Breast Cancer Screening at 40 in Ontario: How to Self-Refer and What to Expect

Can You Get a Mammogram at 40 in Ontario? Yes, and You Can Book It Yourself

Since October 2024, the Ontario Breast Screening Program (OBSP) has included people aged 40 to 74 who are at average risk of breast cancer. You don't need a requisition from a provider. You can self-refer by calling an OBSP screening site directly or by using Ontario Health's online tool to find a site near you. Bring your valid Ontario health card. The screening mammogram itself is covered by OHIP when it's done through the program.

Most people in the program are screened every two years. Some are recalled every year instead, usually because of dense breast tissue or a family history of breast cancer. The site will tell you which schedule applies to you in your results letter.

Who Can Self-Refer for a Mammogram in Ontario

Self-referral is designed for people who don't have symptoms and aren't already known to be at higher risk. Generally, that means you're between 40 and 74, you have no current breast symptoms, you have no personal history of breast cancer, and you haven't had a screening mammogram in roughly the past year. Trans women who have taken feminizing hormones for five years or more, and trans men or nonbinary people who haven't had chest surgery, may also be eligible. If you have breast implants or have had breast surgery, check with your provider or the screening site first, since the booking process can be different.

If you're pregnant or breastfeeding, talk to your provider before booking. Routine screening is often timed around these stages, and your provider can help you plan the right moment.

Booking a Self-Referred Mammogram in Toronto

Toronto has a mix of hospital-based and community OBSP sites, and wait times vary from one to the next. It's reasonable to call two or three sites and compare. When you book, the site will ask whether you have a family doctor or Nurse Practitioner. Naming your provider matters more than it seems, because it determines who receives a copy of your results.

What to Expect at Your First Mammogram

The appointment itself is short. Most take about 20 minutes, and the actual imaging only a few minutes of that. A technologist positions each breast on a plate and gently compresses it for a few seconds while the image is taken. It can feel uncomfortable, and some people find it briefly painful, but the pressure lets the machine get a clearer picture with a lower dose of radiation.

A few small steps can make the day easier. Skip deodorant, powder, and lotion on your underarms and chest that morning, since they can show up on the image. Wear a two-piece outfit so you only need to remove your top. If your breasts tend to be tender before your period, try booking for the week after it ends.

Your results usually arrive by mail within a few weeks. A copy goes to your provider if you named one. If you didn't, you're left to interpret the letter on your own, which is where many people start to feel uncertain.

Dense Breasts in Ontario: What Your Results Letter Means

Ontario now reports breast density in OBSP results letters. Density describes how much of your breast is made of fibrous and glandular tissue compared with fatty tissue. It's rated in four categories, from A (mostly fatty) to D (extremely dense). Dense breasts are very common, especially in your 40s, and having them isn't a sign that anything is wrong.

Density matters for two reasons. Dense tissue can make a mammogram harder to read, because both dense tissue and some tumours appear white on the image. It's also linked to a modestly higher risk of breast cancer. If your letter says category D, the program will generally recall you every year rather than every two. For categories C and D, it's worth asking your provider whether supplemental imaging, such as breast ultrasound, makes sense for you. That decision depends on your overall risk, so it's a conversation rather than an automatic add-on.

Density often decreases after menopause, and hormone therapy can affect it. If you're weighing treatment for hot flashes or sleep changes, our menopause care appointments include a discussion of how that choice fits with your breast screening plan.

What Happens After an Abnormal Mammogram

Being called back after a screening mammogram is stressful, but it's also common. A recall usually means the radiologist wants a closer look at an area that's hard to interpret. The large majority of people who are called back don't have cancer. First-time screeners in their 40s are recalled more often, partly because there are no earlier images to compare against.

Follow-up typically starts with a diagnostic mammogram, which uses extra views of the specific area, and often a breast ultrasound. If something still needs clarifying, the next step may be a biopsy, where a small tissue sample is taken with a needle. This work is often done through a breast assessment centre, which coordinates imaging and biopsy so you're not booking each test separately.

The part that tends to break down is follow-through. Without a provider, you may not know who is tracking your appointments or who will explain a biopsy report. At Care&, your NP can review the recall with you, make sure each test is booked, and sit down with you when results come back. You shouldn't have to piece it together alone.

If You Might Be at Higher Risk

Some people shouldn't rely on average-risk screening at all. If you have a known BRCA1 or BRCA2 gene change, a strong family history of breast or ovarian cancer, or chest radiation before age 30, you may qualify for the OBSP High Risk program. It offers yearly mammograms and breast MRI for eligible people aged 30 to 69. Unlike regular screening, it requires a referral and sometimes a genetic assessment first, so your provider needs to start that process with you.

Breast screening is also a good prompt to check the rest of your preventive care. Many women in their 40s are overdue for other tests, and our guide to Pap tests, HPV screening, and cervical health for Toronto women explains where you might stand. Once you're approaching 50, colorectal cancer screening in Ontario becomes part of the picture too.

When to See Your Nurse Practitioner

You can book an OBSP mammogram without any provider involvement. But it's worth seeing someone if you're unsure about your family history, your letter mentions dense breasts, you've been called back, or you've noticed any change in your breasts. OHIP-covered family practices remain a good option if you have one and can get an appointment when you need it. Many Torontonians don't, though. Care& offers a membership that's not covered by OHIP, with unhurried appointments and the same NP each visit, so your screening history doesn't get lost between providers. Our women's health services in Toronto cover breast screening follow-up alongside the rest of your care.

Frequently Asked Questions