Optimizing Natural Intercourse


This section is for couples who are working on trying to achieve a pregnancy naturally through timed intercourse.

The Fertile Window


The most fertile time in a women’s menstrual cycle is generally the six days prior to and including the day of ovulation (called the “fertile window”), though the length of this window may vary somewhat from woman to woman. The last two days just prior to ovulation are the times of highest fertility during this window. Intercourse at other times outside of this six-day window are less likely to result in a pregnancy, although conception can still occur in some circumstances.

Studies have shown that frequent intercourse, every one to two days, during the fertile window results in the highest pregnancy rates. No significant difference in pregnancy rates has been shown in studies comparing intercourse every day with intercourse every other day. The American Society of Reproductive Medicine therefore recommends that natural fertility can be maximized in most couples with regular intercourse (every one to two days) beginning after the woman’s menstrual flow has stopped and continuing through the time of ovulation (see the next section for how to predict ovulation).

However, a strict regimen of timed intercourse can cause significant stress and relationship strain in some couples. If this is a factor for you, know that a slightly decreased rate of intercourse during this time—two to three times per week—yields nearly equivalent rates of pregnancy.

Methods of Predicting Ovulation


Counting Backward from the Start of Menstruation

Day 1 of the menstrual cycle, which is the first day of full menstrual flow, typically occurs fourteen days after ovulation. If a woman’s cycles are very regular, this can be used to help predict the next month’s day of ovulation.


Basal Body Temperature

Starting approximately two days after ovulation, there is a sustained temperature increase of about 1°F that can be detected when the woman measures her body temperature each morning before rising. If a woman’s cycles are very regular, then charting basal body temperature can help predict ovulation.


Cervical Mucus

The cervical mucus typically becomes slippery and clear and increases in volume around the time of ovulation, starting to increase about five or six days before ovulation and peaking within two or three days of ovulation. Women can check the consistency of their cervical mucus by examining the discharge from the vagina or inserting a clean finger into the vagina. However, ovulation can occur without obvious cervical mucus changes.


Physical Symptoms

In many women, physical symptoms such as headaches, breast tenderness, mood swings, or changes in libido occur approximately seven to ten days prior to the menstrual period. Mittelschmerz, which is lower abdominal or pelvic pain on one side, is associated with ovulation in some women. However, determining ovulation on the basis of these symptoms is typically accurate only about half of the time.


Ovulation Detection Kits

Ovulation detection kits that measure luteinizing hormone (LH) in a woman’s urine can be obtained at drugstores without a prescription. A woman tests her urine every day with one of the strips included in the kit. When the urinary LH reaches a certain level (called LH surge), the test strip changes color. Ovulation typically occurs within two days of the LH surge. Clear Plan Easy and OvuKit One-Step are two good brands that are widely available. Be aware, though, that even with a good-quality kit, there is about a 7 percent false positive rate per cycle, with the kit incorrectly identifying the day of ovulation.

Follow the instructions on whichever kit you have purchased. Most recommend starting testing seventeen to eighteen days prior to the predicted first day of the woman’s period. For example, for a woman with a twenty-eight-day cycle, testing could begin on day 10 or 11. Generally, it is best to do the test between 10:00 a.m. and 2:00 p.m. unless the directions specify otherwise. Once the color change is seen, it is not necessary to check further during that cycle.


If your partner is taking clomiphene (Clomid), the ovulation detection kits can still be used, though with some modifications. The kit can provide inaccurate results if it’s used on the days when she is actively taking the clomiphene.

      1) A woman taking clomiphene on days 3 through 7 of her cycle should start checking for an LH surge on day 10.

      2) A woman taking clomiphene on days 5 through 9 of her cycle should start checking for an LH surge on day 12.


For further information about using an ovulation detection kit if a woman is taking clomiphene, see the gynecologist or infertility specialist who prescribed the medication.

Position During Intercourse


There are plenty of theories out there about how to increase your chances of natural conception with particular positions and techniques, such as having the woman remain lying on her back for a period of time following intercourse. Some also say that you can improve your chances of having a boy or a girl depending on the position you use. The American Society of Reproductive Medicine has reviewed the available data and found that technique and position during intercourse do not make a difference in terms of either improved fertility or the chances of having a boy or girl. And women do not need to stay on their backs following ejaculation, as studies have shown that sperm are present within the cervical channels within seconds of ejaculation.