How soon after bariatric surgery is it safe for me to get pregnant? This is a common question from young women who are thinking of a gastric band, gastric bypass or sleeve gastrectomy for weight loss. We know that weight loss surgery can have huge health benefits. The worry is whether weight loss surgery may be harmful to the baby. In an earlier post, we explored the benefits and risks to both mother and baby. In this post, we will look at the safe interval between weight loss surgery and pregnancy.
Benefits of Pregnancy After Weight Loss Surgery
Weight loss increases the safety of pregnancy and delivery in many ways. The mother’s risks for high blood pressure and diabetes during pregnancy are substantially lower after weight loss surgery. Also, the risk that baby may be large for gestational age is significantly lower after weight loss surgery. Also, the rate caesarean section is much lower after weight loss surgery
Risks of Pregnancy After Weight Loss Surgery
But, there is worry that weight loss surgery can harm the development of the baby because the mother has nutritional deficiencies. Studies have shown that the risk for small for gestational age babies is increased after gastric bypass surgery. Also, there seems to be increased risk for premature delivery. For detailed information about these risks, see our earlier post.
Does the Timing of Pregnancy after Bariatric Surgery Matter?
Weight loss surgery increases the safety of pregnancy and delivery in many ways. But, it does increase the risk of preterm delivery and small for gestational age babies. The important question is whether these increased risks come down with time. Can pregnancy after weight loss surgery be timed to reduce these risks?
Generally, weight loss takes place during the first 1-2 years after the operation. After a gastric bypass or gastric sleeve, most of the weight loss happens during the first year. Although, some more weight can be lost in the second year. After a gastric band, weight loss is usually spread out over 2 years. Most women will have reached their new steady weight by the end of two years.
The body is a said to be in a ‘catabolic’ state during weight loss. Catabolic means breakdown. When weight is being lost, the body’s stores of fat are being broken down. Complex changes take place in the human body. Deficiencies of energy, vitamins and minerals can develop during this period. Pregnancy puts extra nutritional demands on the mother. During the catabolic phase, the mother’s body may not be able to cope with these extra demands.
What is the Safe Interval for Pregnancy after Bariatric Surgery?
The American College of Gynaecologists has recommended that pregnancy should be avoided for 12-24 months after weight loss surgery. Suitable contraception should be used so that pregnancy is spaced after the operation. A 2-year safety interval is logical and sensible advice. But, until recently, the actual safety of a 2-year interval had not been tested.
What is the Recent Scientific Evidence on Pregnancy after Bariatric Surgery?
Researchers from the University of Washington analysed data on births in Washington State, USA, between 1980 and 2013. There was a total of 2.6 million births. Of these, 1859 births were to mothers who had previous weight loss surgery. The researchers compared the risks between weight loss surgery-mothers and mothers from the general population. They divided the weight loss surgery mothers into three groups. The first group was mothers who became pregnant and delivered within 2 years after their weight loss operation. The second group had mothers who delivered between 2 and 4 years after their operation. The third group had mothers who delivered at more than 4 years after their operation.
Let’s look at three important findings from this study:
First, let’s look at the mothers who became pregnant and delivered within 2 years after their weight loss operation. As expected, the rates of preterm delivery and small for gestational age babies were significantly higher in comparison to the general population.
Second, let’s look at the mothers who delivered between 2 and 4 years after weight loss surgery. They had higher risk for small for gestational age babies. In fact, their risk was similar to the risk for mothers who delivered at less than 2 years. But, the risk for preterm births was not different from the general population.
Finally, let’s look at the weight loss surgery mothers who delivered after 4 years. The risk of preterm delivery and small for gestational age babies was not different from the general population. So, after 4 years the risks seem to come down to the baseline risks that apply to any pregnancy.
How long should I wait after weight loss surgery to get pregnant?
The bottom line seems that it is safest to wait for about 4 years after weight loss surgery to get pregnant. But, these findings come from only one study. Like most medical studies, there are several shortcomings in this study. Regardless, there is a clear message: it is important to not plan pregnancy soon after weight loss surgery.