Weight and conception
Study shows obese women struggle more with falling pregnant and their diet can affect their baby’s health
Trying to fall pregnant but struggling? The answer to your problems could lie in your weight.
Apart from the lifestyle diseases which are an invariable consequence of being overweight, carrying around extra kilograms is also a major contributor to infertility.
Frere Hospital’s Dr Katrin Middleton said Polycystic Ovary Syndrome (PCOS) and sexual arousal disorders were more common in obese women.
PCOS is a condition which affects a woman’s hormone levels, leading her to produce higher-than-normal amounts of male hormones. The result is a hormone imbalance, leading to women skipping menstruation and making it more difficult to conceive.
The specialist obstetrician and gynaecologist explained that even if ovulation did occur, the time to conceive increased and the spontaneous pregnancy rate decreased.
“Therefore weight loss aids in spontaneous conception and reduces the need for fertility treatment,” she said, adding that women planning to conceive should ideally have a normal body mass index (BMI).
The BMI is calculated by dividing weight in kilograms by height in metres squared.
“This should range from 19 to 25,” she explained.
Echoing her words are the findings of a study published in the National Institute of Health’s National Library of Medicine, titled “Obesity as disruptor of the female fertility”.
According to the study, overweight and obese women are said to not only need a longer time to conceive, they are also undoubtedly at a higher risk of infertility.
“Both obesity and [being] overweight are increasing worldwide and have detrimental influences on several human body functions, including the reproductive health,” the study reads.
But it’s not just voluptuous women who should despair, as the weight pendulum swings both ways.
Various media reports from newspapers across the world say being underweight can also play a negative role in fertility.
The reports say being underweight, having a BMI of 18.5 and below, can cause hormone imbalances which affect ovulation and the chances of falling pregnant.
East London-based gynaecologist Dr Robyn Spring explained: “Being underweight means that the body may not have enough nutrition to produce the hormones required to trigger ovulation.”
The solution?
For registered dietician Faaizah Laher, spokesperson for the Association for Dietetics South Africa, aiming for an ideal body weight plus making sure to check on body fat and muscle percentages regularly before conception, was a good start.
Besides, she said, “body positive people are more confident between the sheets, thus making the chance of conceiving that much easier, and fun”.
A nutrient-based, balanced diet is crucial, she added, as healthier eating habits can improve fertility.
She suggests foods such as seafood, lean poultry, whole grains, fruit and vegetables.
Soy and soy supplements appear to exert a beneficial effect in women who are currently undergoing fertility treatments.
“Research now shows that true fertility foods are whole grains, healthy fats and sources of protein – so striking a balance is so important,” she said. “Long chain omega 3 fatty acids boost fertility in women, but it is important to avoid contaminated fish and seafood sources.
“Choose iron-rich foods when trying to conceive, foods high in antioxidants, think all those dark green and colourful vegetables.
“Include less trans-fats and more mono unsaturated fats such as avocados, olives, olive oil, nuts and seeds. Include some vegetable protein, together with animal protein.
“Also, more high fibre, low GI carbohydrates and less refined carbohydrates.”
Alcohol is a no-no and if the diet is restricted, a multivitamin is a must.
“Food sources high in folic acid or a folic acid supplement if your doctor recommends it” are also important, she said.
Depending on the starting weight of the woman, Spring said normal weight gain during pregnancy should fall between 12 to 20kg.
For an obese woman, the weight gain should be minimised – less than 10kg.
Being overweight during pregnancy comes with a number of risks, which include neural tube defects, cardiac malformations, gestational diabetes and gestational hypertension.
“And while this is more dangerous to the mom, there are risks to the baby.
“With gestational diabetes, if it is poorly controlled, the baby can grow bigger than expected, putting mom at risk for a caesarian section.
“And there is an increased risk of stillbirth, even with perfect control of the sugars.
“With the hypertension, there may be the added risk of preeclampsia, leading to a possible early delivery of the baby before due date.” Middleton said pre-pregnancy weight also determined the birth weight of the baby.
“A lot of women deliver a large or macrosomic baby,” she said. “There may be complication in delivery like shoulder dystocia and increased use of instrumental delivery.
“Babies of obese mothers are also prone to obesity later in life.
“Some studies suggest a negative influence of obesity and high-fat diet during pregnancy on the neurodevelopment of the foetus.”
An article which appeared in the UK’s The Telegraph expanded on this last point, citing new research which shows that ensuring your child gets off to the best possible start, physically and cognitively, means planning for pregnancy, not delivery.
Why? Because of the crucial revelation that it is parental behaviour and health, not parental DNA that really matters.
“And if that sounds draconian, another guilt cosh to slug women over the head with, it’s not. It’s actually the incredibly optimistic fruit of a groundbreaking study that crushes ethnic or genetic determinism under the weight of its findings.
“No matter what you look like, or where you live, you can give your children the best start.
“A healthy child is a healthy child, and can hit the same neuro-developmental benchmarks, whether it is born in Somalia or São Paulo or Somerset,” the article reads.
“Meanwhile, in low-income countries, being underweight leads to greater morbidity and mortality, both in the short- and longterm; and to impaired neuro-development, which translates into reduced economic and human capital.”
So whether the pregnant mother is overweight or underweight, a balanced diet plays a major role.
Therefore weight loss aids in spontaneous conception and reduces the need for fertility treatment Dr Katrin Middleton Obstetrician