The Science Behind Menstrual Cramps: Understanding the Role of Prostaglandins

[Mr. Robin Parsons]

One_raven,
I hope you don't rely on the rhythm method for birth control! Menstruation is one of the least likely times for a woman to get pregnant. I think if there is any good reason why some women get a little pissy (mind you, I said some because not all do), it would be because they are experiencing pain and discomfort. No one likes pain - you'd be irritable too.

Heck, I'm a guy, and I agree with that!

 

[Monique]

One_raven,
I think if there is any good reason why some women get a little pissy (mind you, I said some because not all do), it would be because they are experiencing pain and discomfort. No one likes pain - you'd be irritable too.

That too, but many women suffer from PMS, prémenstrual syndrome, where in fact hormonal imbalances cause the irritabel/emotional state of mind.

 

[one_raven]

That too, but many women suffer from PMS, prémenstrual syndrome, where in fact hormonal imbalances cause the irritabel/emotional state of mind.

Exactly.
I thought it's called PMS because it happens before menstruation.

 

[Moonbear]

Exactly.
I thought it's called PMS because it happens before menstruation.

Yes, it begins before menstruation in many women, but can continue throughout the period of menstruation. The physical symptoms can begin a few days before the onset of menstruation as well. The increase in prostaglandins and decrease in circulating steroids begins several days before menstruation. Many women experience not only abdominal discomfort, but also back pain and headaches, in addition to the effects on mood.

There is also a more severe form called premenstrual dysphoric disorder (PMDD) . PMDD is currently treated with SSRI's (I'm not sure if this is an approved therapy or still in clinical trials, but I've seen many reports in the literature on it), so may reflect a mild underlying disposition to depression that increases in severity when hormone concentrations drop. PMDD is considered a bona fide psychiatric disorder and is treated as such.

 

[one_raven]

So...
Since PMS starts a few days before ovulation... during PMS, women are quite likely to get pregnant, right?

 

[Jenn_ucsb]

So...
Since PMS starts a few days before ovulation... during PMS, women are quite likely to get pregnant, right?

Oh lordy, dear one_raven, PMS stands for premenstrual syndrome. It precedes menstruation, not ovulation. They are different things. Please go read up on this. Here's a good visual summary for the scientifically inclined:
http://www.people.virginia.edu/~rjh9u/menscyc3.html

And please, no sex until you understand this.

 

[one_raven]

Really?!
Its s good thing I use condoms!

 

[one_raven]

I always thought it went something like this:

Day 1 (start of PMS): Egg drops down to the Uterus. Woman can get pregnant.
Day 4 or 5: If the egg was not fertilized, menstruation starts and the egg is washed from the system with blood.
Day 8 or 9: Egg is gone, 20 more safe days to go.

Go figger.

 

[adrenaline]

Day 1 (start of PMS): Egg drops down to the Uterus. Woman can get pregnant.
Day 4 or 5: If the egg was not fertilized, menstruation starts and the egg is washed from the system with blood.
Day 8 or 9: Egg is gone, 20 more safe days to go.

Assuming a 28 day cycle, ovulation usually occurs around 2 weeks before menstruation, as someone has already reiterated. PMS usually starts during the week of the very rapid decline of both estradiol and progesterone which is usually the 7 days before menstruation and may continue througout the menstruation. The egg can be fertilized anywhere between the time it enters the fallopian tubes and the uterus , most of the time it is already fertilised and dividing by the time it is deposited in the uterus.

 

[Moonbear]

One_Raven, please please please read carefully what Adrenaline just posted and what I have posted up closer to the top of the page here about the timing of the menstrual cycle. Ovulation occurs about 14 days AFTER the start of menstruation (or before...it's a cycle, so depends on which way you want to think about it).

If you don't mind sharing, can you please tell me where you learned about reproduction? This is not the first time I've heard someone have it completely backward about when ovulation is relative to menstruation, so I'm wondering if this is something that needs improving in how it's presented in schools. The reason I ask is that my primary area of research is on the reproductive system, and I belong to a professional society that promotes education and outreach on reproductive issues. I always thought these basics were covered in most schools nowadays, so I'm wondering where the confusion begins and how to address it. Is it that kids just aren't listening in class, or that it's being taught wrong or in a confusing manner, or are there schools where this still isn't being taught at all and kids are still getting the same wrong information repeated by their parents or peers? The last person I spoke with who had the same misinformation you did had attended a Catholic school quite a while ago, when Catholic schools pretty much avoided any discussion at all of reproductive biology and left that up to parents. Clearly that didn't work very well.

 

[one_raven]

I went to public school in New Jersey.
We did have sex-ed (or health class, as they called it) but the information was not covered very well, and was presented in a pretty rough and confusing manner.
So, the blanks were filled in by what other confused people told me.
The way they explained it made sense.
There were days that the boys ang girls were separated (I assume to avoid embarrassment) to discuss the "boy stuff" with the boys and the "girl stuff" with the girls, and I imagine they covered menstruation with the girls in more detail on those days.

You have to remember, though, this was about 20 years ago.
I was one of the first classes to get sex-ed in my town.
I don't know how it is now.

 

[Moonbear]

Hey, cool, I grew up in NJ too! Probably going through the schools at about the same time...though in our school system, we had sex ed (yes, also called health class then) EVERY year from about 5th grade through senior year. The only year we didn't have sex ed in health class was the year it was replaced with driver's ed. We started getting sick and tired of the same stuff every year, but it sure made for an easy A after a while. I didn't realize there was so much variation even in the same state. I thought the curriculum was fairly standardized across the state educational system. Of course we had the advantage in my school that the health teacher was a former OB nurse, so she really knew her stuff. We also only separated boys and girls the first year (fifth grade), when they basically were explaining what to expect as puberty began. After that, all sex ed was with both sexes present. That makes more sense to me than separating the sexes since everyone needs the same information.

Anyway, thanks for sharing that. I wonder if things have improved since then. I hope so. I think it's important to start with the basics and gradually build upon that. It's good to teach anatomy, but I think too many schools focus entirely on the reproductive anatomy and leave out the important things like when ovulation actually happens and how long sperm can live. It's probably an attempt at avoiding giving kids the illusion there are "safe" times of the cycle when teenage girls especially can have incredibly variable cycle lengths.

 

[one_raven]

Hey, cool, I grew up in NJ too!

If it's not too personal, where in NJ, and how old are you?

 

[Moonbear]

If it's not too personal, where in NJ, and how old are you?

Well, since it wasn't exactly a small town, it's not like you or any other potential internet wackos are going to track me down based on where I grew up. I'm originally from East Brunswick.

But a lady never divuldges her age Hee hee...how about I stick with somewhere in my 30s.

Your turn. If it turns out we were potential neighbors or something, we should take this discussion off the board since I don't think catching up on old-times in NJ is exactly the focus of the biology topic (I think this site came with some way to set up a free email account with membership...I'll look into that).

 

[Monique]

Besides the email account, you are able to send private messages (PMs) to other members. Click on the profile to find a link, or look at the top of the page to the right :)

 

[The_Professional]

In my country, I went to a private Catholic school for boys and we had sex education taught by priests. YIKES!

 

[Kerrie]

So...
Since PMS starts a few days before ovulation... during PMS, women are quite likely to get pregnant, right?

ovulation occurs approx 2 weeks prior to mentruation, during the two weeks after ovulation ( I think ) the egg comes down the fallopian tubes into the uterus...

 

[Kerrie]

I think they should if menstrual cramps can already be that bad, I am afraid what the labour cramps are going to feel like

that depends on your tolerance of pain...i have had to vaginal births of my children, the first i had an epideral, the second i had nothing for pain. with the epidural, i was unable to walk, had to remain in bed with a catheter (which is the most uncomfortable thing ever), remained in labor for 19 hours and when it came time to deliver i had no idea what to do because i couldn't feel a thing. when i had my second child, labor was only 4 hours (mostly due to it being my second) and when it came to time to deliver, i knew when to push because the contractions were being felt...yes, it hurt, but you forget that pain once the 30 minutes is over and you are holding your child that you had been carrying for 9 months. i have heard that active women can tolerate pain more because their endorphins kick in faster, not sure how accurate this is.

 

[Evo]

that depends on your tolerance of pain...

Very true, but there can also be other factors. My mother felt no pain and had 4 children. She didn't even know she was in labor with my little sister. She told me that labor pains were a "little twitch". This is a woman that is flat on her back if she has even a little headache, so I figured I would have no problem with labor pain.
WRONG!

My first labor was 42 hours of the most excrutiating pain I can imagine the human body enduring. Imagine having the entire inside of your body being slowly ripped inside out. I had several epidurals, THANK GOD for EPIDURALS! It was the only relief I had. Kerry, it sounds like you went into labor too soon after the epidural was administered, usually the epidural is allowed to wear off prior to delivery time. My daughter never turned and was born face up. Her back was pressed against my spine the entire time. My upper left leg had no feeling for 6 months after she was born. The GOOD news is, that thanks to the epidural, I was strong enough at delivery to push her out on the third push. The doctor was amazed. I would not have been able to without the epidural allowing me to rest.

And I have NEVER forgotten the pain. My heart is racing right now even writing about it.

I did have a second child, less than 32 hours in labor. A lot less painful, but I did have epidurals. It took me 6 pushes to get her out 9LBS 6 OZ. A little heffer.

BTW, I have very painful menstrual cramps normally.

 

[Monique]

that depends on your tolerance of pain...

I guess it would depend more on the kind of pain.. your stories are impressive though :)

 

[one_raven]

Your turn. If it turns out we were potential neighbors or something, we should take this discussion off the board since I don't think catching up on old-times in NJ is exactly the focus of the biology topic

Not exactly neighbors.
I grew up in Clifton and Elmwood Park.
Little more than an hour north of you.
10 minutes West of NYC.

I'm 32, by the way.

 

[Njorl]

A word of advice to you guys out there. Do not attempt to alleviate your wife's labor pains with "a little humor". If my wife had a gun, she would have shot me. I don't remember what I said, but I swear when she turned her head and glared at me I heard the pump action of a shotgun.

She had a painful time of it. The damn anaestesiologist missed with the epidural. They refused to give her another one for fear of overmedicating her. When they finally did give her another, it kicked in right before delivery, and she had a real hard time pushing.

Njorl

 

[Moonbear]

Njorl, it really depends on your wife. Then again, maybe it was just a bad joke :-) When my sister was in labor, we were joking quite a bit...actually, I think my brother-in-law said something stupid (not uncommon with him) and she looked at him and asked, definitely joking, "Is this when I'm supposed to say we're never having sex again?"

There have actually been recent studies that it's better to not get an epidural. Epidurals can slow the contractions and extend the time of labor. There have also been reports of more vaginal tearing during delivery in women with epidurals. There's a slower recovery afterward, including more problems with lower back pain and numbness in the legs. There are also reports that it can leave the baby more lethargic upon delivery too so they don't nurse as well in that first feeding right after delivery.

Of the women I've known who have gone through labor without epidurals, either by choice or because there was a reason they couldn't get it (too far progressed by the time they got to the hospital, some contraindication, etc), they've all seemed to have very short labors (hard labor was only about an hour and a half...that's the part that really hurts...the rest they said hurt, but was tolerable), and within hours of delivery already seem to forget the severity of it. The main thing that they all say makes it tolerable is knowing it will be over. Usually their husband's recollection is far better than their own.

Of those who had epidurals, their labor was so much longer...to the point where many of them have wound up getting oxytocin (something they'd never wish on their enemies they tell me...oxytocin injection induces far stronger contractions than normal labor, and apparently far more painful...those women all still remember that pain). One even had to have the epidural stopped because it slowed labor so much...once it was stopped, labor progressed normally.

Anyway, that's all anecdotal, but it's been such a consistent pattern among my friends and relatives that I certainly plan to go for a drug-free delivery when it's my turn.

 

[adrenaline]

I was in labor 24 hours, probably because I had worked a 15 hour shift just beforehand. I could not get an epidural since I was on Lovenox (low molecular weight heparin) for Factor V Leyden disease (my twin already had a huge pulmonary embolism). No sedation. I thought I was tough since I have broken major bones and kept racing during some of my mountain bike races ( finished a race with a posterior dislocated shoulder and another with a radial head fracture) so I thought I was tough cookie and everyone else were just being pansies... But the pain was excrutiating! I yelled at my husband and told him he was counting all wrong. Then,as Chief of Medicine I ordered my OB to give me a damn epidural anyway and I would not sue him if I had a spinal bleed and got paralyzed. He just laughed and told me I was not of right mind and he only took his orders from the Chief of Surgery. I think I threw a kidney basin at him. Anyway,the point is, I thought I could anticipate the pain but boy was I wrong!

 

[Evo]

There have actually been recent studies that it's better to not get an epidural. Epidurals can slow the contractions and extend the time of labor. There have also been reports of more vaginal tearing during delivery in women with epidurals. There's a slower recovery afterward, including more problems with lower back pain and numbness in the legs. There are also reports that it can leave the baby more lethargic upon delivery too so they don't nurse as well in that first feeding right after delivery

Of the women I've known who have gone through labor without epidurals, either by choice or because there was a reason they couldn't get it (too far progressed by the time they got to the hospital, some contraindication, etc), they've all seemed to have very short labors (hard labor was only about an hour and a half...that's the part that really hurts...the rest they said hurt, but was tolerable), and within hours of delivery already seem to forget the severity of it. The main thing that they all say makes it tolerable is knowing it will be over. Usually their husband's recollection is far better than their own.

Of those who had epidurals, their labor was so much longer...to the point where many of them have wound up getting oxytocin (something they'd never wish on their enemies they tell me...oxytocin injection induces far stronger contractions than normal labor, and apparently far more painful...those women all still remember that pain). One even had to have the epidural stopped because it slowed labor so much...once it was stopped, labor progressed normally.

Anyway, that's all anecdotal, but it's been such a consistent pattern among my friends and relatives that I certainly plan to go for a drug-free delivery when it's my turn.

I agree a lot of women have easy labor and don't need an epidural. Why they do not understand some women aren't as lucky really makes me angry. I would compare their labor to a paper cut and I was undergoing major surgery.

My contractions started before the baby dropped, I wasn't dilating, I was bleeding so heavily the blood was dripping off the side of the hospital bed, the nurses couldn't replace the pads under me fast enough.

The women that didn't have epidruals and said "oh' it's not that bad, & I don't remember the pain, blah, blah, blah", are like my mother, she didn't experience pain. My girlfriend had very moderate pain & a quick delivery. I know women that had just the opposite, like me. The women you are talking about are lucky, they don't know how severe the pain can be.

I did notice that the women that didn't have epidurals had much more trouble pushing than I did. They were so exhausted after even a few hours of labor that they didn't have the strength to push properly. Thanks to the epidural, I was able to rest, and I had no trouble pushing.

Moonbear, I hope for your sake you're one of the lucky ones that has a fast, relatively painless delivery.

Adrenaline, I know what you went through. I'm surprised you didn't harm anyone.

 

[Kerrie]

during the birth of my second with no pain killers, i screamed, i yelled at my husband because it hurt very bad...i was lucky that i only had a 4 hour labor and delivery, but once you see your child, it makes it easy to forget.

 

[hitssquad]

Oxytocin, calorie restriction, and child delivery

Of those who had epidurals, their labor was so much longer...to the point where many of them have wound up getting oxytocin (something they'd never wish on their enemies they tell me...oxytocin injection induces far stronger contractions than normal labor, and apparently far more painful

Interestingly, oxytocin is a "feel-good" hormone released in females http://milepost1.com/cgi-bin/wa?A2=ind0404&L=crsociety&P=37771 :

• I've hypothesized in the past that CR lowers the male sex drive and
  raises the female one. The male drive is a no brainer as CR lowers the
  male hormone, testosterone.
  
  But, what about the female drive?
  
  http://www.13.waisays.com/clitoral.htm discusses this. The female orgasm
  results in the release of the feel good hormone oxytocin. Oxytocin is an
  appetite suppressant so regular good sex helps women stay on CR.
  
  The site discusses the effects of food on oxytocin. Due to lowering
  oxytocin the site states "Therefore, consuming wheat- and dairy products
  and consuming prepared proteinous food (prepared meat, -fish, -soy,
  -beans) can decrease your sex life, by inhibiting libido." The flip side
  of this is a diet low in wheat, dairy and prepared foods leads to more
  oxytocin. Seems a typical CR diet to me - for both sexes!
  
  Male Cronies do not miss the lovemaking boat at all. Men have oxytocin
  too and lower testosterone and a CR diet makes oxytocin more effective
  in men.

Might child delivery be easier in females practicing calorie restriction?

 

[Monique]

Interestingly, oxytocin is a "feel-good" hormone released in females http://milepost1.com/cgi-bin/wa?A2=ind0404&L=crsociety&P=37771 orgasm.

Infact oxytocin is a muscle contractor, explaining the involvement in orgasm, labor, and also lactation.

Apparently it is also involved in calming and positive social behaviour (if oxytocin is blocked during birth, a ewe was shown to reject her lamb [Barry Keverne, Keith Kendrick, and their colleagues at the University of Cambridge]).

That would make sense too. In fact when a mother is nursing she feels very calm and more tired, I think this is the effect of oxytocin, you wouldn't want a mom to be running around while nursing. But when injected at high concentrations during labor it acts as a strong muscle contractor, giving cramps, and no one likes those.

 

[Kerrie]

That would make sense too. In fact when a mother is nursing she feels very calm and more tired, I think this is the effect of oxytocin, you wouldn't want a mom to be running around while nursing. But when injected at high concentrations during labor it acts as a strong muscle contractor, giving cramps, and no one likes those.

that's the truth! i nursed my son for his first 6 months, and we would always end up sleeping.

 

[Moonbear]

It's far too oversimplified to refer to oxytocin as a "feel good" hormone. Oxytocin has gained a strange notoriety in the popular press as a "cuddle hormone," based on the work of Diane Witt, among others, who has demonstrated it is involved in affiliative behaviors. Oxytocin has quite a variety of functions, however, including uterine contractility during labor, maternal-infant bonding, milk let-down, etc.

Generally, food deprivation reduces sex behavior. It doesn't make much sense that oxytocin would reduce appetite either. Afterall, lactating women (or lactating females of any species) need to consume a lot of calories to maintain an adequate energy balance and to maintain lactation.

Jumping around a bit...I also wanted to address the comment about some people just having "easy" labors. I don't think any of those women who went without epidurals has an "easy" labor. Yes, some people do have especially difficult labor with or without epidural or anything else. I would never begrudge someone from getting treatment for pain when they are going through an especially difficult labor...and yes, strong contractions beginning before the cervix has even begun dilating, and severe hemorrhaging would count as an especially difficult labor. Actually, that sounds a lot like labor was for some reason premature, perhaps a placental rupture to cause so much bleeding when the baby hadn't even dropped yet? I'm surprised they didn't go ahead and do a c-section in that situation. And it is a personal decision whether someone wants to have an epidural or not. I was just relaying that with a fairly normal labor and delivery, an epidural may not be as beneficial as some think. The truly difficult thing is that by the time the contractions get strong enough to really know if you can tolerate them or not, it's usually too late to get the epidural.

 

[adrenaline]

Might child delivery be easier in females practicing calorie restriction?

I'd be careful here. If a woman's calorie intake is restricted in pregnancy, she may not get enough protein, vitamins and minerals to adequately nourish her unborn child and subsequent low infant birth rate. Low-calorie intake can result in a breakdown of stored fat in the mother, leading to the production of ketones in her blood and urine. Chronic production of ketones can result in a mentally retarded child.
There is also epidemiological data studying pregnant women during wartime/famine conditions that show children borne to that generation have higher predilection for obesity later in life...(some horomonal, chemical, genetic signal turned on due to the fact that the fetus "senses" a starvation environment and thus must adapt to the world it is entering?). (Ravelli AC, Der Meulen JH, Osmond C, et al: Obesity at the age of 50 in men and women exposed to famine prenatally. Am J Clin Nutr 70:811-816, 1999 )

That's why women who undergoe bariatric surgery must gaurantee their surgeon some contraceptive agreement since pregnancies during the post bariatric ketotic state will be very dangerous to the fetus. Then,there is quite the opposite where women pork out and gain too much weight and have gestational diabetes and all its subsequent complications for the fetus. Thus, ob-gyns are always harping on women who gain very little to gain more weight or, for those gaining too much, not to gain so much too quickly (especially those women who think pregnancy is carte blanche to eat like a pig).

 

[Evo]

I was just relaying that with a fairly normal labor and delivery, an epidural may not be as beneficial as some think. The truly difficult thing is that by the time the contractions get strong enough to really know if you can tolerate them or not, it's usually too late to get the epidural.

I would agree. Also, if the epidural doesn't have time to wear off before it's time to push it will cause problems, as Kerrie had.

 

[hitssquad]

Calorie restriction and health of mothers and babies

If a woman's calorie intake is restricted in pregnancy, she may not get enough protein, vitamins and minerals to adequately nourish her unborn child and subsequent low infant birth rate.

Protein, vitamins and minerals might be covered by the N in CRAN and CRON.

Low-calorie intake can result in a breakdown of stored fat in the mother, leading to the production of ketones in her blood and urine. Chronic production of ketones can result in a mentally retarded child.

This might suggest that a CR practicing female should wait until weight-equilibrium has been reached, before commencing insemination.

There is also epidemiological data studying pregnant women during wartime/famine conditions that show children borne to that generation have higher predilection for obesity later in life...(some horomonal, chemical, genetic signal

It is suspected that one of the anti-senescence mechanisms of calorie restriction involves the down-throttling of metabolism. Perhaps the offspring of calorie restricted mothers are well-placed for record-setting life-extension so long as they practice calorie restriction themselves.

There also might be some artificial selecting of data in these famine cases. Fetuses with high mertabolisms may have been subjected to greater rates of spontaneous abortion, shifting the resulting metabolism bell-curve downward.

 

[adrenaline]

I think advocating excercise rather than calorie restriciton, since the former has better data, would be a better form of "calorie restriction"...more like calorie expenditure. Good for mother and baby.
Depending on the study, moderate exercise leads to better weight regulation and fewer backaches and other discomforts. As well as, shorter, easier labors (on average 2 hours less of labor time) with less medical intervention (24%less C-sections and 14% less usage of forceps), higher neo-natal Apgar scores and quicker recoveries etc.
The kids may even have less weight problems. The offspring of exercising mothers measured about 10% less in skinfold and weight measures than those of the non-exercising mothers. Lean muscle mass was higher, particularly in the boys, and percentage of fat was lower. According to national statistics, the children at five years of age of the exercising mothers measured in the 50th percentile for age and skinfold thickness (in a study by a guy at Case Western named Clapp whom is a big reproductive clinical researcher) I think he also concluded that aerobic exercise performed 4 or 5 times per week beginning 6-8 weeks postpartum had no adverse effect on lactation and significantly improved the mother's cardiovascular fitness. And we all know the benefits of breast feeding. With regards to the latter, calorie restriction may once again adversly affect a woman's capability to breast feed,but I don't have the data. From experience, the heavy, sedentary patients seem to have more trouble breastfeeding postpartum perhaps due to their over reliance on calorie restriction for weight loss. It was amazing how many of the athletes or thin, excercising women , including myself, had no trouble breast feeding even with vigorous excercise ( but also hefty amount of food portions.) I was biking on a recumbant bike 60 miles a week by week 2 after delivery and reached my prepartum weight at week 7, but was still able to produce milk for ten months, despite returning to a eighty plus hour work week at the end of six weeks. I believe the only studies really looking at calorie restriction during pregnancy may be confined to the gestational diabetics at this point.

 

[karthik3k]

Poor Females :-(

Thank GOD I am a BOy