What Is Fertility?


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​​Dr. Ghazal is a double board certified fertility specialist, a Southern California native and an award-winning top doctor.
Sanaz Ghazal, M.D., F.A.C.O.G. Fertility / Reproductive Health / Obstetrics and Gynecology
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The word fertility may not be in your vocabulary until you’re trying to get pregnant, only to find it’s not as easy as you hoped. If you are unable to get pregnant, you may be struggling with infertility—and it’s quite common. According to the World Health Organization, between 48 million couples and 186 million individuals experience infertility every year[1].

But what encompasses fertility, exactly, and how do you know if you’re dealing with a fertility issue? Here’s everything you need to know.

What Is Fertility?

The definition of fertility is the ability to achieve a pregnancy, according to Chenchen Sun, M.D., an obstetrician and gynecologist at Tufts Medical Center. “This is different from fecundity, which is the ability to have a live birth,” she explains.

According to the American College of Obstetricians and Gynecologists (ACOG), a woman’s peak fertile years are between their late teens and late twenties. Around age 30, fertility may decline a bit, with it falling more rapidly by your mid thirties. While men are known to have a longer window of fertility than women, research shows that aging does have an impact on male sexual function, sperm parameters and fertility.

Causes of Infertility

Infertility is defined as the inability to get pregnant after one year of regular sexual intercourse without birth control, according to ACOG. Sometimes it’s easy to identify the causes of infertility, and other times it’s much harder.

Here are some of the most common causes of infertility, according to experts:

Not Ovulating or an Ovulation Disorder

In order to achieve a pregnancy, a person has to ovulate, which is defined as the time when the ovary releases an egg. If a person is not releasing an egg, there’s no way to achieve pregnancy.

“A common ovulation disorder is a hormone imbalance called polycystic ovarian syndrome (PCOS). This is a hormonal imbalance that women can be born with, and it tends to run in families,” explains Jennifer Makarov, M.D., a reproductive endocrinology and fertility specialist at New Hope Fertility. It is very common, she notes, and can cause ovulation to be irregular, which decreases your fertility.

Other causes of ovulation issues can include being overweight, underweight, having a hormonal disorder such as thyroid abnormalities or hyperprolactinemia and excessive physical and emotional stress.

Uterine Issues

Sometimes, infertility issues are related to the uterus. “Any structural abnormalities within the uterus itself may distort the uterine cavity,” says Dr. Sun. “Examples include fibroids [noncancerous growths in the uterus] and uterine septum [a condition where the uterus gets an extra wedge of tissue and runs down the middle of the uterus].”

Tubal Factor Infertility

Tubal factor infertility is when a person has damage in their fallopian tubes. “Examples can include a history of pelvic inflammatory disease, smoking or ectopic pregnancy,” says Dr. Sun.

Male Factor Infertility

Infertility is not exclusive to women. In fact, 40% to 50% of infertility cases are considered to be male factor[2]. “The top cause of male infertility is problems with sperm,” explains Amy Roskin, M.D., board-certified OB-GYN and chief medical officer of Seven Starling, a women’s health digital platform. “This could be a low number of sperm or problems with how they move. Lifestyle factors like alcohol consumption and smoking can negatively impact fertility.”


Age is another big cause of fertility issues. According to ACOG, for healthy couples in their twenties  or early thirties, the chances that a woman will become pregnant is about 25% to 30% in a menstrual cycle, and that percentage starts to decline in a woman’s thirties and more rapidly by age 37[3].

By 40, a woman’s chances of getting pregnant drop to less than 10% each menstrual cycle.

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Common Signs of a Fertility Problem

The top sign of a fertility problem is the inability to get pregnant after one year of trying if you’re under age 35, or six months of trying if you’re between the ages of 35 and 40. Other signs include:

  • A history of PCOS
  • Irregular periods
  • A history of endometriosis, as this can cause inflammation in the lining of the uterus, around ovaries or cysts
  • Low egg supply or reserve
  • Abnormal sperm
  • Recurrent pregnancy loss
  • Problems with the uterus

Healthy Habits to Boost Fertility

If you’re struggling with fertility issues, don’t wait—consult your doctor to find out what treatments are available. But in the meantime, there are some lifestyle changes you can make. These include:

Not Smoking

“Smoking decreases sperm quality very significantly. We see problems with shape and count in men who smoke,” explains Dr. Makarov. “It also decreases egg quality and supply. So, the number one thing you can do to boost and protect your fertility is not smoking.”

Maintaining a Healthy BMI

A high BMI has been associated with fertility issues, according to Dr. Makarov. She suggests getting adequate exercise and sleep along with adhering to a healthy diet including plenty of fruits, vegetables and minimally processed foods.

She adds that although exercising is very important, you don’t want to over-exercise. “I do see some patients who over-exercise, which can actually decrease their periods. It causes their body to stop ovulation, so you don’t want to over-exercise or do extreme exercise because that can be detrimental to your fertility,” she says.

Manage Stress

Not to put the pressure on, because we all know that thinking about eliminating stress can actually make us more stressed, but doing your best to manage your stress is a very good idea. “Managing stress and improving your diet may help,” says Dr. Roskin.

While the link between stress and pregnancy outcomes isn’t totally understood, one study found that women with a higher level of alpha-amylase in their saliva, which indicates stress, took longer to get pregnant[4]. So if you’re having a hard time getting pregnant, working to decrease stress in your life may help.

Be Aware of Environmental Toxins

Environmental toxins can have an impact on fertility. “Be aware of any environmental toxins that you are exposed to at work that could impact fertility: heavy metals, pesticides,” says Dr. Sun.

One study found that heavy metals can alter reproductive function in both women and men, potentially leading to a decrease in sperm count and motility, causing hormone imbalance and more[5]. So if you know or suspect you’re being exposed to heavy metals or other pesticides, do your best to eliminate them as much as possible. Other studies have found that BPA and phthalates may harm fertility in both men and women[6].

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Fertility Testing and Treatment

If you’re dealing with fertility issues, one of the very best things you can do is talk to a fertility specialist or an OB-GYN who can make a referral for you. There are specific tests that can be done to better understand your fertility.

“If you’re having difficulty getting pregnant, it’s good to know that your doctor has a number of tests to clarify what the challenges are for you and there are treatments that can improve your chances,” says Dr. Roskin. “Fertility testing generally tries to focus on the system that may not be functioning as it should.” For example, a hormone imbalance that prevents normal ovulation, or a blockage in the fallopian tube that prevents fertilization.

“Once the issue is better defined, treatments can be planned such as hormonal medications to regulate or stimulate ovulation, surgery to address tubal blockage or in vitro fertilization (IVF),” says Dr. Roskin.

When to See a Doctor About Fertility

You should always feel comfortable talking to a doctor about any fertility issues you’re experiencing. “I always advise patients to see a doctor when they are in the stages of preparing for pregnancy, or when they are contemplating pregnancy, for a preconception consultation,” says Dr. Sun. “Preconception visits allow us to work together to optimize your health to mitigate some of the factors that may contribute to infertility.”

You should also consider seeing a doctor if you’ve been trying to get pregnant for a year or more without success. “In general, if you are under age 35 and have been trying for a year without birth control and haven’t conceived, you should have an infertility evaluation,” says Dr. Roskin. “If you are 35 or older, you should see your doctor after six months of trying. If you are 40 or over, you should talk with your doctor right away about an evaluation.”




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