?? The importance of weight in the fertility world - Reproclinic

The importance of weight in the fertility world

Studies have shown that weight can affect fertility in both women and men. A body that is too thin or overweight can present problems in achieving the goal of motherhood. But how does it affect fertility? In this article we explain in more detail this problem experienced by some couples.

The chances of conceiving or having a healthy pregnancy when suffering from a weight problem can be greatly affected. Staying at an ideal weight undoubtedly helps fertility and a smooth pregnancy. Although weight is not a determining factor in getting pregnant or having a healthy pregnancy, some of the hormonal and metabolic alterations that occur when you lose or gain weight can affect ovulation or your ability to get pregnant.

When a couple wants to get pregnant, they look for tips to help them conceive more quickly and healthily. These tips also help us to maintain an ideal weight and have good eating habits. Losing those extra kilos or gaining those that are needed to have a healthy weight are aspects that should be taken into account.

But which is the ideal weight for a woman or a man? One of the methods to determine what weight is ideal is through body mass index, the famous BMI. This is a number that indicates, depending on the height and weight of the person, whether he or she is at the right weight, underweight, overweight or obese.

A BMI below 18.5 indicates excessive thinness and, consequently, an increased risk of ovarian dysfunction and premature birth (before 37 weeks). When the levels are between 18.5 and 25, the person is considered to be of normal weight and therefore has the ideal weight conditions to conceive or carry a pregnancy to term.

On the other hand, a BMI between 25 and 30 indicates overweight, and over 30 obesity. These patients may suffer from certain problems, which are described below.

Approximately 12% of women who are unable to become pregnant are overweight.

What are the consequences of being overweight or obese before pregnancy?

Body fat plays an important role in the production of oestrogen and in blocking gonadotropin-releasing hormone (GbRH). This hormone is responsible for regulating the functioning of the pituitary gland, as well as releasing the hormones FSH and LH. This is a problem that undoubtedly alters the reproductive system in both men and women.

On the other hand, diabetes, hypertension or heart problems are aspects that can arise when a person is overweight, affecting their fertility. Being overweight has a great impact on the ability to conceive. Being unhealthy and overweight can cause insulin levels to rise and thus cause the ovaries to produce more male hormones than normal, disrupting the release of eggs and thus making pregnancy more difficult. So it is not only overweight that affects natural pregnancy, but also the chances of a successful ART. This is due to the myriad of problems that can arise during the cycle, such as:

  • Increased complication during follicular puncture.
  • Worse embryo quality
  • Low response to stimulation.
  • Gonadotropin resistance (thus requiring more ovarian stimulation).
  • Lower probability of fertilisation.
  • Increased risk of cycle cancellation.


As for men, on the one hand, semen quality is altered when the person suffers from obesity, as sperm morphology and concentration worsen; they may have low testosterone levels; suffer from erectile dysfunction; increased risk of oligozoospermia (problems in the quantity of spermatozoa in the sperm), teratozoospermia (abnormal sperm morphology) and asthenozoospermia (abnormal motility patterns); increased likelihood of sperm DNA fragmentation and other alterations.

What complications could arise during pregnancy?

  • Induction, premature births or problems during labour.
  • Gestational diabetes, a problem that can cause pre-eclampsia or hypoglycaemia; increase the chances of caesarean section or of the baby being overfed.
  • Anovulation
  • High birth weight babies. Macrosomia, a term to describe a baby that is larger than average, can complicate vaginal delivery and put the baby at risk of certain injuries during birth.
  • Risk of miscarriages.
  • Syndromes such as polycystic ovary syndrome, endometriosis or the appearance of fibroids are closely related to being overweight, problems that hinder the possibility of conceiving naturally and reduce the chances of successful assisted reproduction.

Reproclinic with the fight against infertility

Weight problems and infertility due to unhealthy weight are aspects that can be reversible. For this reason, at Reproclinic we provide integrative support to all couples who need a nutritional guide to improve their diet, together with exercise. Putting yourself in the hands of this specialist together with assisted reproduction treatment, which increases the chances of pregnancy, will be the key to achieving your dream.

At Reproclinic we will help you prepare your body so that it is in the best conditions to conceive and undergo assisted reproduction treatment. If you need to put on a few extra kilos or get rid of those you have too many, it will be a good time to do it with an expert.

Find out more about the importance of weight in the world of fertility through a first visit with our nutrition coach. Contact us!