Weight and fertility

Revised 2015


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How do I know if I am a good weight for pregnancy?

One of the easiest ways to determine if you are underweight or overweight is to calculate your body mass index (BMI). There are many tables available online (search term: BMI table). Enter your height and weight into the tool to see your BMI.

What is a normal BMI?

A BMI between 19 and 24 is considered normal; less than 19 is considered underweight. A BMI between 25 and 29 is considered overweight and greater than 30 places you in the category of obese.

How does weight affect fertility in women?

Many underweight, overweight, and obese women have no problem getting pregnant. But others will have problems conceiving, most often due to ovulation problems (failure to release eggs from the ovaries).

A BMI of 18.5 or less (underweight) often causes irregular menstrual cycles and may cause ovulation to stop altogether. A BMI of 17.5 or less could indicate an eating disorder. Women at less than normal BMI should work with their doctor to understand the cause of this situation, and develop strategies to correct it.

A BMI in the obese range may also lead to irregular menstrual cycles and ovulation. However, even obese women with normal ovulation cycles have lower pregnancy rates than normal weight women, so ovulation isn’t the only issue. A visit to a healthcare professional before becoming pregnant can help identify other disorders related to obesity that impact pregnancy such as thyroid disease, insulin resistance, and diabetes.

Does obesity affect the chance of getting pregnant with treatment and having a healthy baby?

There is good evidence that obesity lowers the success rates of in vitro fertilization (IVF). Studies have shown lower pregnancy rates and higher miscarriage rates in obese women. Obese women are at an increased risk for developing pregnancy-induced (gestational) diabetes and high blood pressure (pre-eclampsia). Obese women also have a higher chance of delivering by cesarean section. Children of obese mothers are at increased risk of some birth defects and having a high birth weight.

Are there fertility problems in men with obesity?

Obesity in men may be associated with changes in testosterone levels and other hormones important for reproduction. Low sperm counts and low sperm motility (movement) have been found more often in overweight and obese men than in normal-weight men.

Should I try to lower my BMI if I am in the obese category before I try to get pregnant?

You should first consult with a healthcare provider. He or she will consider all factors, including your age and any other infertility factors, before making a recommendation about whether you should try to lose weight first. Changing your diet and lifestyle (for example, exercise) combined with a program that may provide group support is an effective step, but not always the appropriate first step if your age or your BMI is above 40. Weight loss surgery (bariatric surgery) is the most effective treatment for weight loss in women with a BMI greater than 40.

I have polycystic ovary syndrome (PCOS) and am overweight, will I need to do anything different?

PCOS is a very common condition in young women (about 8%–10%). Not all women with PCOS are overweight or obese, but many women with PCOS have signs of insulin resistance and/or obesity. A low-calorie diet and exercise  may lead to weight loss, regular menstrual cycles, and ovulation.

However, women with PCOS may require additional treatment to get  pregnant, including medications to decrease insulin resistance. These women  should seek the assistance of a reproductive endocrinology and  infertility  specialist. For more information about PCOS, please see the ASRM  fact  sheet titled Polycystic ovary syndrome. To find an infertility  specialist near  you, use the ASRM Find a Healthcare Provider tool on  ReproductiveFacts.org.

Weight

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SART Fertility Experts - Wellness and Fertility: Diet, Sleep and Exercise

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Preparing for In Vitro Fertilization (IVF): Lifestyle Factors

This SART micro-video discusses lifestyle factors that may affect in vitro fertilization, or IVF, outcomes.   Watch Video

Female Fertility

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SART Fertility Experts - Fertility Myths and Realities for Black Women

Black women are more likely to experience infertility and less likely to seek and receive timely treatment. Listen to the Episode
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SART Fertility Experts - Wellness and Fertility: Diet, Sleep and Exercise

Drs. Timothy Hickman and Rashmi Kudesia discuss the links between lifestyle and fertility. Listen to the Episode
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SART Fertility Experts - Preconception Counseling

This podcast episode covers the topic of preconception counseling.  Listen to the Episode
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Female Fertility Journey

If you've been trying to get pregnant for more than a year, you may have infertility. Infertility is a disease of the reproductive system that impairs one of the body's most basic functions: the conception of children.

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SART Fertility Experts - Endometriosis

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SART Fertility Experts - IVF: Cycles of Hope and Heartbreak

Does stress cause infertility or is it the other way round?  Listen to the Episode
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SART Fertility Experts - Fibroids and Fertility

Fibroids and their impact on fertility are discussed in this episode featuring Dr. Elizabeth Stewart, interviewed by host Dr. Brooke Rossi.  Listen to the Episode
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Infertility: an Overview (booklet)

Infertility is typically defined as the inability to achieve pregnancy after one year of unprotected intercourse. View the booklet
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Optimizing Natural Fertility

Before attempting pregnancy, a woman should make sure she is healthy enough for pregnancy by adopting a healthier lifestyle and taking prenatal vitamins. If she has a medical or genetic condition or risk of one, she should seek advice from a medical professional before conceiving (becoming pregnant) View the fact sheet
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Infertility

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Basic Infertility Evaluation

Dr. Roger Lobo of the American Society for Reproductive Medicine discusses the various methods to evaluate infertility. Watch Video
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Fibroid Tumors

An educational video that answers patient questions about the causes, symptoms, diagnosis and management of uterine fibroids. Watch Video
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Infertility Treatments

Dr. Roger Lobo of the American Society for Reproductive Medicine discusses the various treatments for infertility. Watch Video
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Understanding Fertility

In this video series, Dr. Roger Lobo explains the basics of infertility, including causes, treatments and coping methods. Watch Video
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Surviving the Roller Coaster Emotions of Infertility Treatment

The experience of infertility is a rollercoaster of hope and disappointment. Treatment presents an opportunity for hope as well as a new set of challenges. Watch Video
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What is Recurrent Pregnancy Loss (RPL)?

This is a condition when a woman has 2 or more clinical pregnancy losses (miscarriages) before the pregnancies reach 20 weeks. View the fact sheet
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Hypothyroidism and pregnancy: what should I know?

Hypothyroidism (underactive thyroid) is when the thyroid gland produces less  thyroid hormone than it should. View the Fact Sheet
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Female Cancers, Cryopreservation, and Fertility

Yes! New technology lets your doctor remove and freeze eggs, fertilized eggs (embryos), or ovarian tissue before treating your cancer. This way, you may be able to have children after your treatment. View the Fact Sheet
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Weight and fertility

One of the easiest ways to determine if you are underweight or overweight is to calculate your body mass index (BMI). View the fact sheet
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Stress and infertility

It is not clear how exactly stress impacts fertility. Read the Fact Sheet
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Am I Ovulating?

Ovulation is the release of an egg from a woman’s ovaries and is essential for getting pregnant. View the Fact Sheet
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Dilation and Curettage (D&C)

“Dilation and curettage” (D&C) is a short surgical procedure that removes tissue from your uterus (womb). You may need this procedure if you have unexplained or abnormal bleeding or if you have delivered a baby and placental tissue remains in your womb. View the Fact Sheet
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Evaluation of the Uterus

If you haven’t been able to get pregnant after trying for 6 months, some tests can be done to help find the reason. Your doctor may test your hormone levels, your partner’s sperm, and your reproductive organs (ovaries, fallopian tubes, and uterus [womb]). View the Fact Sheet
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Abnormalities of the Female Reproductive Tract (Müllerian Defects)

Sometimes the uterus and fallopian tubes may not form like they should. These malformations are called müllerian anomalies or defects. Müllerian anomalies may make it difficult or impossible to become pregnant. View the Fact Sheet
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Conditions Treated with Adnexal Surgery

Surgery can be used to treat problems with your ovaries or fallopian tubes such as cysts, endometriosis or infections. Adnexal surgery involves any of the organs that are on the sides of (“next to”) the uterus (womb), such as the fallopian tubes and ovaries.

  View the Fact Sheet
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Diagnostic Testing for Female Infertility

An evaluation of a woman for infertility is appropriate for women who have not become pregnant after having 12 months of regular, unprotected intercourse. View the Fact Sheet
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Endometriosis (booklet)

Women with endometriosis may experience infertility, pelvic pain, or both. This booklet will describe options for diagnosing and treating pain or infertility that may be attributed to endometriosis. View the Booklet
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Fertility Drugs And The Risk of Multiple Births

Infertility treatments that cause multiple eggs to develop make it more likely that you will become pregnant with twins, triplets, or more. This is called multiple gestation. View the Fact Sheet
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Ovulation Detection

Ovulation, the release of an egg from its follicle in one of a woman’s two ovaries, is one of the most important factors in conceiving a child. View the fact sheet
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FAQ About Infertility

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Female Fertility Infographics

ASRM has prepared infographics to illustrate the subject of Female Fertility better. View the Infographics
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Ovarian Reserve Infographics

ASRM has prepared infographics to illustrate the subject of Ovarian Reserve better. View the Infographics

Male Fertility/Andrology

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SART Fertility Experts - Wellness and Fertility: Diet, Sleep and Exercise

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Male Fertility Journey

About 20% of infertility cases are due to a male factor alone. Another 30% involves both male and female factors.

View the Patient Journey
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SART Fertility Experts - Urology and Male Reproductive Health

Male infertility is less often discussed than female infertility. Dr. Ajay Nangia discusses when a man should seek help with conceiving.
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SART Fertility Experts - Male Factor

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SART Fertility Experts - IVF: Cycles of Hope and Heartbreak

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SART Fertility Experts - Male Fertility

Did you know that up to 40% of infertile couples suffer from male factor infertility? Listen to the Episode
Patient Ed Icon

Infertility: an Overview (booklet)

Infertility is typically defined as the inability to achieve pregnancy after one year of unprotected intercourse. View the booklet
Patient Ed Icon

Optimizing Natural Fertility

Before attempting pregnancy, a woman should make sure she is healthy enough for pregnancy by adopting a healthier lifestyle and taking prenatal vitamins. If she has a medical or genetic condition or risk of one, she should seek advice from a medical professional before conceiving (becoming pregnant) View the fact sheet
Patient Ed Icon

Optimizing Male Fertility

About 20% of infertility cases are due to a male factor alone. Another 30% involves both male and female factors. View the fact sheet
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Male Fertility and Infertility - a patient education video

Male Factor Infertility is responsible for about 30% of infertility cases and can contribute infertility to an additional 20% of cases. Watch Video
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Infertility

Infertility is the result of a disease (an interruption, cessation, or disorder of body functions, systems, or organs) of the male or female reproductive tract which prevents the conception of a child or the ability to carry a pregnancy to delivery.  Watch Video
Videos Icon

Basic Infertility Evaluation

Dr. Roger Lobo of the American Society for Reproductive Medicine discusses the various methods to evaluate infertility. Watch Video
Videos Icon

Infertility Treatments

Dr. Roger Lobo of the American Society for Reproductive Medicine discusses the various treatments for infertility. Watch Video
Videos Icon

Understanding Fertility

In this video series, Dr. Roger Lobo explains the basics of infertility, including causes, treatments and coping methods. Watch Video
Videos Icon

Surviving the Roller Coaster Emotions of Infertility Treatment

The experience of infertility is a rollercoaster of hope and disappointment. Treatment presents an opportunity for hope as well as a new set of challenges. Watch Video
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What is intracytoplasmic sperm injection (ICSI)?

A procedure called intracytoplasmic sperm injection (ICSI) can be done along with in vitro fertilization (IVF) if a sperm cannot penetrate the outer layer of an egg. Read the Fact Sheet
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Male cancer, cryopreservation, and fertility

This can be confusing since the terms are often used interchangeably in the media and casual conversation. View the fact sheet
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Male infertility evaluation: what do I need to know?

Infertility is the inability to achieve pregnancy after one year of unprotected sex. View the fact sheet
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Surgical techniques for sperm retrieval: what should I know?

As many as 10% to 15% of infertile men have no sperm in their ejaculate (the fluid released from the penis during orgasm). View the fact sheet
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Testosterone use and male infertility

Testosterone (also referred to as “T”) is a hormone produced in men by the testes (testicles). View the fact sheet
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Weight and fertility

One of the easiest ways to determine if you are underweight or overweight is to calculate your body mass index (BMI). View the fact sheet
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Stress and infertility

It is not clear how exactly stress impacts fertility. Read the Fact Sheet
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Sperm morphology (shape): Does it affect fertility?

The most common test of a man’s fertility is a semen analysis. View the fact sheet
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Spinal cord injury sperm retrieval

There are several reasons a man with a spinal cord injury (SCI) might have infertility. View the fact sheet
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Varicocele

A varicocele is a variation of normal anatomy in which veins in the scrotum (the sac that holds the testicles) become enlarged and sometimes even visible. View the fact sheet
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Causes of Male Infertility

Dr. Roger Lobo, of the American Society for Reproductive Medicine explains the causes of male infertility. Watch Video
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Fertility Options After Vasectomy

Vasectomy is currently one of the most common methods of sterilization in the United States. After your vasectomy, if you change your mind about having children, there are two procedures that can help you have a child with your partner. View the Fact Sheet
Info Icon

FAQ About Infertility

Infertility is not an inconvenience; it's a disease of the reproductive system that impairs the body's ability to perform the basic function of reproduction. Learn the facts
Infographic Icon

Male Fertility Infographics

ASRM has prepared infographics to illustrate the subject of  Male Fertility better. View the infographics

Polycystic Ovary Syndrome (PCOS)

Podcast Icon

SART Fertility Experts - PCOS

As the most common hormonal disorder in women, PCOS is a disruptive problem that impacts aspects of a woman’s health, including getting pregnant. 
Listen to the Episode
Patient Ed Icon

Hirsutism and Polycystic Ovary Syndrome (PCOS) (booklet)

Polycystic ovary syndrome (PCOS) is a condition in which the ovaries contain many cystic follicles associated with chronic anovulation (lack of ovulation) and overproduction of androgens (male hormones). View the booklet
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Ovarian drilling for infertility

Often, women with polycystic ovary syndrome (PCOS) do not have regular menstrual periods. View the fact sheet
Patient Ed Icon

Polycystic Ovary Syndrome (PCOS)

Polycystic ovary syndrome is a common hormone disorder that affects 5-10% of women. View the fact sheet
Patient Ed Icon

Conditions Treated with Adnexal Surgery

Surgery can be used to treat problems with your ovaries or fallopian tubes such as cysts, endometriosis or infections. Adnexal surgery involves any of the organs that are on the sides of (“next to”) the uterus (womb), such as the fallopian tubes and ovaries.

  View the Fact Sheet
Patient Ed Icon

Insulin-sensitizing agents and polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common reproductive disorder, affecting 5% to10% of women of reproductive age. View the Fact Sheet
Infographic Icon

Polycystic Ovary Syndrome Infographics

ASRM has prepared infographics to illustrate the subject of Polycystic Ovary Syndrome better. View the Infographics

Fact Sheets/Booklets

View more fact sheets and booklets written by the ASRM Patient Education Committee.
Patient Booklet teaser

Assisted Reproductive Technologies (booklet)

This booklet will help you understand in vitro fertilization (IVF) and other assisted reproductive technology (ART) that have become accepted medical treatments for infertility.
Patient Factsheet teaser

Hormonal Contraception

Hormonal contraceptives contain a progestin (progesterone medicine) with or without an estrogen.
Patient Factsheet teaser

What do I need to know about Zika virus and trying to have a baby?

Common symptoms include fever, rash, joint pain, conjunctivitis (red eyes), muscle pain, and headache.
Patient Booklet teaser

Third-Party Reproduction

The phrase “third-party reproduction” refers to involving someone other than the individual or couple that plans to raise the child (intended parent[s]) in the process of reproduction.

Resources For You

The American Society for Reproductive Medicine (ASRM) is committed to providing patients with the highest quality information about reproductive care.

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