You can still get pregnant at 46

What is the first sign that perimenopause has started? Most women guess hot flashes. Today's three verdicts say the transition is stranger, and slower, than that.

TODAY'S TOPIC: Women's Reproductive Health and the Menopause Transition

"Perimenopause always begins with hot flashes."

Hot flashes get all the attention, so it makes sense that women expect them first. For a large share of women, they are not the opening act.

Sleep disruption, mood shifts, and changes in period length or flow often arrive years before a single hot flash does. Estrogen and progesterone start fluctuating unevenly long before they drop enough to trigger vasomotor symptoms like flushing.

Research tracking women through the transition finds wide variation in symptom order. Some women go through the entire process without a noticeable hot flash at all.

If your first sign was a shorter cycle or a worse night's sleep, that still counts.

"You can get pregnant during perimenopause, even with irregular periods."

This one surprises women who assume irregular cycles mean the reproductive system has already shut down. It has not, not yet.

Ovulation becomes unpredictable during perimenopause, but it does not stop on a schedule. A woman can skip several cycles and then ovulate without warning.

Well-established data shows unintended pregnancy rates rise in women over 40, in part because contraception gets dropped too early. Doctors generally recommend continuing birth control until a full 12 months have passed without a period.

Irregular is not the same as over.

"Menopause is a single day you can pinpoint on a calendar."

Menopause does get assigned a specific date, technically. That date only makes sense looking backward.

Clinically, menopause is defined as the point 12 months after your final period. You cannot know you have reached it until a full year has already passed with no bleeding.

That means the day itself is invisible while it is happening. You only find out you crossed the line once you are already well past it.

So yes, there is a date. No, you will not know it in the moment.

The transition does not follow a script, and it does not announce itself the way you were told it would.