood levels of HDL cholesterol
– Decreased bone density
• Contraceptive Implants (Norplant)
– Weight gain (Average weight 4.1 kg) gain after 1
year after implant)

46. • Contraceptive Patches (placed on the
skin for 3 weeks and then taken off for a
week.)
– increase blood levels of cholesterol and
triglycerides
– increase the risk of blood-clot formation
– increases in HDL-cholesterol levels
Nutrition-related side effects
of contraceptives

47. Premenstrual Syndrome
• Characterized by life-disrupting
physiological & psychological changes
that begin in the luteal phase & end with
menses
• Symptoms occur in 15-25% of
menstruating women

48. Common Symptoms of PMS

49. Premenstrual Dysphoric Disorder
• PDD-severe form of PMS
• Characterized by marked mood swings,
depressed mood, irritability, & anxiety
• Physical symptoms:
– Breast tenderness
– Headache
– Joint & muscle pain

50. Possible Cause of PMS
• Cause is not yet clear
• Thought to be related to abnormal
serotonin activity following ovulation

51. PMS Treatment
• Antidepressants containing serotonin uptake
inhibitors reduce PMS
• Calcium, B6, chasteberry supplements
– Calcium—1200 mg/day
– Vitamin B6—50 to 100 mg/day
– Chasteberry – 20 mg/day
• Reduced caffeine intake, supplementation of
vit D and magnesium - limited results

52. Weight Status and Fertility
• Obesity and
underweight
increase likelihood
of reproductive
health problems

53. Obesity, Body Fat Distribution, and
Fertility
• Central body fat & fertility
– Central obesity interferes with reproduction
in women and men
• Weight loss & fertility
– Should be treatment of first choice for
obese people
– Fertility problems can be reduced or
eliminated by weight loss

54. Obesity, Body Fat Distribution, and
Fertility
• Weight Reduction Methods
– Focus on lifestyle changes
– Decrease calorie intake
– Increase physical activity levels
– Weight loss surgery if efforts fail – bariatric
surgery

55. Metabolic Syndrome
• Cluster of abnormal metabolic & health
indicators
• Diagnosed if 3 of 5 conditions exist:
1. Waist circumference:
>40” in men & >35” in women
2. Blood triglyceride ≥150 mg/dL
3. HDL-cholesterol:
<40 mg/dL in men & <50 mg/dL in women
4. Blood pressure >130/85 mm Hg
5. Fasting blood glucose ≥100 mg/dL

56. Metabolic Syndrome
• Consequences
– Increases risk of CVD & type 2 diabetes
• Therapy
– Dietary modification
– Weight reduction
– Exercise

57. Pregnancy after Bariatric Surgery
• Fertility may return after surgery
• Bariatric surgery increases risk for the
following deficiencies
– Calcium, iron, copper, zinc, thiamin, B6, B12, and
D
• Pregnancy is not recommended during first
year after surgery
– Monitor nutritional status because of poor nutrient
status during post-surgery weight loss

58. Hypothalamic Amenorrhea
• Hypothalamic Amenorrhea: Cessation of
menstruation related to changes in
hypothalamic signals that maintain ovulation
(“functional hypothalamic amenorrhea,”
“weight-related amenorrhea”)
• Caused by deficits in energy & nutrients

59. Eating Disorders and Fertility
• anorexia nervosa and bulimia nervosa are
linked to hypothalamic amenorrhea in some
women
– More likely to miscarry, have preterm delivery,
have low birthweight infants
• Menses typically resumes with weight gain
• Care involves evidence based practice
– interdisciplinary group of experienced health
professionals

60. The Female Athletic Triad and
Fertility
• Triad consists of:
– Amenorrhea
– Disordered eating
– Osteoporosis
• Triggered when energy intake is ~30% less
than requirement
• Results in decrease in LH, FSH & lack of
estrogen
• Low hormone levels lead to reduction in
bone density

61. Management of the Female Athletic
Triad
• Correction of negative energy balance
• Correction of eating disorders
• Vitamin D & calcium supplements to
facilitate bone development

62. Diabetes
• Diabetes Mellitus—intolerance to
carbohydrate with fasting glucose ≥126
mg/dL
• Types of diabetes
– Type 1—results from destruction of insulin-
producing cells (10% of cases)
– Type 2—body unable to use insulin normally, to
produce enough insulin or both (90%)
– Gestational—onset during pregnancy (3-7%)

63. Diabetes Mellitus Prior to Pregnancy
• High blood glucose levels during the
first 2 months of pregnancy are
teratogenic
• Associated with a 2-3 fold increase in
congenital abnormalities in newborn
• Malformations of pelvis, CNS, & heart
seen in newborns, higher rates of
miscarriage

64. Management of Type 1 Diabetes
• The main goals of management of type 1
diabetes are:
– Blood glucose control
– Resolution of coexisting health problems
– Health maintenance
• Diets are controlled in carbohydrate content
• Insulin use
• Physical activity

65. Management of Type 1 Diabetes
• Diet management may be handled in
the following ways:
– Carbohydrate control
• Carbohydrates raise insulin needs more than
proteins and fats
• Dietary advice must be tailored for
every person

66. Management of Type 1 Diabetes
• Diet choices are encouraged:
– Replace simple sugars with reasonable amounts
of artificial sweeteners
– Choose foods low in glycemic index and high in
fiber (especially soluble fiber)
– Encourage brightly colored fruits and vegetables
– Low fat meat and dairy products, fish, dried beans
and nuts & seeds

67. Management of Type 2 Diabetes
• Type 2 diabetes may be managed with:
– Diet and exercise and oral medication to increase
insulin production and insulin sensitivity
• Preferred management program
– Individualized diet and exercise recommendations
– Weight loss

68. Prevention of Gestational Diabetes
(GDM)
• Considered to be a form of type 2 diabetes
• Pre-pregnancy weight loss, increased fiber
intake and exercise reduce risk of GDM
• Adherence to healthful diet high in fruits and
vegetables

69. Polycystic Ovary Syndrome
• 5-10% of women of childbearing age
• The leading cause of female infertility
• Many with PCOS are obese or have
high levels of intra-abdominal fat
• Cause is uncertain
– Insulin resistance a possible factor
– Appears to have strong genetic component

70. Phenylketonuria
• PKU (phenylketonuria)
– Elevated blood phenylalanine due to lack
of phenylalanine hydroxylase
– Preventable cause of intellectual disability
• Nutrition management for women with
PKU
– Low-phenylalanine diet for life

71. Celiac Disease
• Celiac disease
– Autoimmune disease characterized by
chronic inflammation of small intestine
• Inherited sensitivity to gluten in wheat, rye,
barley, which causes malabsorption & flattening
of intestinal lining
• Linked to infertility in some women &
men