Hormones. More often than not, they're an absolute bitch for us women to deal with.
And we understand you guys (including my dear husband) probably want to knock us out cold when they turn us into intolerable monsters, such as when we get our premenstrual mood swings.
But on the flip side, these are the same chemicals that make us want to get hot and sweaty under the covers with you.
So to help you men better understand what we're really feeling when we're hit by these hormones, here's a five-minute survival guide that you'll find handy.
It'll tell you what you should do, what you shouldn't do - and how to score extra brownie points (you know what I mean).
1. WHEN WE'RE HORNY
One "happier" result of hormones is that it makes us horny. Very horny, actually. But, unfortunately, when this actually happens differs from woman to woman.
Some feel it when they're ovulating, which is approximately around Day 14 of their menstrual cycle; others turn into absolute horn dogs just before they get their period.
This is the best time for you, good man, to satisfy your woman. It won't last long, so take advantage of it!
2. PREMENSTRUAL SYNDROME
Before we get our periods, we go through a few days - perhaps even a week - when we feel irritable, sad, angry, weepy, frustrated… (insert some other negative emotions here).
This is known as premenstrual syndrome. And as much as you want to believe otherwise, we have absolutely no control over it.
On top of our mood swings, we also have physical symptoms such as headaches, backaches and breast tenderness, which explains why we often want to slap you when you try to touch us.
We don't mean to be cold but, at this time, we really would like you to get out of our way. Really. And what you shouldn't do is ask: "Why are you such a grumpy bitch?"
And if you're looking to score brownie points, most of us have a massive chocolate craving while we're PMS-ing. So, please make sure we're constantly surrounded by chocolates, thank you very much.
Yes, the dreaded five to seven days of the month when women curse every man on Earth and wish we were born male. And just so you know, it's different from PMS.
While the mood swings during PMS might have subsided, the agony for us now consists of cramps, body aches and general blah-ness.
Be nice to us. Because you don't want to find out exactly how good we are with knives.
Extra points for the man who can offer us heat pads and massages, and light our favourite scented candles while we put up our feet.
If you find PMS a monthly battle you can't win, then pregnancy is like stepping into an active war zone without any weapons.
If you're not prepared for how to deal with all the changes that come with pregnancy, you're either very brave… or very stupid.
Mood swings are more common in the first and last trimesters, so consider yourself lucky that it lasts only six of the nine months.
Even if the pregnancy was planned, many women go through a range of feelings of uncertainty as to whether they're ready for it and what kind of mothers they'll be.
So be prepared to deal with this and constantly reassure her. Besides, you had something to do with getting her into this situation - so do be involved all the way, too. It might even be less work than when the baby is actually born.
Guys, take note: If she wakes up at 3am craving for char kway teow and you have to drive half an hour to get to the nearest 24- hour stall, do it anyway.
She is, after all, carrying your child.
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