Too thin to conceive?

[PrincessDandelion]

Feel a bit silly asking about this...but hey ho.

I had my implant removed last July so as to prepare myself for TTC around new year. Unfortunately, I've still not had a period after 8+ months (I previously had two other implants and so haven't have a proper cycle in years). I don't exhibit any of the typical PCOS symptoms and blood tests have all come back "normal"...

The last time I visited my GP she mentioned that I had a fairly low BMI (I think it was around 18.5). I'm a healthy size 8 so I've never considered myself as underweight, and although I do exercise 5 - 6 times a week and watch what I eat, it is not something I've only suddenly picked up.

So I was just a bit surprised at my GP mentioning this. I was just wondering whether anyone had a similar experience and whether cutting down on exercise or putting on weight had helped?

Thank you!

I am the same size and bmi, exercise hard every day. No problems conceiving.

Makes no difference though. Normal for me may not be normal for you. Whst blood tests did you have?

How tall are? Size 8 at 5'3 might be ok, but not at 6' iyswim.

I'd echo what Grantaire said. I've been TTC for 2 years and at the start, my BMI was slightly higher than yours but my body fat was low due to the type of exercise and training I was doing. I was a size 6 at 5'7". I had a period every month but very irregular (22 days to 36 days) and the doctor suggested some more fat/ weight might be an advantage.

I started adding fat to my diet and not lifting as heavy weights and also shortening my runs a bit. Guess what: I did put some weight on (am now a size 8) but my periods are still haywire and I'm still TTC!

If it wouldn't stress you out to try and up your BMI closer to 20 then give it a bash, it's not going to hurt you. But I think trying to pinpoint fertility issues to a single issue is often really difficult.

xoxo

I had the same BMI as you and wasn't getting pregnant. Purposely out some weight on and got pregnant straight away. Impossible to tell if that was the reason as TTC is unpredictable but I think it was.

Thanks all. I'm 5'6 and around 53kg - not sure I totally believe in the BMI thing anyway as I do lift weights so feel I have quite a lot of muscle (maybe I do need more fat then? ).

The two blood tests I had were for hormone levels... but I'm not sure specifically which hormones were tested - I didn't ask since the results were all "normal".

I can imagine it's hard enough not being able to conceive when you are actually trying, but not even being able to try on account of not having a cycle is just so frustrating too!

xxx

First MN post! I'm 33, 5'8'', have lean PCOS, and am working on getting my BMI up - currently weigh 8'8'' (BMI 18.2)

I've never really had proper periods when not on the pill - could go 6, 9 months without a bleed. Have always been skinny - even at my heaviest I was barely into the 'healthy' BMI range of above 18.5, same frame as my late Mum who was a skinny size 8 well into her 60s. Had always suspected something might not be quite right with my plumbing given highly irregular cycle, so a few years ago I came off the pill to get myself checked out. Took 10 months before a period came on so that I could get my Day 3 hormone levels checked and get scanned etc - showed normal hormone levels but PCO.

I didn't know it was possible to be polycystic and be underweight - had always read it's associated with insulin resistance and being overweight, and the consultant at the fertility clinic pre-empted me with 'I know, you're not fat and hairy but you're still polycystic and have acne (when not on the pill) and don't have periods, you've got lean PCOS'

Anyway, v rambling intro post! I went to see an O&G consultant who specialises in PCOS to discuss plan for TTC - all a bit complex for me as I have epilepsy and also a spinal injury for which I take mega painkillers, both of which have quite significant implications on the TTC process, hence coughing up to go straight to the consultant.

He said I had to have minimum 3 months on prescription strength folic acid before I should come off the pill and we could start treatment (Clomid, starting 50mg), because the epilepsy meds double the risk of birth defects including spina bifada, so have to take the full 3 months of the 5mg folic acid before beginning TTC, currently into month 2.

I asked him about weight and he said really needed to be at an absolutely minimum up to a BMI of 18 (at the time I was more like 17.5) as being underweight significantly reduced chances of treatment working - both getting and staying pregnant - and really I needed to be aiming for 18.5.

I think some NHS trusts specify a minimum BMI of 19 to fund IVF, this is private treatment, and he said my BMI was in part low cos of my height and natural frame, and that it's a blunt tool but the general point of needing to be not underweight was a valid one.

Trying to put the weight on, don't get much sympathy for struggling to get heavier, but I do really find it hard. But the consultant is head of reproductive medicine at Barts Hospital and knows his apples & oranges, so I'm trying my best to do as he says to give myself the best chance once starting on the Clomid. So yes, weight absolutely does come into it, according to my Doc at least!

I had a BMI of 18 before getting pregnant and conceived very easily, although I did have two early miscarriages (now pregnant again and 21 weeks along). I don't think a BMI of 18.5 would stop you ovulating - you'd need to be quite seriously underweight before that happened. It probably wouldn't hurt to try and gain a bit if you can, though- that way at least you can say you've tried.

My friend is a GP and told me I might need to put on weight to conceive (I didn't as it happens), as it's a common reason people can't, but doesn't mean it's the reason your periods haven't come back. Sometimes these things are just 'unexplained', frustrating as that is. The very best thing you can do if the doctors have ruled out all medical barriers is relax and not stress about it. Good luck

p.s. also any good GP should tell you you don't need to be having periods to conceive either. My periods still hadn't come back months after stopping taking it (and it's taken >9 months in the past) and conceived no problems.

p.p.s. what I actually meant to say in my p.s. was just get trying and enjoy yourself!

ApplesTheHare, that's really interesting, though I'm a bit confused :-(

Every Dr I've seen and everything I've read to date (including Taking Charge of Your Fertility) says that it's entirely possible -and indeed more likely amongst women with low body fat & insufficient oestrogen to ovulate - to have periods but not ovulate (anovulatory cycles). But as far as I was aware, it couldn't be the case the other way around - i.e. if you ovulate you will by definition have periods, unless you've fallen pregnant that month! Hormonally if you have ovulated and it hasn't been fertilised and implanted, the lining of the uterus breaks down - obv some people's periods are lighter than others, but don't understand how one could ovulate without then having a menstrual bleed?

Agree 100% that periods can take a while to come back, and that relaxing is so so important. Just a bit confused as to how ovulating-but-not-having-periods works physiologically?

Nice to meet someone in the same boat!

I am 5ft 7 and 7 stone 10 so BMI is 16.9.

I was on the pill for 10 years and was 9 stone 5 when I stoppped taking it. Within a year I had dropped to my current weight and the only cause my GP came up with for the weight loss was stopping the pill.

I have been TTC for 13 months. My periods took 9 months to settle and are now regularly (although fairly light) at every 23 days. However I do not think I am ovulating.

I have been referred to the fertility clinic and told to put some weight on. However I have a long history of an eating disorder and so find it very difficult to increase my food intake.

I am 5'5'' and around 8st. Think bmi around 18. Had my last period jan 2013 and somehow conceived my daughter (with no period) in April 2013. Since stopping bf end of jan I have not had another period and we are keen to ttc #2, not sure how long to wait before going to gp again, just thought I would add my story to say yes you can get pregnant without a period!

I am glad to see others have the same issue as me. I am 5'6", and was 7 st, 38 years old when I went to the fertility clinic in Dec as we have been unable to conceive for 4 years. The consultant said I did not meet the criteria for IVF due to low BMI but that they could ignore this if my GP could provide evidence that my weight was stable. My GP did this as I've weighed exactly the same for 20 years and have a regular cycle, so I am now on the waiting list for IVF. But my GP did say my body may not be able to sustain conception which worries me so I have been desperately trying to put on weight, and with a huge amount of effort I have put on about 8 pounds.

I am not actually convinced that it will make a difference though. I have never done any exercise and considered my low weight just to be my bad luck but also that it was my natural body weight as it didn't fluctuate at all. But who knows, I am determined to keep trying. Even though my skin looks like shit due to all the unhealthy food I'm now eating!
Good luck to everyone.

Years ago I read that body fat percentage is significant in conception. That a woman should have body fat higher than 15%. Your BMI is healthy and similar to mine currently, but if you're muscular and exercise that often it's likely your BF% is lower?

Maybe easing back on the exercise might help? (I'm no doctor, I'm clutching at straws!) best of luck to you.

Ok, so I've gone looking for evidence to back my idea up, which is not particularly scientific but:

"evidence from non-athletic and athletic women and mammals is presented in support of the hypothesis that a particular, minimum ratio of fat to lean mass is normally necessary for menarche (approximately 17% fat/body wt) and the maintenance of female reproductive ability (approximately 22% fat/body wt)."

from: Body fat, menarche, fitness and fertility. Frisch RE, Hum Reprod. 1987 Aug;2(6):521-33.

One study/article doesn't make science. But... 22% seems high, doesn't it?! I'm going to need to eat more pie if we want another...

And for research purposes I'm 5'7"ish and around 57kg, and apparently 16%bf so you at 5'6", 53kg & muscular would probably be much lower.

bananafish I know what you mean. Everything I've read said exactly that, I.e. if you're ovulating you will be having periods, but my friend who is a GP and his wife (also a GP, previously working towards being an obs/gyn consultant but career currently on hold because she's had 3 children in 4 years ) says this isn't the case. Apparently it's not uncommon for women not to be having periods but to conceive. Whether it's the case that they get pregnant the month they first ovulate, I'm not sure. When we were talking about it I was so happy to have got pregnant that I didn't question the getting pregnant without periods bit, just accepted that it's something they see. I don't think it seemed that surprising as a lot of what they talk about (obviously excluding patient details) concern incidents that 'shouldn't be physiologically possible'. Their overall stance seems to be that there are still many things that medicine can't explain, 'not physiologically possible' doesn't actually cover that much, and that individual physiological differences are responsible for a hell of a lot. Something that will kill one person will hardly be noticed by another, etc
etc. I hope that makes sense, I realise it's not the most straightforward (or uplifting!) explanation.

ApplesTheHare - it's awesome!

Hell, if a wonderful thing happens, it's just brilliant news :-)

I guess my very inarticulately expressed thought was that in the vast majority of cases, very irregular or entirely absent periods should be a warning sign demanding further investigation - as it's usually (although clearly not 100% always, yay!) the case that lack of / v infrequent periods = lack of / v infrequent ovulation = much more difficult to get pregnant if there's only an egg there to be fertilised once in a blue moon.

As you say, if you're having v infrequent periods - but not entirely absent - makes total sense that if you have no periods for a while, but then DO have a month when you ovulate, that if you concieve that same month (hurrah!) then you'll get pregnant without the period that WOULD have followed that month ever appearing.

Which is fantastic. But unusual. And given healthy women who do ovulate have a 20% chance of conceiving in a given month if all else is equal, to get pregnant it's really desirable to be ovulating regularly, as all the DTD in the world won't make a baby if there's no egg for the sperm to fertilise. And so obvs not impossible with irregular periods - as this thread is living proof of :-) - but makes it a hell of a lot more difficult / likely to take a hell of a lot longer if there's only a chance of conceiving once in a blue moon.

For me the v v v infrequent periods was due to PCOS - and as PCOS cycles are v often anovulatory, that's why I'm going on Clomid as SOON as I come off the pill - obv if that's been ruled out then it's obv less cut and dried. But v positively, if you're not PCOS then there's lots of evidence that putting on weight can help to regulate periods. Body fat is absolutely key to oestrogen production - so even in my case where I need some oomph to get things going cos of the PCOS, consultant said the treatment had a MUCH greater chance of working if my body fat was at a minimum of 22% (same figure quoted in Taking Charge of Your Fertility) and in the healthy BMI weight range.

Obv these aren't hard and fast - there will always be outliers (as this thread proves) but they're indicative of general overall findings, hence why having enough body fat to ovulate, and ovulating regularly, certainly increases the likelihood of conception for most women. But I'm not a Dr and that's why I'd def recommend consulting a Dr and not some random like me on t'interwebs :-)

Gosh bananfish you sound like you know a hell of a lot about it. I never read much past the basics, as after 20 years of incredibly irregular/absent periods with no identifiable cause I was so terrified about ttc. It makes perfect sense that you can be too thin to conceive though and that laying down a little fat can only help . Good luck to everyone ttc