Fertility and conception

Fertility and conception

When planning a family, you want to do everything you can to increase the chances of having a healthy baby with your partner.

This means focusing on your health first, especially if you suffer from obesity. If you have obesity and are planning to have a baby in the next few years, you might want to act now to lose weight.

Getting your weight back into the healthy range before you conceive reduces the risk of developing complications during pregnancy and reduces the risk of health problems for your baby.

Obesity is a major cause of health complications and deaths during pregnancy, for both the mother and the baby.

The benefits of treating obesity before becoming pregnant include:

  • Improved fertility
  • Decreased risk of miscarriage or stillbirth
  • Reduced risk of premature labour
  • Reduced risk of the mother developing preeclampsia, gestational diabetes, blood clots, pregnancy-induced high blood pressure
  • Reduced risk of having a baby that is significantly larger than average (over 4kg, which can create health risks for the mother during delivery and for the baby after delivery)
  • Increased rates of successful vaginal birth, including after a previous caesarean delivery
  • Lower operative and infectious complications

Babies born to mothers of a healthy weight are less likely to develop obesity themselves as children and adults. For men, getting down to a healthy weight at least 3 months before trying for a baby can improve both the chances of conception and the health of the baby.

Bariatric surgery is the most effective treatment for obesity.



  • Delay conception for 12-18 months after bariatric surgery
  • Fertility may improve quickly and dramatically, particularly in women whose obesity was associated with reduced or absent ovulation (eg. PCOS)
  • Contraception is essential for all women of reproductive age undergoing bariatric surgery
    • Oral contraceptives may be less effective after Roux-en-Y gastric bypass or duodenal switch (SADI).
    • Non-oral contraception is recommended
    • If possible, women who have undergone bariatric surgery and are planning a family should be referred to an obstetrician with experience in bariatric surgery before becoming pregnant
    • If pregnancy occurs within 12 months of surgery, it is important to return to your surgeon for assessment.