If you’re trying for a baby, you may think you need to have sex on the day you ovulate to increase your chances of conceiving – after all, it seems to make sense.  But like so many fertility myths, the truth is more complicated. 

It is true that an egg needs to be fertilised within 24 hours of being released from the ovary, and that might make you think that you have to have sex on the day you ovulate to conceive.  But sperm can survive in the fallopian tubes for up to seven days.  This means that your fertile window is the five days leading up to ovulation, plus the day you ovulate.  What’s more, this six-day fertile window doesn’t alter as you get older – a study of 782 couples found that nearly all pregnancies occurred within these six days, regardless of the ages of the couples.

It is still important to know when you ovulate, to establish when your fertile window is.  Studies have shown that this can be unpredictable, even if your cycle is usually regular.  Carole Gilling-Smith, Consultant Gynaecologist and Medical Director at the Agora Gynaecology & Fertility Centre, explains this is why some women need expert help in establishing when their fertile window is: “Women should ovulate exactly 14 days before their period starts, which means if you have a regular cycle you can predict your day of ovulation without needing to use ovulation predictor kits. For example, if your cycle is 28 days, then you ovulate on Day 14 (Day 28 minus 14); if your cycle is 31 days, you ovulate on Day 17 (Day 31 minus 14). If your cycle is irregular then the best way of knowing when you ovulate is to use a home urinary predictor kit, although in women with polycystic ovary syndrome this can be unreliable because they may have a persistently high level of the ovulation hormone LH (luteininsing Hormone) in their urine.”

Our experts at The Agora Clinic are happy to advise you on how you can boost your chances of conceiving – including when you need to be having sex!

To find out more about how our fertility experts can help you, call us on

01273 229410

We’re proud to announce that our Medical Director, Carole Gilling-Smith recently won a ‘Sussex Women In Business’ award.

We also won an innovation award for our fertility services!