Shettles Method: Can You Choose a Boy or Girl Baby?

Author: Ian C. Langtree - View Credentials
Published: 11 Nov 2013 - Updated: 5 Nov 2026
Publication Type: Informative

Table of Contents:
Synopsis - Definition - Overview - FAQs - Insights, Updates - Related Content

Synopsis

This information looks at the Shettles method, the best-known home approach for trying to conceive a boy or a girl by timing sex around ovulation, and compares its claims with the evidence. It explains ovulation, the fertile window and how a baby's sex is decided by X or Y sperm, then sets out the method's recommendations on timing, position and abstinence. A study of 221 women published in the New England Journal of Medicine found that timing intercourse in relation to ovulation had no practical influence on the sex of the baby. The page also warns against the method's douching advice and explains the only reliable medical options. It is useful for couples planning a pregnancy, including people with disabilities or genetic conditions who want accurate information rather than folklore.

At a Glance

• 1 - The egg survives for only about a day after it is released.
• 2 - A baby's sex is decided at conception by whether the sperm carries an X or a Y chromosome.
• 3 - Limiting sex to certain days to choose a baby's sex can make it take longer to get pregnant.
• 4 - Charts like the Chinese gender predictor are entertainment only and are no more accurate than a coin toss.

Topic Definition

Shettles Method

The Shettles method is a set of home practices proposed by American physician Landrum Shettles for trying to influence whether a couple conceives a boy or a girl, mainly by timing intercourse closer to or further from ovulation and by changing position, abstinence and vaginal acidity. It is based on the idea that sperm carrying a Y chromosome are faster but shorter-lived than those carrying an X chromosome. Research has not shown that the method changes the chance of having a boy or a girl.

Overview

Many couples hope to influence whether they have a boy or a girl, and home methods that promise to tip the odds have circulated for decades. The best known is the Shettles method, named after American physician Landrum Shettles. This page explains what the method recommends, what the research actually shows, and which advice is unsafe, so that couples can make informed choices and avoid spending money or taking risks on methods that do not work.

Ovulation and Conception Basics

Ovulation is the release of an egg from an ovary. In a typical 28-day cycle it happens around day 14, controlled by luteinizing hormone and follicle-stimulating hormone, although timing varies from woman to woman and month to month. The egg survives for about a day after release, while sperm can survive for several days, so the fertile window is the six days ending on the day of ovulation [Wilcox et al., 1995]. Conception happens when a sperm fertilizes the egg, and the baby's sex is decided at that moment: sperm carrying an X chromosome produce a girl, and sperm carrying a Y chromosome produce a boy. You can estimate your fertile days with an ovulation calculator.

What the Shettles Method Claims

Shettles proposed that Y sperm are smaller and faster but shorter-lived, and that X sperm are larger, slower and hardier. From that idea, the method recommends:

• For a boy: sex as close to ovulation as possible, deeper penetration, and a longer gap between ejaculations beforehand to raise the sperm count.
• For a girl: sex two to four days before ovulation, then stopping, with more frequent sex earlier in the cycle.
• Other suggestions, such as loose underwear for the man when trying for a boy, or the woman avoiding orgasm when trying for a girl, which have no scientific basis.

What the Research Shows

The idea that timing intercourse can choose a baby's sex has been tested and has not held up. In a study of 221 healthy women who were trying to conceive and who recorded intercourse while ovulation was measured from daily urine samples, researchers found that for practical purposes, the timing of intercourse in relation to ovulation had no influence on the sex of the baby [Wilcox et al., 1995]. Later research has also not confirmed the supposed size and speed differences between X and Y sperm. The chance of having a boy or a girl remains close to even for every pregnancy, whatever method is used at home.

Trying these methods can still have a cost. Limiting sex to a few days, or avoiding the most fertile days, can make it take longer to get pregnant, which matters most for couples who are older or already having difficulty conceiving.

Douching Is Not Safe or Effective

Shettles also suggested vinegar or baking soda douches to change vaginal acidity before sex. Doctors recommend that women do not douche. Douching upsets the normal balance of bacteria that protects the vagina, is linked to vaginal infections and sexually transmitted infections, and can lead to problems getting pregnant [Office on Women's Health, 2021]. It should never be used to try to choose a baby's sex.

Medical Sex Selection

The only reliable ways to select a baby's sex involve in vitro fertilization with genetic testing of embryos, which is expensive, invasive, and restricted or banned for non-medical reasons in many countries. It is mainly used to avoid serious genetic conditions that affect one sex, such as some forms of muscular dystrophy and hemophilia. Couples with a family history of such a condition should ask their doctor about genetic counseling.

Gender Prediction Charts

Charts such as the Chinese gender predictor, which claims to forecast the baby's sex from the mother's lunar age and month of conception, are entertainment only and are no more accurate than a coin toss. An ultrasound or prenatal blood test is the reliable way to learn the baby's sex during pregnancy.

Frequently Asked Questions

Who was Landrum Shettles?

Landrum Shettles was an American obstetrician and fertility researcher who popularized his sex selection theories in the book How to Choose the Sex of Your Baby, first published in 1970.

Is the chance of having a boy really 50 percent?

It is close. Slightly more boys than girls are born, at a natural ratio of about 105 boys for every 100 girls.

Does diet affect the sex of a baby?

There is no reliable evidence that eating certain foods or changing body acidity through diet changes a baby's sex.

When can I find out the sex of my baby?

A prenatal blood test can show the baby's sex from about 10 weeks of pregnancy, and an ultrasound can often show it from around 18 to 20 weeks.

Do some families tend to have more boys or girls?

Some families seem to, but large studies suggest that the sex of earlier children has little or no effect on the sex of the next child.

Is sex selection legal?

Laws vary. Many countries ban sex selection for non-medical reasons, while in the United States it is not banned but is offered only by some fertility clinics.

Are ovulation tests reliable?

Home ovulation tests detect the rise in luteinizing hormone that comes a day or two before ovulation, and they are a useful guide for timing sex to get pregnant.

When should we see a doctor about trouble getting pregnant?

See a doctor after 12 months of trying, or after 6 months if the woman is 35 or older, or sooner if there are known health problems.

References

• Office on Women's Health, U.S. Department of Health and Human Services. (2021). Douching.
• Wilcox, A. J., Weinberg, C. R., and Baird, D. D. (1995). Timing of sexual intercourse in relation to ovulation: Effects on the probability of conception, survival of the pregnancy, and sex of the baby. New England Journal of Medicine, 333(23), 1517 - 1521.

Insights, Analysis, and Developments

Editorial Note: Wanting a son or a daughter is natural, but no home method can reliably choose a baby's sex, and the chances stay close to even for every pregnancy. The Shettles method itself is mostly harmless if used only for timing, though it can delay conception for couples who skip their most fertile days. Its douching advice is not harmless, and should be ignored. For families with a serious genetic condition that affects one sex, a genetic counselor can explain the medical options and their limits. For everyone else, the most useful advice is to focus on a healthy pregnancy, using an ovulation calculator to find the fertile window and seeing a doctor if pregnancy does not happen within a year, or within six months for women over 35.

Author Credentials: Ian C. Langtree is a writer, editor, and the founder and Editor-in-Chief of Disabled World, which he established in 2004 as one of the longest-running independent resources for disability news and information. Over more than two decades, he has written and edited thousands of articles on disability rights, health, accessibility, and assistive technology. Drawing on a global perspective shaped by extensive travel and lived experience, Ian is a committed advocate of the Social Model of Disability, the framework developed by disabled activists in the 1970s that focuses on removing societal barriers rather than on individual impairments. His writing is grounded in that framework and in a lasting commitment to disability rights, accessibility, and social inclusion. To learn more about Ian's background, expertise, and accomplishments, visit his full biography.