Greater fertility, vitamin deficiencies may follow bariatric surgery for women

Women who have bariatric surgery should wait until weight loss has stabilized and vitamin levels normalize before trying to get pregnant, according to the results of a systematic review and meta-analysis.

In a review of 51 articles examining associations between bariatric surgery and maternal health of periconception, women who had surgery were more likely to have increased fertility and to have restored regularity of the menstrual cycle compared to to those who have not had surgery, although several studies have found vitamin deficiencies in pregnant women. after bariatric surgery.

“Weight Loss Surgery Improves Fertility Outcome, Without Difference in Rates of Miscarriages and Birth Defects” Katinka Pike, MD, doctoral student in epidemiology of periconception in the department of obstetrics and gynecology of the Erasmus MC University Medical Center and Sam Schoenmakers, MD, PhD, an obstetrician in the Obstetrics and Gynecology department at Erasmus MC University Medical Center, told Healio. “It emphasizes the need to provide and personalize preconception care for women after weight loss surgery. We recommend preconception care, including postponing pregnancy until weight loss has stabilized, regardless of the interval between surgery and pregnancy, and until maternal vitamin status is achieved. standardized. Therefore, regular monitoring of vitamin status and vitamin supplementation to restore deficiencies are recommended.

Katinka pike

Sam shoemakers

Researchers searched the MEDLINE, Embase, PubMed, Web of Science, Google Scholar, and Cochrane databases for studies of bariatric surgery and its effect on maternal health parameters of periconception. Studies examining endocrine changes after bariatric surgery, associations between bariatric surgery, post-surgical vitamin status before conception and during the first trimester, and the prevalence of first trimester miscarriages were included. A meta-analysis was performed on the results of fertility, menstrual cycle, miscarriages and birth defects.

There were 51 articles included in the meta-analysis, of which six looked at malabsorption procedures, 11 looked at restrictive surgery, and 37 looked at a combination of surgeries or did not specify the type of surgery.

Several studies have found changes in vitamin status during pregnancy. In high quality studies, the effect of weight loss surgery on vitamin status was inconsistent. One study found that pregnant women who had Roux-en-Y gastric bypass surgery had a nine-fold higher risk of developing vitamin A deficiency during pregnancy compared to those who had not had surgery , and another study found that 72% of women had inadequate vitamin D status during pregnancy. first trimester of pregnancy after gastric bypass surgery despite daily vitamin D supplementation. Six low-quality studies found weight loss surgery to be negatively associated with levels of vitamin A, B1, B6, B12, folate, C, D and K.

“We advise adequate supplementation, preferably patient-specific, until appropriate serum vitamin levels are reached and weight has stabilized, before a patient tries to become pregnant,” the researchers wrote. “Bariatric surgery has been shown to be effective in reducing weight, but the risks of iatrogenic malnutrition can also influence the growth and development of the fetus and the health of the offspring, although the effects may not be directly visible and are widely. unknown. “

In 20 studies examining the outcome of periconception, women who had bariatric surgery had a reduced risk of infertility (risk difference = -0.24; 95% CI, -0.42 to -0.05) and were more likely to regain the regularity of their menstrual cycle (risk difference = -0.24; 95% CI: -0.34 to -0.15). Weight loss surgery has not been associated with changes in the rate of miscarriages or birth defects. The researchers found substantial heterogeneity in the populations studied, indicating differences in participants, interventions, study design, and variation in effects.

“Although significant weight loss was suspected of leading to decreased infertility, the effect of bariatric surgery on fertility was impressive,” said Snoek and Schoenmakers. “In addition, bariatric surgery was associated with a restoration of a regular menstrual cycle, suggesting a return of hormonal balances.”

Schoenmakers and Snoek said the review revealed the need for longer-term follow-up research during the period of periconception as well as for the offspring. Researchers are currently conducting a continuous prospective cohort of pregnant women who have undergone bariatric surgery who will assess results from the preconception period.

“The possible side effects of over-supplementation should be investigated and the possibilities for an individualized approach should take precedence,” said Snoek and Schoenmakers.

For more information:

Katinka Pike, MD, can be reached at k.snoek@erasmusmc.nl.

Sam Schoenmakers, MD, PhD, can be contacted at s.schoenmakers@erasmusmc.nl.