why do doctors always ask when my last period was?

Among other changes, blood flow to the heart varies during the menstrual cycle. There are many organs that produce hormones (endocrine system) during this time and this affects elevated stress levels, weight gain, weakness in bones and loss of energy. It also can affect the rate of healing of an injury.

Any medication that you are already on or that the doctor prescribes must be considered and balanced from the perspective of the hormonal changes.

All parts of the human body interact and the menstrual cycle has strong effects. If you don't remember the dates or don't wish to discuss it with the doctor, just tell him that. There is no law requiring you to disclose that information.

I can personally understand exactly why you feel that way, because it can indeed be very annoying and sometimes highly embarrassing. I know precisely what it's like, because a neurologist I once met asked me that right in front of my mum, maternal aunt and 2 boys who I went to school with. (The boys were there at the time because they saw what happened when I had a seizure due to my epilepsy).

However, they don't ask just for the fun of it. It's because they genuinely do need to know, since there are multiple health problems which can be linked to the menstrual cycle, such as anemia, stress, epilepsy and acne.

Hope this helps.

Because your period schedule might be related to health problems

Such as missing it for long periods of time

Keeping track of your cycle is helpful not only to a doctor but for you as well. Be a woman and keep track of your menses for your health and knowledge. A period occurs every 28 days. Knowing the times can help you in case your menses become irregular, painful, absent or continuous. I had a mense cycle that lasted 100 days. I thought I was dieing. Turns out I had endometriosis. My uterus was a solid mass. I wasn't having actual cycles since my uterus wasn't functional.

There are indicators of certain diseases that can be attributed to many irregular periods and doctors would like to catch them early if they can.

Just to make sure everything is in check.

My doctor would ask when my last period was and how long did it last.

while I agree, it's a silly question to ask for a knee treatment.......

it's also not a terribly difficult question to answer in round about vague terms.

I don't think they want hour and minutes........ a simple "two weeks ago" should suffice .

and technically, they could be asking for swelling or bloated issues, to rule that out.

Certain health issues can affect your period, not just being pregnant. Extreme exercise, being low in certain nutrients, extreme stress, certain illnesses, and eating disorders can cause you to miss a period. All of these things, obviously, can take a toll on other areas of your health. So the period can act as an indicator if your body is in distress.

tell them it is your business, not theirs.

Just give a guesstimate... it's a routine question.