When it comes to fertility, understanding the numbers can make a real difference to your chances of conception. Obstetrician and fertility expert Dr Kate Gowling from FertilitySA offers a clear-eyed breakdown of what women need to know when planning for a family.
Female fertility peaks at age 25 and begins to decline gradually from that point, with a more pronounced drop after 35. This decline is driven by both a reduction in egg numbers and a decrease in egg quality, which also corresponds with a higher risk of miscarriage and chromosomal abnormalities in embryos.
In practical terms, the statistics are worth knowing. Before the age of 30, a woman has roughly a 25 per cent chance of falling pregnant per cycle. Between 30 and 35 this drops to around 15 per cent, and between 35 and 40 it sits at approximately 12 per cent. After 40, the chance of natural conception per cycle falls to just five per cent.
Timing also plays a significant role. The fertile window spans from around five days before ovulation through to the day of ovulation itself. Intercourse every one to two days leading up to ovulation offers the best chance of conception, and tracking cervical mucous changes can help identify the most fertile days.
When it comes to egg reserve, Dr Gowling notes that the AMH blood test can provide a useful snapshot of where a woman's ovarian reserve sits relative to her age. Women are born with all the eggs they will ever have, and by age 30 only around 12 per cent of those remain. While AMH cannot predict the chance of pregnancy on its own, it can help inform decisions about when to start trying or whether further investigation is warranted.
For couples who do face challenges, treatment options range from ovulation induction and IUI through to IVF and laparoscopic surgery, depending on the underlying cause.
Dr Kate Gowling
She is passionate about providing high quality obstetric and gynaecologic care to the women of Adelaide, both operating and delivering at Ashford Hospital. Her special interests include obstetric care, infertility and miscarriage, abnormal uterine bleeding, and laparoscopic surgery.
