Hormonal Imbalances
Common Fertility Problems
Key Points
- Hormonal imbalances can impair egg and sperm development, ovulation, implantation and pregnancy.
- Blood tests can inform if there is a hormonal imbalance.
- Medication can be used in most cases to correct hormonal imbalance.
Hormones in the Reproductive System
The reproductive system relies on several hormones which levels go up and down at different phases of the cycle. The HPG axis refers to the relationship between the hypothalamus, the pituitary gland and gonads (ovaries and testicles) that produce hormones. There is a feedback loop mechanism in the HGP axis, with hormones affecting production levels of other hormones. Hormones allow for eggs and sperm to develop and mature, for ovulation to occur, fertilization, implantation and development of the embryo.Hormonal problems are the most common causes of failure to ovulate (anovulation). It can also cause implantation failure and miscarriage.
Hormonal problems can be at any point of the HPG axis:
- Hypothalamus (which releases gonadotropin-releasing hormone)
- Pituitary gland (which releases LH and FSH)
- Gonads (which release oestradiol, progesterone and testosterone)

What Causes Hormonal Disturbances?
- Tumours
- Extreme stress
- Being over or under weight
- Strenuous exercise
- PCOS
- Over or underactive thyroid
- Diabetes
- Premature ovarian insufficiency
Diagnosis
Diagnosis of hormonal imbalances is made with blood tests at certain phases of the cycle. Medication can be used in most hormonal imbalances to return values to normal range.Oestradiol
Oestradiol is produced by the ovaries, adrenal gland and placenta. It’s one of the most important hormones, responsible for different functions:- Female reproductive growth
- Development of secondary sexual characteristics
- During menstrual cycle, to maintain the eggs inside a female’s ovaries and trigger a message to the pituitary gland to produce LH when eggs are ready.
- During pregnancy, to maintain the pregnancy.
- For bone health.
Progesterone
After ovulation, the ruptured follicle becomes corpus luteum and produces progesterone. Progesterone is important to prepare the uterus for implantation and to maintain the pregnancy.FSH
Follicle Stimulating Hormone is made by your pituitary gland. FSH plays an important role in sexual development and functioning.In women, FSH helps control the menstrual cycle and stimulates the growth of eggs in the ovaries. In men, FSH helps control the production of sperm.
LH
Luteinizing Hormone (LH) stimulates the ovaries to release an egg (ovulation). LH values increase just before ovulation – called the LH surge.A LH surge value of 2.5 above the baseline values is needed for ovulation to happen.