where is the evidence for inducing "post term" pregnancy at 42 weeks

[Banjogurl]

Hi, I'm a first time Mum and am 41 weeks today. I'm feeling under pressure to have an induction but believe the official date is one week off and that I am only in fact 40 weeks today.
I'd like to look at the scientific evidence for not going over 42 weeks (I have a background in science) and wondered if anyone could point me in the right direction?

Have a look here. It's your call but I wouldn't want to risk it.

Cochrane review

Interesting personal review

Selection of resources on post-dates pregnancy

Association of Ontario Midwives clinical guideline

I had a pdf I downloaded that analysed all the studies on stillbirth post 41/42 weeks and was really interesting, but I now can't find it and can't find where I downloaded it from because I can't remember the title. Many of the studies are flawed in one way or another. Evidence is rather lacking because the policy of inducing women by 42 weeks or sooner has now been so widespread for so long. Maybe this will ring a bell with someone?

This one too, but not the one I was thinking of.

i heard somewhere that the increased stillbirth risk should be broken down by age and ethnicity because for youngish healthy white women it was lower, but I can't find it now, so it doesn't help you much, and please don't take my word for it because it's a long time since I left university and I may well have totally mis-remembered it.

consider the option of monitoring fetal wellbeing instead of induction. the best way to do this is a combination of things but certainly including dopplers to ascertain placental function. It is often hard to persuade nhs units to do this and they usually offer regular ctgs until they can bully you into being induced you go into spontaneous labour or choose induction at a later date. There are tales of 44 week pregnancies all over the place. Try AIMS or the assocation of radical midwives for more info, as ARM certainly deal a lot with post term pregnancies.

because its about weighing up the risks! being induced has risks as well.

are you sure of your dates op? dating scans can be out by as much as a week or so, i have had this.

i went to 3 wks overdue with one of mine and then was induced as i was fed up! the others i went to 2wks overdue.

there is a website/forum called ten month mamas? or something which has good info and am sure someone else on mnet will be along later with some more links etc for you.

but the increase in risk is statisically tiny, you can have expectant management, where you get more monitering ie every day or every other day and a scan to check fluid levels and placenta function, you may have to push a bit for this but you are entitled to it.

well, because pregnancy is always a balance of risks. I had a VBAC, so I willingly took on the risk that my uterus would rupture. Women having an epidural take on a risk that they will have permanent nerve damage. Women getting pregnant take on the risk that they might die in pregnancy or childbirth. We all make choices based on a very personal assessment of benefits vs risks. OP is a sciency type and quite rightly wants to assess the risk herself and make a choice. Seems quite sensible to me.

pregnancy dating notoriously inaccurate.

I knew that risks of induction plus risks of birth complications due to my psychological state during an induction were far higher FOR ME than the risks of stillbirth.

Thanks for all the comments everyone. I saw a midwife yesterday and have chosen the expectant management route, I will have an ultrasound scan and monitoring on Friday when I am officially 40+10 (40+3 by my own dates) and then make a decision about induction.

I find it a bit worrying that often people blindly trust health professionals often without question. I've worked in health care and in the NHS as a health professional in different areas and have seen first hand that often procedures are set which are blind to the circumstances of individuals and are results/target based. So naturally I wanted to look at the evidence. Thanks Declutterbug for your suggestions.

It seems obvious to me that forcing a baby out before it is ready is not going to be in it's or my best interests. I have read widely and am aware of the risks. I will heed any advice based on the monitoring on Friday. No woman carries a baby for nearly 10 months and wishes for anything else other than a healthy happy baby!

I would absolutely not take the risk. If I get to 40 weeks, I shall be banging on the door to the hospital to get this baby out. The placenta is not designed to last longer than 40 weeks, it starts calcifying sometime before your due date and continues to deteriorate.

I looked at the risks of stillbirth after a few happened in my social group. Going overdue is the number one preventable cause of stillbirth. If you get to 43 weeks, there is a 1:400 chance that your child will be stillborn.

And I am sorry, but these people who bleat on about the risks of induction piss me off. You can't possibly compare the two.

The placenta is not designed to last longer than 40 weeks

Hmm really? That seems like a very rigid time period. You do know that human beings are quite variable and things like maternal age/acurate dating etc must come into play...

Where did you hear or read this GemmaPomPom?

Going overdue is the number one preventable cause of stillbirth

This is simply not true. Placental problems, birth defects/trauma, maternal illness/infection, smoking, obesity and other lifestyle issues related to social deprivation are all major causes.

I think you should get your facts straight before posting!

It starts to deteriorate at quite a rapid rate from a few weeks beforehand. The British Medical Journal published a graph showing the stillbirth rate by gestation week. I would not take the risk.

Then again, I did 3 rounds of IVF to get my baby, so maybe I feel somehow more precious about it than those who are more casual about going overdue and who conceived their babies easily.

Banjogurl, please re-read my post taking note of the word 'preventable'.

I'd say smoking was preventable?

Gemma that's an unforgivable thing to say. Almost all babies are extremely precious to their parents. By all means link to evidence that supports your pov, which you are entitled to, but please do not imply such nasty things about easily conceived babies ( and I didn't go overdue with either of mine, so I did not take personal affront at your words) .

I'd say smoking was preventable?

Smoking increases your chance of stillbirth by 200%. The chances of your child succumbing to stillbirth increase by 300% from Week 38 to Week 43.

what a vile thing to say gemma and yes i did conceive easily and went overdue, with careful monitering to make sure my babies were ok and each and every time afterwards they inspected my placenta which showed NO signs of deterioration even when i went 3wks with ds3! i had huge placentas and big babies, i just cook them well! my mum also went overdue, i think there is research to show maternal history plays a aprt.

also when dating you they do it from your last period, there is NO placenta at that point so your placenta isnt 40wks old at your due date anyway! plus they use an 'average' 28 day cycle to come up with your date and not everyone has an 'average' cycle. and dating scans are known to be innacurate.

btw as i conceived so easily and have had 5 healthy children, i was an ideal candidate for egg donation so i have donated eggs to help a couple to have their own baby, i couldnt imagine the pain of having to struggle to have a child so did something very simple that i could do to help give someone that chance. any baby conceived via my eggs or any kind of ivf isnt more special than any of mine they are all individuals and equally precious to me and most parents.

and you say the risk increases by 300% but what you fail to mention is it is still a tiny percentage overall and actually the risk to induction can also include stillbirth, complications for the baby, and the mother. childbirth inherintly has risks, its a case of weighing them up to find out what is the best for each individual.

you dont want to go overdue, that is your choice, but dont knock others who make a different choice and insinuate that they somehow love their child less.

you say the risk increases by 300% but what you fail to mention is it is still a tiny percentage overall

So, are you saying that those tiny percentage of babies don't matter, then?

no that isnt what i said at all, can you not read?!

just that you say its a 300% increase but when its a 300% increase of what was 0.0003% or whatever then its still not a high number. but yes every baby matters of course they do and i never said htey didnt, YOU are the one who made out your baby is more precious and that you somehow value its life more.

the point is there are risks in everything, including in being induced which can still lead to complications including stillbirth! the risks have to be weighed up no an individual basis.

My first was damaged during birth by modern birthing methodologies. I would never risk that again. Placentas really do not deteriorate that fast for the majority and there are risks to the baby of being expelled too early, as well as being pumped full of various drugs that interfere with he hormones and birthing process.

It is very rare that a woman refuses induction for post dates without a) very good well researched reasons and b) a bit of a battle to demonstrate knowledge.

Fetal monitoring is the key here.

When I was a practising midwife I was personally involved with 3 still births where the woman had refused induction despite fetal monitoring demonstrating rapidly deteriorating function.

Many pregnancies last longer then 40 weeks and all is well.

It isn't the length of the pregnancy per se that is the most important factor, but the fact that there is an association between the length of the pregnancy and the plancental function.

Careful monitoring, interpretation by experienced obstetricians, and willingness to take their advice is what matters.

Placental. My typing is getting worse.

would you care to link to those stats?

because according to the stats on the NICE guidance, week 41 was 0.3, week 42 was 0.4 level of incidence. (1991 stats, Scotland) without breakdown of primip/ multip.

and the wording used to say 'the risks of induction were outweighed at 42 weeks' - many trusts do not induce purely for post dates until 42 weeks.

induction is a major intervention and one with its own risks.

for some reason the page that comes from isn't working, but if you google 'NICE guidance on induction' it should come up...

also average gestation length has been increasing - no-one knows how valid those studies are twenty years on. 40 weeks is just the average as was 50/60 years ago....41 weeks is more like it now.

personally i would not accept induction for dates of any kind prior to 42 weeks as you are really likely to go into spontaneous labour before then (60% that make it to +10 will labour in the next three days.) ...

can i ask gemma you say if you get to 40 wks you will be wanting an induction, but they wont actually induce you at 40 wks unless there is medical reason to do so, with my last baby i actually got induced at temr plus 10 as i had concerns, they didnt want to induce me (bizarre as iwth my others the policy was to induce at +10 and i had to battle to go to +14) there were a variety of factors that influenced my decision to get induced at term plus 10, but i had to see a consultant and have a scan and monitering etc ot get them to agree to it.

you may get them to agree to it on the basis that your baby was concieved via ivf, which i think statistically makes you slightly higher risk? but you will have to have a good reason for getting induced at term rather than going the 10-14days over which is nice policy. most hospitals it is now 14days some still induce at 10 days (my trust was on of the last ones to change to 14 days)

as it is the op is having a scan and montering at term plus 10 by hospital dates (or plus 3) by her dates so she is checking on the well being of her baby and then making an informed choice as to how overdue she will go.

op fingers crossed you dont make it to the scan and go into labour before then! if not most places say term plus 14days so you still have another few days, once plus 14days you can go the expectant management route and see how you and baby are :) good luck :)