Understanding Fertility Hormones: Key Signs, Imbalances & Tests
Oestrogen. Testosterone. Progesterone. These are just some of the hormones you hear throughout your life that affect systems in your, how you feel and your mood.
During menopause, these fertility hormones begin to become unbalanced, forcing an array of changes in the body and your quality of life. We have other articles discussing how your body changes throughout menopause, but this article will cover what these hormones are and what they do during menopause.
Jump there now:
- What Are Hormones?
- The Main Fertility Hormones
- The Menstrual Cycle and Hormones
- Tracking Your Fertility
- Factors Affecting Fertility Hormones
Hormones are chemical messengers produced by the endocrine system, which includes glands like the thyroid, pancreas, ovaries and pituitary glands. These glands release hormones into the bloodstream, traveling to various organs to regulate many functions, including growth, metabolism and reproduction.
For women trying to conceive, hormones are especially important. They control the menstrual cycle, the maturation of eggs and the readiness of the uterus to support a pregnancy. When hormonal levels are not balanced, it can lead to issues with fertility.
Which hormone is responsible for fertility? Several hormones work together to regulate a woman’s reproductive system. Here are the key players:
Follicle-Stimulating Hormone (FSH)
What It Does:
FSH is a hormone produced by the brain’s pituitary gland and is important in the early stages of the menstrual cycle. It stimulates the growth of ovarian follicles, which are tiny sacs in the ovaries that contain immature eggs.
How It Works:
At the start of each menstrual cycle, FSH levels rise, prompting the ovaries to develop follicles. As these follicles grow, they produce another hormone called oestrogen. When oestrogen levels rise, it signals the body to reduce FSH production, preventing too many follicles from maturing at once.
Why It Matters:
FSH levels can indicate a woman’s ovarian reserve, which is the quantity and quality of her remaining eggs. High or low FSH levels can be a sign of fertility issues like polycystic ovary syndrome (PCOS) or ovarian insufficiency.
Luteinising Hormone (LH)
What It Does:
LH is also produced by the pituitary gland and works closely with FSH. It plays a key role in triggering ovulation, the process where a mature egg is released from the ovary.
How It Works:
Mid-cycle, a surge in LH occurs, causing the dominant follicle to release its mature egg into the fallopian tube, where it can be fertilised by sperm. After ovulation, LH helps form the corpus luteum, a temporary structure that produces progesterone to support early pregnancy.
Why It Matters:
If you want to know what hormone makes you fertile, you will want to look into LH. The LH surge is a key indicator of fertility and tracking it can help women identify their most fertile days. Ovulation predictor kits measure this surge to help determine the best time for conception.
Oestrogen (Oestradiol)
What It Does:
Oestrogen, mainly produced by the ovaries, is essential for regulating the menstrual cycle. It helps mature the egg and prepares the uterus for a possible pregnancy.
How It Works:
During the first half of the cycle (the follicular phase), rising oestrogen levels signal the growth of the uterine lining, making it thick and nutrient-rich. This prepares the uterus for the potential implantation of a fertilised egg.
Why It Matters:
Oestrogen levels affect many aspects of fertility. Too little oestrogen can prevent ovulation, while too much can cause problems like endometriosis or fibroids, which can affect a woman's ability to conceive. Symptoms of low oestrogen include dry skin, tender breasts, trouble concentrating, vaginal dryness and irregular periods.
Progesterone
What It Does:
Progesterone is a hormone created after ovulation by the corpus luteum. It helps maintain the uterine lining, making it ready for a fertilised egg to implant and start growing.
How It Works:
After the egg is released, progesterone levels rise, keeping the uterine lining thick and stable. If pregnancy occurs, progesterone continues to support the developing embryo. If not, progesterone levels drop, causing the uterine lining to shed (menstruation) and the cycle begins anew.
Why It Matters:
Low progesterone levels can lead to issues with implantation and early pregnancy loss. It is often tested when investigating fertility issues or recurrent miscarriages. Some signs of low progesterone include irregular periods, mood changes, hot flashes and trouble sleeping.
Human Chorionic Gonadotropin (hCG)
What It Does:
hCG is known as the pregnancy hormone because it is produced by the placenta soon after a fertilised egg implants in the uterus. It is the hormone that’s detected in pregnancy tests.
How It Works:
Once the embryo implants, it starts releasing hCG. This hormone signals the body to maintain the corpus luteum, which keeps producing progesterone to support the early stages of pregnancy until the placenta takes over around 11 weeks.
Why It Matters:
High levels of hCG indicate a healthy pregnancy, while low levels can be a sign of issues such as ectopic pregnancy or potential miscarriage.
To understand how these hormones interact, it helps to know the two main phases of the menstrual cycle:
Follicular Phase (Day 1 to Ovulation)
- Hormones Involved: FSH and Estrogen
- What Happens: FSH stimulates follicle growth and oestrogen thickens the uterine lining.
- Goal: Prepare the body to release a mature egg.
Luteal Phase (Post-Ovulation to Start of Next Period)
- Hormones Involved: LH, Progesterone and hCG (if pregnancy occurs)
- What Happens: Progesterone stabilises the uterine lining. If pregnancy occurs, hCG maintains progesterone production.
- Goal: Support a potential pregnancy.
Understanding your fertility hormone levels can be key to improving your chances of conception. Methods like monitoring basal body temperature, tracking cervical mucus and using ovulation predictor kits can help you identify your most fertile days.
You can also speak to your doctor to get a fertility home test, which is a blood test, as this can give you a detailed picture of your hormonal health.
What are the signs of hormonal imbalance?
- Irregular periods
- Mood swings
- Acne
- Poor sleep
- Fatigue
- Weight gain/loss
- Skin changes
- Brain fog
- Breast changes
- Hair loss
- Muscle aches and weakness
- Increased hunger and thirst
- Sensitivity to heat or cold
- Headaches
- Joint pain
- Darkened skin
What hormone imbalance causes infertility?
Can hormonal imbalance affect pregnancy? Most definitely! Hormone imbalances can affect your ability to get pregnant. Balanced hormone levels are crucial for normal ovulation and sperm production. Imbalances in any of these key hormones can disrupt the reproductive process, making it harder to get pregnant.
- Luteinising Hormone (LH): High levels of LH are often linked to polycystic ovary syndrome (PCOS), a condition that can prevent regular ovulation, making it harder to conceive. Low LH levels can reduce the body’s ability to release eggs in women or produce sperm in men, both of which are necessary for pregnancy.
- Follicle-Stimulating Hormone (FSH): If FSH levels are off balance, it can disrupt the growth of these follicles, leading to problems with ovulation (the release of an egg).
- Oestrogen: Is high oestrogen bad? When estrogen levels are too high or too low, it can lead to irregular periods or even anovulation (when no egg is released), making it difficult to conceive.
- Progesterone: Low levels can lead to irregular periods and may make it harder for a fertilised egg to implant in the uterus.
- Thyroid-Stimulating Hormone (TSH): The thyroid gland helps regulate your body's metabolism and TSH controls the thyroid. Imbalances in TSH can affect your menstrual cycle, causing irregular periods or even preventing ovulation, leading to infertility.
- Testosterone: In men, low testosterone may reduce sperm production, affecting fertility. In women, high testosterone levels, often seen in conditions like PCOS, may interfere with the hormones needed for ovulation.
How can I balance my hormones for fertility?
- Eat protein with every meal to feel full longer and support hormone production.
- Cut down on sugar and refined carbs to prevent hormone imbalances like high insulin.
- Limit alcohol as it can raise oestrogen levels and disrupt hormone balance.
- Include hormone-supporting foods like turmeric, avocados, leafy greens and eggs.
- Swap coffee for green tea to help lower insulin levels.
- Improve gut health with fermented and high-fibre foods for better hormone regulation.
- Get enough sleep to allow your body to properly produce hormones.
- Consider supplements like Vitamin D, B6 and adaptogenic herbs to support hormone health.
- Eat more fibre to help your body flush out excess hormones.
- Exercise regularly and try yoga or meditation to reduce stress and balance hormones.
Hormonal imbalances can disrupt the menstrual cycle and make conception difficult. Common factors that affect hormone levels include:
- Age: Fertility declines as a woman ages, particularly after 35.
- Stress: High stress can interfere with hormone regulation, leading to irregular cycles.
- Weight: Both underweight and overweight conditions can disrupt hormone balance.
- Medical Conditions: PCOS, thyroid disorders and diabetes can affect hormone production.
End Note
Hormones are the unsung heroes of fertility, guiding every step of the process from egg maturation to pregnancy maintenance. If you are trying to conceive, knowing how these hormones work and tracking their levels can provide valuable insights and improve your chances of success.
For anyone facing fertility issues, such as getting closer to menopause age, talk with your doctor to see if there are any potential treatment options to help you on your journey to parenthood.