Key factors affecting fertility and how they influence ovulation

Nothing in this article is or should be construed as medical advice; for any medical questions, consult your healthcare professional.

The test is negative. Again. It’s been quite a few months now since you decided to try to get pregnant. Well-meaning people tell you it takes time. Not to stress. That it’s common. (And it is common — nearly 15% of couples worldwide have difficulty getting pregnant.¹) But still you wonder: Why am I not pregnant yet? Could there be an underlying problem affecting my fertility and ovulation?

What are common factors affecting fertility?

Various health conditions and lifestyle habits can affect ovulation and fertility, and treatment is dependent on a diagnosis. The most common physical or lifestyle factors affecting fertility include age, weight and whether or not you consume alcohol or smoke.²

All people — including men, women and nonbinary/transgender individuals — can experience difficulties with fertility, and in some cases the cause is unknown. Infertility isn’t solely a female issue: about one-third of cases are attributed to female factors, one-third to male factors, and one-third involve both partners or remain unexplained.

Female infertility can be difficult to diagnose and sometimes requires seeing a reproductive endocrinologist.³ According to the American College of Obstetricians and Gynecologists (ACOG), the most common cause of female infertility is a problem with ovulation.³

Why am I not ovulating?

Ovulation timing can vary from cycle to cycle, and occasional irregularity doesn’t always signal a long-term fertility issue — but persistent changes are worth discussing with a healthcare provider. 

Here are some of the most common factors affecting ovulation:

• Age³
• Stress²
• Weight changes³
• Hormonal imbalance²
• Medications²
• Medical conditions (We’ll dig into these more below.)

If you suspect an ovulation issue could be the cause of your difficulties with conceiving, talk to your ob-gyn. Consulting a doctor is crucial to narrow down any potential problem(s) and pursue treatment accordingly. In the meantime, understanding your menstrual cycle and boosting your fertility health with lifestyle changes like exercise, diet or reducing alcohol and tobacco use can help.

When to talk to your doctor about fertility testing

ACOG recommends an infertility evaluation if you’ve been having regular sex without birth control for one year and have not yet gotten pregnant.³ If you’re older than 35, that evaluation should happen after six months of trying. If you’re older than 40, you should talk to your ob-gyn before trying to get pregnant.³

Your healthcare professional can also help determine whether there may be other underlying conditions contributing to your fertility troubles. Testing may include hormone blood tests, ultrasound imaging, ovulation tracking, or other evaluations based on your health history and symptoms.⁴ Even if a specific cause isn't identified, many people successfully conceive with the right treatment approach.⁵ Your provider can guide you through the options that make sense for your age and situation.

Health conditions that can affect a woman’s fertility

1. Endometriosis 

ACOG says endometriosis is a sometimes quite painful condition that occurs when the tissue that lines the uterus grows outside the uterus.⁶ Symptoms include chronic pelvic pain near or during your menstrual period, heavy menstrual bleeding and sometimes pain during bowel movements and/or urination. You may not have any symptoms at all.⁶ ACOG says almost four in 10 women experience endometriosis and fertility issues.⁶ Inflammation caused by endometriosis can damage the egg or sperm, interfere with their movement or cause blockages in the fallopian tubes (which is where the egg and the sperm meet) due to adhesions or scarring.⁶

2. Hypothyroidism and hyperthyroidism

If you have hypothyroidism with fertility issues, you have an underactive thyroid and your body doesn’t make enough thyroid hormones, possibly causing anovulation, irregular or heavy menstrual bleeding. If you have hyperthyroidism with fertility issues, you have an overactive thyroid and your body makes more thyroid hormone than it needs, possibly causing anovulation, lighter/shorter or missed periods. Some studies have linked abnormalities in thyroid function with reduced rates of conception.⁷

3. Pelvic inflammatory disease (PID)

According to ACOG, more than 1 million U.S. women are diagnosed with PID each year.⁸ Symptoms, which may or may not be present, include pain in the lower abdomen and/or upper right abdomen, abnormal vaginal discharge and/or menstrual bleeding, painful urination and/or sex, nausea and vomiting, and fever and chills. While some cases of PID are caused by non-sexually transmitted infections, most are caused by two STIs — gonorrhea and chlamydia. It’s estimated one in 10 women with PID will become infertile due to fallopian tube scarring.⁸

4. Polycystic ovarian syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is now being referred to by a new name: Polyendocrine Metabolic Ovarian Syndrome (PMOS). It’s not uncommon for women struggling to get pregnant to find out they have PMOS, a hormonal imbalance that affects the ovaries — and fertility. According to ACOG, symptoms can include irregular menstrual periods, obesity, excess hair growth, severe acne, changes in skin texture (oily or thick patches of darkened skin) and/or multiple fluid-filled sacs in the ovaries.⁹ The Office of Women’s Health, U.S. Department of Health & Human Services (OASH) says polycystic ovary syndrome and infertility affects as many as one in 10 women of childbearing age.¹⁰ While there’s no cure for PMOS, your ob-gyn can suggest treatments that can help you ovulate, ranging from losing weight or taking medicine to in vitro fertilization (IVF) or surgery.¹⁰

If you suspect one of these conditions — or another factor — may be affecting your fertility, talking with a healthcare provider can help bring clarity. Advances in fertility testing and treatment mean there are more options than ever, and many causes of ovulation challenges are manageable with the right support.

Understanding how fertility works is a powerful first step. Whether you’re just beginning to ask questions or ready to pursue testing, having information can help you make confident, informed decisions about what comes next.

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