Obese Britain Summer 2015.pdf

observed to detrimentally effect endometrial development
– the development of the womb lining - and implantation
of the embryo, thereby also leading to an increased risk
of miscarriage.
The commonest hormonal problem experienced by
women is polycystic ovary syndrome (PCOS), an area
that has been the main focus of my research over
the years. The expression of PCOS is regulated, in
part, by weight and so obese women with PCOS
often have more severe symptoms and experience
more sub-fertility.
Obesity also impairs the response of women to
all fertility treatments, which is why the National
Institute of Care Excellence (NICE) advises
that NHS funding for fertility treatment
should not be offered to women with
a BMI of more than 30. Weight
loss through lifestyle modification
or bariatric surgery has been
demonstrated to restore menstrual
regularity, ovulation and improve
the likelihood of conception and a
healthy pregnancy, both naturally and
with treatment.
CASE STUDY
Lucy (not her real name) attended our
clinic eighteen months ago at the age
of 29 and with a BMI of 36, she had
irregular periods but otherwise she and her
husband were healthy. Since puberty she
had struggled with her weight and found
it difficult to exercise. When we explained
the impact this was having on her fertility
she enrolled in a weight management
programme, was careful with her diet
and started to swim and then started
running once her weight started to fall.
She came back to clinic after 6 months
with a BMI of 32, by which time she
didn’t need further encouragement as she
was enjoying feeling fitter. After a further
three months her periods were regular and
she conceived naturally without the need
for treatment.
FACTFILE:
BODY WEIGHT AND FERTILITY
• Fertility is most likely in people with a
normal weight
• Women who are underweight stop having periods
• Women who are overweight and obese have a 2-3
fold reduction in their fertility
• Being overweight increases risks during pregnancy and
also may adversely effect the long term health of children
• Fertility treatments are less likely to work in people who
are overweight
• Weight loss is best achieved by a combination of diet
and exercise
ABOUT THE AUTHOR
ADAM BALEN
Professor Adam Balen MB, BS, MD,
DSc, FRCOG is a full time Consultant in
Reproductive Medicine at Leeds Teaching
Hospitals NHS Trust.
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