On average most couples will have conceived within six months once they stop using contraception and are having regular unprotected sex. 'Regular' sex is defined as every two to three days.
A high percentage (around 35%) will have conceived within one month, which is why it is ideal to start taking folic acid before you stop contraception. It takes three months for folic acid to build up to the required amount in your body to give maximum protection from spina bifida to your baby.
One study into time to pregnancy followed women who were trying to get pregnant by timing sex to when they believed they were fertile. Of the 346 women in the study, 310 conceived in the first year. The breakdown was like this:
- 38% pregnant within1 month
- 68% pregnant within 3 months
- 81% pregnant within 6 months
- 92% pregnant within 12 months.
Age and conception
Fertility declines with age. The mothers age is most important but the father's fertility also declines with age. Age also effects the health of the pregnancy with the risk of miscarriage and pregnancy complications increasing after the woman reaches 35.
Likelihood of conceiving within six months depending on mother's age
Starting at about age 32, a woman’s chances of conceiving decrease gradually but significantly. From age 35, the fertility decline speeds up.
- At age 30 women have a 20% chance of conceiving every month
- At age 40 women have a 5% chance of conceiving every month.
When should I get help?
After a year of trying without conceiving, it is recommended that you talk to your GP.
If you are over 36 or have a known fertility issue, such as PCOS or endometriosis, then you should see your doctor earlier.
Sozou PD,Hartshorne GM (2012) Time to Pregnancy: A Computational Method for Using the Duration of Non-Conception for Predicting Conception. Plos One. Published: October 4, 2012 https://doi.org/10.1371/journal.pone.0046544
Gnoth C, Godehardt D et al (2003) Time to pregnancy: results of the German prospective study and impact on the management of infertility, Human Reproduction, Volume 18, Issue 9, 1 September 2003, Pages 1959–1966, https://doi.org/10.1093/humrep/deg366
RCOG (2011) Reproductive Ageing. Scientific Advisory Committee. Opinion Paper 24. London: Royal College of Obstetricians and Gynaecologists. www.rcog.org.ukHide details
ℹLast reviewed on April 30th, 2018. Next review date April 30th, 2021.