How to Get Pregnant: Fertile Window, Timing, Lifestyle Tips and When to See a Doctor

For most couples, getting pregnant takes a little time. Even with perfect timing, the chance of conception in any single menstrual cycle is only about 20-25%. Understanding ovulation, improving general health and avoiding common myths can raise your chances and reduce stress.

Understand your cycle

• Day 1 of the cycle is the first day of your period.
• Ovulation, when an egg is released from the ovary, typically happens about 14 days before the next period. In a 28-day cycle it is around day 14, but in a 35-day cycle it is around day 21.
• An egg survives for only 12-24 hours, but sperm can survive for up to five days in the female reproductive tract.
• The fertile window is therefore about six days: the five days before ovulation and the day of ovulation. The two or three days before ovulation, plus ovulation day, are the most fertile.

Try our ovulation calculator for an estimate. Calendar methods are less accurate if your cycles are irregular. See irregular periods.

How to spot ovulation

• Cervical mucus: becomes clear, slippery and stretchy, like raw egg white, in the fertile days.
• Ovulation predictor kits (OPKs): urine strips that detect the LH surge 24-36 hours before ovulation. Start testing a few days before you expect ovulation.
• Basal body temperature: rises slightly (about 0.2-0.5 °C) after ovulation. It confirms that ovulation has happened but cannot predict it.
• Other signs: mild one-sided pelvic pain, breast tenderness or increased sex drive.

Tracking helps some couples but can cause stress. If it does, simply have sex regularly.

When and how often to have sex

• Every one to two days throughout the cycle, or at least every two days during the fertile window, gives the best chance. This does not reduce sperm quality.
• You do not need to time it down to the hour.
• Avoid lubricants that may harm sperm (some commercial lubricants, saliva); use fertility-friendly or oil-based such as mineral oil, canola oil if needed.
• No position is proven better, and lying down afterwards is optional.

Prepare your body before conception

• Take folic acid 400 micrograms daily, ideally starting at least a month before conception. A higher dose (5 mg) is advised for women with diabetes, epilepsy, obesity or a previous baby with a neural tube defect. Ask your doctor.
• Aim for a healthy weight. Both being underweight and overweight can affect ovulation. Use our BMI calculator and check BMI for Asians. Losing 5-10% of weight can restore ovulation in women with overweight and PCOS.
• Review medicines with your doctor, including those for epilepsy, high blood pressure, acne, thyroid or mental health, and herbal remedies.
• Check vaccinations, especially rubella and chickenpox, and have a cervical screening up to date.
• Control medical conditions such as diabetes, thyroid disease, high blood pressure and anaemia before pregnancy. See gestational diabetes and PCOS.
• Eat a balanced diet, with vegetables, fruit, pulses, fish, eggs, whole grains, and enough iron and calcium.
• Exercise moderately. Excessive training can disturb ovulation.
• Stop smoking, and avoid alcohol and recreational drugs. Smoking reduces fertility in both men and women.
• Limit caffeine to about 200 mg a day, equal to two cups of coffee.
• Manage stress and sleep. Stress does not usually prevent pregnancy by itself, but it can reduce sex drive and disrupt cycles.

Male fertility matters too

Male factors contribute to about a third to half of fertility problems. Men can improve sperm health by:

• Stopping smoking and heavy alcohol, and avoiding anabolic steroids and testosterone supplements
• Keeping a healthy weight
• Avoiding prolonged heat exposure to the testicles (hot baths, saunas, laptops on the lap)
• Treating infections and medical conditions, and reviewing medicines
• Eating a healthy diet and exercising moderately

A semen analysis is a simple, early test.

Common myths

• "You can only get pregnant on day 14." Ovulation timing varies, and the fertile window is about six days.
• "Fertility problems are always the woman's." Men are equally often involved.
• "Relax and it will happen." Stress alone is rarely the cause, but a medical check is useful if you are struggling.
• "Herbal fertility supplements work." Evidence is poor, and some are unsafe.

When to seek help

See a doctor (ideally together as a couple) if:

• You have been trying for 12 months with regular unprotected sex and the woman is under 35
• You have been trying for 6 months and the woman is 35 or older, or consult straight away at 40 or over
• Periods are irregular or absent, or you have pelvic pain, endometriosis, fibroids or PCOS
• You have had pelvic infection, previous surgery or repeated miscarriages
• The man has had testicular problems, surgery, cancer treatment or erection or ejaculation problems

What fertility tests involve

• Blood tests: ovulation hormones (progesterone in the second half of the cycle), thyroid, prolactin, AMH
• Pelvic ultrasound
• Tubal patency test: hysterosalpingogram (HSG) or scan
• Semen analysis

Treatment may include ovulation induction (such as letrozole), intrauterine insemination (IUI), IVF and treatment of underlying conditions.

Once you are pregnant

Take a test on or after the first day of your missed period, and read early pregnancy symptoms. Register with your antenatal clinic early, and use our due date calculator.

References

• NICE guideline CG156: fertility problems, assessment and treatment
• American Society for Reproductive Medicine: optimizing natural fertility
• World Health Organization: infertility fact sheet and laboratory manual for semen examination
• Wilcox AJ et al. Timing of sexual intercourse in relation to ovulation. New England Journal of Medicine, 1995