In this blog post, we discuss how excess body weight affects fertility and pregnancy, as well as what to be aware of about pregnancy after weight loss surgery.
Obesity and Fertility in Females
Weight – whether too high or too low — can affect a woman’s ability to get pregnant, have a healthy pregnancy and deliver a healthy baby.
The relationship between obesity and female fertility is complex and multifactorial.
Excess body weight has been shown to:
- Increases the amount of oestrogen in the body.
Oestrogen is a hormone produced by ovaries as well as fat cells. Weight gain causes fat cells to grow and produce more oestrogen than needed. This disrupts regular ovulation and can result in irregular menstrual cycles.
- Increases the risk of insulin resistance.
Insulin resistance refers to when the body needs to produce more and more insulin to keep blood sugar levels at bay. High amounts of insulin in the blood has been linked to metabolic disturbances that affect ovulation.
Obesity Pregnancy Risks
Obesity also increases the risk of almost all pregnancy complications in women, including:
- Gestational diabetes mellitus (elevated blood sugar levels during pregnancy)
- Gestational hypertension and preeclampsia (a pregnancy complication characterised by high blood pressure)
- Delivery of large for gestational age (LGA) infants
- Blood clots
- A higher incidence of miscarriages, cesareans and congenital defects in newborns
Obesity and Fertility in Males
Being overweight or obese can affect a man’s fertility by causing hormonal imbalances (lower testosterone) and diminishing total sperm count and quality.
In addition, studies have also shown obesity to be linked with erectile dysfunction.
Fertility after Bariatric Surgery
Due to significant weight loss, most women find their fertility levels rapidly increase after bariatric surgery.
We recommend waiting for at least 12 months before trying for a baby due to the following reasons:
- Inadequate maternal nutrition to support a healthy pregnancy
- Inadequate weight gain, resulting in a poor supply of nutrients to the baby
- Low birth weight and an increased risk of developmental delays in the baby
- Breastfeeding may also be a challenge due to increased requirements for calories and fluids
Weight Loss Surgery and Pregnancy
Pregnancy after bariatric surgery can be safe and healthy, with the help of a multidisciplinary team supporting you.
It is important to:
- Cease bariatric specific multivitamins immediately due to the high vitamin A content. Start taking a pregnancy safe multivitamin prescribed by your GP throughout pregnancy and breastfeeding
- Get regular blood tests to monitor vitamin and mineral levels and to prevent micronutrient deficiencies
- See your GP and monitor for appropriate weight gain throughout your pregnancy
- Continue to see a dietitian for a pregnancy specific meal plan
- Aim for 5-6 small nutritious meals throughout the day
- Aim for adequate fluid intake (at least 2L per day)
- Speak to a physiotherapist or exercise physiologist to ensure you are able to remain physically active during pregnancy.