Can You Be Pregnant and Not Know It?

We’d all like to think we have a solid grip on “that time of the month” and how our reproductive system works. The arrival of a monthly period is confirmation that you’re not pregnant and things seem to be business as usual.

Still, it seems like every so often we hear or read about a woman not knowing she was pregnant and unexpectantly giving birth to a surprise baby.

We all gasp in wonder. How in the world is that even possible?

But according to Ob/Gyn Rebecca Russell, MD, it’s not entirely uncommon if the circumstances allow it.

If you’re still skeptical, here are seven reasons why a woman might not realize she’s pregnant:

1. Irregular periods. About 30% of women have irregular periods — meaning it doesn’t fall between the 21 to 35 day time frame. In this case, a late period might seem like no big deal to some. Other women only have a few periods a year, so going for months without one would raise no flag or concern over a possible pregnancy.
2. Intermittent spotting. Some women may have occasional spotting throughout pregnancy, which could be mistaken for a light period.
3. No symptoms or signs of pregnancy. Some women don’t know they’re pregnant simply because they don’t have any symptoms. No low back pain, no pelvic cramping and no nausea — they feel completely fine and like their typical selves.
4. No pronounced “bump.” It’s no secret that obesity is an epidemic in the United States. And although a baby bump is typically much firmer than the rest of the belly, for someone with a cryptic pregnancy, obesity and being overweight can camouflage it.
5. Age and past infertility. Women in their late 30s or early 40s could mistake pregnancy symptoms with early menopause. They might also think that their chances of conceiving are lower because of age. Or perhaps they’ve been diagnosed with polycystic ovary disorder (PCOS) or infertility in the past and don’t believe they could actually be pregnant now.
6. Denial. Some women don’t want to acknowledge a pregnancy because of fear or shame. Maybe they chalk it up to a stomachache or that they haven’t been exercising and that’s why they’re gaining weight. It’s too stressful to acknowledge it, so they don’t.
7. Still on birth control. One of the main reasons women tend to come in late is because they’re still taking birth control pills. If they frequently skip the period week and are only having a couple periods a year, they might not think much about it.

So how do you avoid a surprise baby?

If you’ve decided that having a baby isn’t for you, or that you’d like to have more notice for when you’re actually expecting — it’s important to be aware of your cycle, your body and how sexually active you are.

“Any women who could get pregnant should be on a multivitamin with folic acid,” says Dr. Russell. “Folic acid greatly reduces the chance of birth defects. It’s one of the most important things you can do if there’s a chance of becoming pregnant.”

It’s also recommended to track your cycle, either with an app or jotting it down on a calendar. Having a pulse of when you menstruate and ovulate could better protect you from an unplanned pregnancy.

“If you start noticing any unusual symptoms, even if you’re on birth control, take a pregnancy test,” says Dr. Russell. “And if that comes back negative and you’re still suspicious in two weeks, take another one.”

It’s also important to remember that having sex — even just one time — could result in pregnancy. Even if you’re having sex rarely and infrequently, pregnancy can still happen.