'Too thin to conceive' women warned

Being too thin can be just as damaging as being too fat when it comes to getting pregnant, according to new research.

Thinness is associated with fertility problems in couples trying to conceive naturally, often due to underweight women having irregular periods and producing low levels of the hormone oestrogen.



Obesity can also affect the chances of conception, with excess weight linked to irregular periods and conditions such as polycystic ovaries.



But while lots of research has focused on the negative impact of obesity, a new study suggests being underweight is just as bad if not more so.



Experts in Chicago analysed data from 2,362 cycles of IVF involving women under the age of 40.



For women who were underweight - with a body mass index (BMI) of between 14 and 18 - the chance of delivering a healthy baby was 34%.



It was significantly higher (50%) in healthy or slightly overweight women (with a BMI of 19 to 28), and was 45% in very overweight and obese women (BMI of 29 to 43).



Guidelines from the National Institute for Health and Clinical Excellence (Nice) for the NHS say women should ideally have a BMI of 19 to 30 to be accepted for IVF.



However, many primary care trusts (PCTs) set their own weight restrictions on who they will and will not treat.



Dr Richard Sherbahn, from the Advanced Fertility Centre of Chicago, conducted the study and presented his findings at the American Society for Reproductive Medicine (ASRM) conference in Orlando.



He said other research had shown that being too thin was not good for fertility but it was unclear why this should be the case with IVF, when women were given drugs to make them produce eggs.



This should bypass any problems a thin woman may have with period irregularity.



Dr Sherbahn said it was possible, in evolutionary terms, that being too thin may mean the body does not think it is the best time to reproduce.



There may also be differences in the womb's receptiveness to an embryo depending on a woman's weight.



Dr Sherbahn said: "We don't have a really good explanation of the underlying factors.



"The take home message is to have a healthy BMI if possible."



Charles Kingsland, a consultant gynaecologist at the Liverpool Women's Hospital and member of the British Fertility Society, said he was not surprised that being too thin may affect the chances of pregnancy more than being obese.



"If your BMI is 16, 17 or 18 then you are really very thin," he said, adding it was "common" for him to see patients who were underweight.



"If a woman has a BMI of 16 and she has fertility problems, then IVF is not going to cure that," he said.



"It's as if your body's saying 'this is not a good time for me to get pregnant'."



Mr Kingsland said he also sees women with eating disorders.



"One of the hidden significant diseases in our society are eating disorders, which are grossly underestimated.



"Not only does that have a devastating effect on a woman's own health but also on her family as well."



He continued: "There are so many things people can do to help themselves before they intervene and start seeking medical advice.



"It's important to look at body weight, having a good diet which is full of fruit and veg and vitamins and minerals, reducing alcohol, stopping smoking and trying to be active."

PA

Suggested Topics
Voices
voices
Life and Style
Upright, everything’s all right (to a point): remaining on one’s feet has its health benefits – though in moderation
HealthIf sitting is bad for your health, what happens when you stay on your feet for a whole month?
News
newsHad asteroid hit earlier or later in history, the creatures might have survived, say scientists
Arts and Entertainment
Peter Griffin holds forth in The Simpsons Family Guy crossover episode
arts + ents
PROMOTED VIDEO
Life and Style
ebookA wonderful selection of salads, starters and mains featuring venison, grouse and other game
Sport
Laura Trott with her gold
Commonwealth GamesJust 48 hours earlier cyclist was under the care of a doctor
Arts and Entertainment
Gal Gadot as Wonder Woman
arts + entsFilmmaker posted a picture of Israeli actress Gal Gadot on Twitter
News
Bryan had a bracelet given to him by his late father stolen during the raid
people
Arts and Entertainment
Chris Pratt stars in Guardians of the Galaxy
arts + ents
Arts and Entertainment
Pedro Pascal gives a weird look at the camera in the blooper reel
arts + entsPrince Oberyn nearly sets himself on fire with a flaming torch
News
Danny Nickerson, 6, has received 15,000 cards and presents from well-wishers around the world
newsDanny loves to see his name on paper, so his mother put out a request for cards - it went viral
Sport
France striker Loic Remy
sportThe QPR striker flew to Boston earlier in the week to complete deal
News
Orville and Keith Harris. He covered up his condition by getting people to read out scripts to him
People
Arts and Entertainment
Zoe Saldana stars in this summer's big hope Guardians of the Galaxy
filmHollywood's summer blockbusters are no longer money-spinners
Arts and Entertainment
O'Shaughnessy pictured at the Unicorn Theatre in London
tvFiona O'Shaughnessy explains where she ends and her strange and wonderful character begins
Life and Style
Workers in Seattle are paid 100 times as much as workers in Bangladesh
fashionSeattle company lets customers create their own clothes, then click 'buy' and wait for delivery
Independent
Travel Shop
the manor
Up to 70% off luxury travel
on city breaks Find out more
santorini
Up to 70% off luxury travel
on chic beach resorts Find out more
sardina foodie
Up to 70% off luxury travel
on country retreats Find out more
Latest stories from i100
Have you tried new the Independent Digital Edition apps?

ES Rentals

    Independent Dating
    and  

    By clicking 'Search' you
    are agreeing to our
    Terms of Use.

    iJobs Job Widget
    iJobs General

    Data Analyst

    £30000 per annum: Ashdown Group: A highly reputable software house is looking ...

    Application Support Analyst / Junior SQL Server DBA

    £40000 - £45000 per annum: Ashdown Group: An established professional services...

    Commercial Litigation

    Highly Attractive Salary: Austen Lloyd: CITY - SENIOR COMMERCIAL LITIGATION SO...

    BI Developer - Sheffield - £35,000 ~ £40,000 DOE

    £35000 - £40000 per annum + competitive: Progressive Recruitment: My client is...

    Day In a Page

    A new Russian revolution: Cracks start to appear in Putin’s Kremlin power bloc

    A new Russian revolution

    Cracks start to appear in Putin’s Kremlin power bloc
    Eugene de Kock: Apartheid’s sadistic killer that his country cannot forgive

    Apartheid’s sadistic killer that his country cannot forgive

    The debate rages in South Africa over whether Eugene de Kock should ever be released from jail
    Standing my ground: If sitting is bad for your health, what happens when you stay on your feet for a whole month?

    Standing my ground

    If sitting is bad for your health, what happens when you stay on your feet for a whole month?
    Commonwealth Games 2014: Dai Greene prays for chance to rebuild after injury agony

    Greene prays for chance to rebuild after injury agony

    Welsh hurdler was World, European and Commonwealth champion, but then the injuries crept in
    Israel-Gaza conflict: Secret report helps Israelis to hide facts

    Patrick Cockburn: Secret report helps Israel to hide facts

    The slickness of Israel's spokesmen is rooted in directions set down by pollster Frank Luntz
    The man who dared to go on holiday

    The man who dared to go on holiday

    New York's mayor has taken a vacation - in a nation that has still to enforce paid leave, it caused quite a stir, reports Rupert Cornwell
    Best comedians: How the professionals go about their funny business, from Sarah Millican to Marcus Brigstocke

    Best comedians: How the professionals go about their funny business

    For all those wanting to know how stand-ups keep standing, here are some of the best moments
    The Guest List 2014: Forget the Man Booker longlist, Literary Editor Katy Guest offers her alternative picks

    The Guest List 2014

    Forget the Man Booker longlist, Literary Editor Katy Guest offers her alternative picks
    Jokes on Hollywood: 'With comedy film audiences shrinking, it’s time to move on'

    Jokes on Hollywood

    With comedy film audiences shrinking, it’s time to move on
    It's the best of British art... but not all is on display

    It's the best of British art... but not all is on display

    Voted for by the British public, the artworks on Art Everywhere posters may be the only place where they can be seen
    Critic claims 'I was the inspiration for Blanche DuBois'

    Critic claims 'I was the inspiration for Blanche DuBois'

    Blanche Marvin reveals how Tennessee Williams used her name and an off-the-cuff remark to create an iconic character
    Sometimes it's hard to be a literary novelist

    Sometimes it's hard to be a literary novelist

    Websites offering your ebooks for nothing is only the latest disrespect the modern writer is subjected to, says DJ Taylor
    Edinburgh Fringe 2014: The comedy highlights, from Bridget Christie to Jack Dee

    Edinburgh Fringe 2014

    The comedy highlights, from Bridget Christie to Jack Dee
    Dame Jenny Abramsky: 'We have to rethink. If not, museums and parks will close'

    Dame Jenny Abramsky: 'We have to rethink. If not, museums and parks will close'

    The woman stepping down as chair of the Heritage Lottery Fund is worried