How the Female Reproductive System Works

Female fertility depends on a coordinated system involving:

• Hormonal signalling between the brain and ovaries

• Egg development and ovulation

• Fallopian tube function

• A receptive uterine lining

• Healthy cervical mucus

Any disruption can impact the ability to conceive.

The Menstrual Cycle and Ovulation

Each month, the ovaries recruit follicles under the influence of FSH. At mid-cycle:

• A surge in LH triggers ovulation

• The egg is released and captured by the fimbrial end of the tube

• Fertilisation occurs in the tube

• The embryo travels to the uterus and must implant into a healthy lining

Ovulation Disorder (25% of Female Infertility)

Common causes:

• PCOS - androgen excess, insulin resistance, anovulation

• Hypothalamic dysfunction - stress, low weight, excessive exercise

• POI - early depletion of ovarian follicles

• Thyroid or prolactin disorders - impair hormonal balance

Ovulation can be evaluated with ovulation kits, blood tests, or ultrasound.

Tubal Factors

The fallopian tubes are essential for egg pick-up, fertilisation, and embryo transport. Tubal issues can occur due to:

• Pelvic inflammatory disease (e.g: chlamydia, gonorrhoea)

• Endometriosis

• Prior pelvic surgery

• Hydrosalpinx

Testing includes:

• HSG - Hysterosalpingogram 

• HyCoSy - Hysterosalpingo-Contrast Sonography

• Laparoscopy

Uterine Factors

A healthy uterine cavity is critical for implantation. Common uterine causes of infertility:

• Fibroids (especially submucosal)

• Polyps

• Congenital anomalies (septate, bicornuate uterus)

• Asherman’s syndrome (intrauterine adhesions)

• Chronic endometritis

• Thin endometrium

Assessment may include ultrasound, saline infusion sonography, hysteroscopy, or MRI.

Hormonal Factors

Disruptions in the hormonal axis can affect ovulation and implantation.

Key conditions include:

• Hypothyroidism and hyperthyroidism

• Hyperprolactinaemia

• Insulin resistance

• Luteal phase insufficiency

Age and Female Fertility

Egg quantity and quality decline with age.

• Peak fertility occurs in the 20s

• Decline accelerates after 35

• By 40, natural conception per cycle is <5%

Aneuploidy increases with age, reducing fertilisation and increasing miscarriage risk. Egg freezing offers an option to preserve fertility potential.

Medical Conditions Affecting Female Fertility

• Endometriosis

• PCOS

• Thyroid disease

• Diabetes

• Autoimmune disease

• Prior chemotherapy or radiotherapy

Fertility preservation should be discussed prior to cancer treatment.

When to Seek Fertility Assessment

You should consider seeing a fertility specialist if:

• <35 and trying for >12 months

• ≥35 and trying for >6 months

• Irregular or absent periods

• Known PCOS, endometriosis, thyroid disease

• Past pelvic surgery or infection

• Considering egg freezing or donor conception

Early assessment allows:

• Timely diagnosis

• Targeted treatments

• The best chance of achieving pregnancy

• Planning around age-related fertility changes

Fertility is a shared process - influenced by the health, hormones, genetics, and lifestyle of both partners.

Most fertility issues can be diagnosed, supported, or treated effectively with modern reproductive medicine.

Dr Rebecca Mackenzie-Proctor offers:

• Comprehensive fertility assessments

• Preconception optimisation programs

• Female and male fertility evaluations

• Ovulation tracking and cycle monitoring

• Sperm optimisation programs

• Egg freezing

• IVF, ICSI, IUI

• Donor services

• Compassionate, personalised guidance at every stage

If you’re preparing for pregnancy or navigating fertility concerns, we’re here to support your next steps.