Pregnancy after bariatric surgery: a review

Midgut Volvulus Evolving From Internal Herniation Following Roux-en-Y Gastric Bypass Surgery

In the literature, midgut volvulus is a well-known surgical complication following gastric bypass surgery that is serious and necessitates an immediate intervention. Here, we report a case of internal herniation that was misdiagnosed twice but eventually managed appropriately. A 27-year-old male with a surgical history of Roux-en-Y gastric bypass came to the emergency department complaining of severe epigastric abdominal pain. Two months earlier, he had a similar pain which was treated with Helicobacter pylori eradication therapy. Despite completing the eradication therapy, the pain reoccurred. Computed tomography angiography showed a filling defect in the superior mesenteric artery that was followed by a diagnostic laparoscopy ending with internal hernia reduction. Physicians should consider internal herniation as a differential diagnosis for every patient with a history of gastric bypass surgery presenting with abdominal pain.

Nutritional Implications of Bariatric Surgery on Pregnancy Management-A Narrative Review of the Literature

One in three women of reproductive age is obese. The mainstay treatment for obesity is bariatric surgery, and the following weight reduction results in a decrease in pregnancy adverse effects, including gestational diabetes mellitus, pregnancy-induced hypertension, and macrosomia. However, nutritional and vitamin deficiencies due to changes in the gastrointestinal tract after bariatric surgery are associated with an increase in the risk of fetal growth retardation and small for gestational-age neonates. The purpose of this review was to analyze the available recent literature on the subject of the management of pregnancy after bariatric surgery. We searched for available articles from 2007 to 2023 and chose articles of the greatest scientific and clinical value. Micronutrient, vitamin, and protein supplementation is recommended in the prenatal period and throughout the pregnancy. It is advised that pregnant women with a history of bariatric surgery should be provided with regular specialist dietary care. There is still a lack of recommendations about the optimum gestational weight gain after different types of bariatric surgery and for patients of different metabolic statuses. Women of reproductive age undergoing bariatric procedures should be provided with appropriate counseling about adequate contraception, the recommended time-to-conception interval, and the positive and negative influence of bariatric surgery on perinatal outcomes.

Micronutrients in Pregnancy after Bariatric Surgery: A Narrative Review

Bariatric surgery is increasingly used in women of childbearing age due to the rising prevalence of obesity and the effectiveness and availability of this treatment. Pregnancy in women with previous bariatric surgery deserves special attention. Weight loss induced by surgery reduces the risks that obesity poses to pregnancy. But on the other hand, decreased intake and malabsorption may increase the risk of malnutrition and micronutrient deficiency and negatively affect maternal and foetal health. The aim of this narrative review is to provide an updated analysis of the impact of different bariatric surgery techniques on mineral and micronutrient nutritional status during pregnancy and the possible effect on maternal-foetal health.

A Women's health perspective on managing obesity

While the prevalence of obesity in US men and women is nearly equivalent, obesity management in women requires a different approach that considers age and life stage in development including sexual maturation/reproduction, menopause and post-menopause. In this review, the diagnosis and treatment of obesity using lifestyle modification, pharmacotherapy and metabolic and bariatric surgery are discussed from a women's health perspective, with emphasis on management during pregnancy and post-partum.

Weight Changes, Nutritional Intake, Food Contaminants, and Supplements in Women of Childbearing Age, including Pregnant Women: Guidelines for Interventions during the Perinatal Period from the French National College of Midwives

Adequate maternal nutrition is crucial for a healthy pregnancy and optimal fetal growth. Many women in France of childbearing age start their pregnancy in an unfavorable nutritional status. Recent studies highlight the value of paying attention to weight issues from the preconceptional period. It is important to call attention to the need for folate supplementation and to promote a varied and balanced diet throughout pregnancy to cover essential nutritional needs.

[Moderate anaemia refractory to oral iron in a pregnant woman with a history of bariatric surgery]

Introduction

Introduction: bariatric surgery involves nutritional and trace element deficiencies that may have a negative impact if not treated properly, especially in situations such as pregnancy. Case report: a patient who underwent biliopancreatic diversion surgery without subsequent therapeutic adherence consults due to edema; findings included 29-week gestation (type 1 intrauterine growth restriction) and moderate anemia. Vitamin supplementation, oligoelements, enteral nutrition, and intravenous iron were restarted. Due to poor hemoglobin response with repleted iron deposits, recombinant human erythropoietin was associated. Discussion: the most frequent nutritional deficiencies after malabsorptive bariatric surgery are sideropenia and hypoproteinemia. Sideropenia and anemia increase the risk of preterm delivery, low weight, and perinatal mortality. In patients with inadequate response to intravenous iron, treatment with recombinant human erythropoietin may be considered, although its use in pregnant women without chronic renal failure has no indication in the prescribing information of this drug.

The Acute Abdomen in Pregnant Women After Roux-en-Y Gastric Bypass: Encouraging Results from a National Referral Centre

BACKGROUND

Pregnant women with a history of bariatric surgery (BS) may develop acute abdominal pain related to this surgery, especially after Roux-en-Y gastric bypass. Studies showed alarming results regarding maternal and foetal morbidity and mortality. The aim of this study was to analyse these outcomes for pregnant women and their offspring.

METHODS

Single-centre retrospective cohort study in a tertiary referral centre for bariatric complications during pregnancy. Pregnant women with a history of BS referred between September 2015 and November 2019 with acute abdominal pain suspected for a bariatric complication were included. Data were retrospectively collected from the patient files, and a questionnaire was sent regarding the postoperative course and childbirth.

RESULTS

Fifty women were included. At presentation, mean maternal age was 31 (± 4) years, and median gestational age was 28⁺⁴ (25⁺⁴, 30⁺⁵) weeks. Thirteen women were treated conservatively. Thirty-seven women underwent surgery for, among others, internal herniation (n = 26) and intussusception (n = 6). Six women required small bowel resection. Two women underwent an emergency caesarean section shortly after the surgery due to foetal distress. Eight women delivered preterm of whom five infants required respiratory support. There was one intrauterine foetal death. Surgery > 48 h after the onset of the symptoms was not associated with an increase in small bowel resections or preterm birth.

CONCLUSION

Acute abdominal pain in pregnant women may be related to a bariatric complication. Further awareness of bariatric complications within the obstetric care and transferal to specialized care to prevent diagnostic delay may improve maternal and neonatal outcome.

Effect of a Short Message Service Intervention on Excessive Gestational Weight Gain in a Low-Income Population: A Randomized Controlled Trial

Objectives: The objective of this trial was to investigate the effect of educational short message service (SMS), or text messages, on excessive gestational weight gain (GWG) in a low-income, predominantly overweight/obese population. Methods: Participants (n = 83) were mostly overweight/obese women recruited at Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) clinics on the island of O’ahu, Hawai’i at 15–20 weeks gestational age. The intervention group received SMS on nutrition and physical activity during pregnancy designed to help them meet Institute of Medicine (IOM) guidelines for GWG and American College of Obstetricians and Gynecologists guidelines for exercise, respectively. The control group received SMS about general health topics during pregnancy, excluding nutrition and physical activity. Both groups received one text message per week for eighteen weeks. GWG was defined as the difference between the last self-reported weight taken before delivery and participants’ self-reported weight before pregnancy. Differences between study groups were examined using t-tests and Chi-square tests. Linear regression models were used to examine association of GWG with study group and other factors. Results: GWG was similar (p = 0.58) in the control group (14.1 ± 11.4 kg) and the intervention group (15.5 ± 11.6 kg). The percentage of participants exceeding IOM guidelines for GWG was similar (p = 0.51) in the control group (50.0%, n = 17) and the intervention group (60.5%, n = 23). Conclusions: GWG was not significantly different between intervention and control groups. Trials that begin earlier in pregnancy or before pregnancy with longer intervention durations and varying message frequency as well as personalized or interactive messages may be needed to produce significant improvements.

Effects of laparoscopic sleeve gastrectomy on obstetric outcomes within 12 months after surgery

AIM

To determine the obstetric and neonatal outcomes of pregnant patients having undergone laparoscopic sleeve gastrectomy (LSG) in the previous 12 months.

METHODS

This retrospective and observational study included 144 pregnant women: 48 had pregnancies within 12 months after LSG (Group A), 42 became pregnant more than 1 year after surgery (Group B) and 54 obese pregnant women who had a body mass index (BMI) >30 kg/m² , were categorized as the control group because they did not undergo surgery (Group C). The participants' early gestational BMI, predelivery BMI and gestational weight gain were determined and the obstetric and neonatal outcomes of the groups were compared.

RESULTS

The time interval from surgery to conception was 7.8 ± 3.4 months and 25.8 ± 13.4 months for Groups A and B, respectively (P < 0.01). There were no significant differences in the rates of gestational hypertension, pre-eclampsia, preterm delivery and cesarean section between the groups. The number of patients with gestational diabetes mellitus was significantly higher in Group C than in Groups A and B (P = 0.004). The number of large-for-gestational-age infants was higher in Group C than in Groups A and B (P = 0.046). The number of small-for-gestational-age infants was significantly higher in Group A than in Groups B and C (P = 0.025).

CONCLUSION

Pregnancy within one year after LSG is related to an increased risk of small-for-gestational-age infants. LSG decreases the risk of gestational diabetes mellitus independent of the time interval between surgery and conception.

A Review of Obstetrical Outcomes and Complications in Pregnant Women after Bariatric Surgery

Bariatric surgery (BS) is a novel treatment for weight reduction with longer lasting health benefits. This review aimed to summarise the available evidence regarding the fetomaternal outcomes and the most common challenges and complications in pregnancies following BS. Google Scholar (Google LLC, Mountain View, California, USA) and PubMed® (National Library of Medicine, Bethesda, Maryland, USA) databases were searched for articles published until December 2018. A total of 64 articles were included in this review and results showed that BS mitigates the risk of gestational diabetes mellitus, hypertensive disorders in pregnancy and fetal macrosomia. However, it can also have detrimental effects on fetomaternal health. There is paucity of data regarding small for gestational age intrauterine growth restriction, premature rupture of membranes and long-term effects on the children born to women who underwent BS.

Pregnant patient with acute abdominal pain and previous bariatric surgery

Pregnant women who previously had bariatric surgery may develop acute abdominal pain during pregnancy. Two patients, 38-year-old twin primigravida (gestational age of 24+6 weeks) and a 26-year-old woman (gestational age of 24+0 weeks), both of whom had laparoscopic gastric bypass surgery previously, developed abdominal pain. The patients both had diffuse abdominal pain in combination with normal blood tests and imaging. Patient B had undergone laparoscopy at another centre after 5 weeks of gestation for internal herniation. After referral to our multidisciplinary bariatric-obstetric-neonatal (MD-BON) team, diagnostic laparoscopy was advised as internal herniation was deemed possible. In both patients, internal herniation was indeed found in Petersen's space and jejunal mesenteric defect, which was closed using laparoscopic surgery. Both women delivered healthy offspring afterwards. The presence of an MD-BON team allows for an increased awareness of potential long-term complications associated with earlier bariatric surgery in pregnancy.

An association between maternal weight change in the year before pregnancy and infant birth weight: ELFE, a French national birth cohort study

BACKGROUND

Weight-control interventions in pregnant women with overweight or obesity have limited effectiveness for fetal growth and birth outcomes. Interventions or prevention programs aiming at the pre-pregnancy period should be considered. However, how the woman's weight change before pregnancy affects fetal growth is not known. We investigated the association between weight change over the year before pregnancy and birth weight.

METHODS AND FINDINGS

We used the inclusion data of 16,395 women from the ELFE French national birth cohort, a nationally representative cohort in which infants were enrolled at birth with their families in 2011. Maternal weight change was self-reported and classified into 3 groups: moderate weight variation or stable weight, weight loss > 5 kg, and weight gain > 5 kg or both weight loss and gain > 5 kg. Multiple linear regression models were used to investigate the association between pre-pregnancy weight change and a birth weight z-score calculated according to the French Audipog reference, adjusted for a large set of maternal characteristics. The analyses were stratified by maternal body mass index (BMI) at conception (<25 versus ≥25 kg/m2) and adjusted for BMI within these categories. We used the MacKinnon method to test the mediating effect of gestational weight gain (GWG) on these associations. Mother's mean age was 30.5 years, 87% were born in France, and 26% had overweight or obesity. For women in either BMI category at conception, GWG was more than 2 kg higher, on average, for women with weight loss before pregnancy than for women with stable weight or moderate weight variation. For women with BMI < 25 kg/m2 at conception, birth weight was significantly higher with weight loss than stable weight before pregnancy (β = 0.08 [95% CI 0.02; 0.14], p = 0.01), and this total effect was explained by a significant mediating effect through GWG. For women with BMI ≥ 25 kg/m2 at conception, birth weight was not associated with pre-pregnancy weight loss during the year before pregnancy. Mediation analysis revealed that in these women, the direct effect of pre-pregnancy weight loss that would have resulted in a smaller birth weight z-score (β = -0.11 [95% CI -0.19; -0.03], p = 0.01) was cancelled out by the GWG. The mediating effect of GWG was even higher when weight loss resulted from a restrictive diet in the year before pregnancy. Weight gain before pregnancy was not associated with birth weight. Although we included a large number of women and had extensive data, the only potential cause of pre-pregnancy weight loss that was investigated was dieting for intentional weight loss. We have no information on other potential causes but did however exclude women with a history of pre-pregnancy chronic disease. Another limitation is declaration bias due to self-reported data.

CONCLUSIONS

Health professionals should be aware that GWG may offset the expected effect of weight loss before conception on fetal growth in overweight and obese women. Further studies are required to understand the underlying mechanisms in order to develop weight-control interventions and improve maternal periconceptional health and developmental conditions for the fetus.

Pregnancy after bariatric surgery: Maternal and fetal outcomes of 39 pregnancies and a literature review

AIM

We aimed to evaluate the impact of bariatric surgery (BS) on maternal and fetal outcomes.

METHODS

A retrospective, descriptive, observational study of 39 pregnant women who underwent BS in our institution between 2010 and 2014 was carried out. A sample of women who became pregnant after BS was evaluated, based on data concerning pregnancy, childbirth, and newborns.

RESULTS

Of the 1182 patients who underwent BS at our institution during the study period, 1016 (85.9%) were women. Thirty-nine of these women (with an average age of 31 ± 4.8 years) became pregnant (one twin pregnancy) and 29 of the 39 had undergone a gastric bypass. The mean time interval between BS and pregnancy was 16.6 ± 4.8 months; however, 16 (41%) women became pregnant less than a year after BS. The pre-BS body mass index (BMI) of the 39 women was 44.5 ± 6.2 kg/m² . The women had a mean BMI of 30.2 ± 3.8 kg/m² when they got pregnant and they gained 13.2 ± 7.3 kg during pregnancy. Iron deficiency was observed in 18 (46.1%) women, 16 (45.7%) had vitamin B12 deficiency, 12 (66.8%) had zinc deficiency, and 20 (60.6%) had vitamin D deficiency. Three women developed gestational diabetes mellitus. Premature rupture of membranes occurred in two pregnancies, preterm delivery in five, and there was one spontaneous abortion. Cesarean section was performed in seven cases. The average newborn weight was 3002 ± 587 g, five were small for gestational age, and one had macrosomia. Three infants had to be admitted to an intensive care unit.

CONCLUSION

Although pregnancy after BS is safe and well tolerated, close monitoring by a multidisciplinary team is required to evaluate complications resulting from BS, especially a deficit of micronutrients.

Adverse effects during the oral glucose tolerance test in post-bariatric surgery patients

OBJECTIVE

The oral glucose tolerance test (OGTT) is used in the screening of gestational diabetes, in diagnosis of type 2 diabetes in conjunction with fasting blood glucose and glycated hemoglobin. The aim of this study was to examine the incidence and risk factors of adverse effects of OGTT in patients who underwent bariatric surgery, in addition to proposing standardization for ordering the OGTT in these patients.

SUBJECTS AND METHODS

This study assessed the incidence of adverse effects in 128 post-bariatric surgery patients who underwent the OGTT. Descriptive and logistic regression analysis were performed, the dependent variables were defined as the presence of signs (tremor, profuse sweating, tachycardia), symptoms (nausea, diarrhea, dizziness, weakness), and hypoglycemia (blood glucose ≤ 50 mg/dL).

RESULTS

One hundred and seventeen participants (91.4%) were female; 38 (29.7%) participants were pregnant. High incidence (64.8%) of adverse effects was observed: nausea (38.4%), dizziness (30.5%), weakness (25.8%), diarrhea (23.4%), hypoglycemia (14.8%), tachycardia (14.1%), tremor (13.3%), profuse sweating (12.5%) and one case of severe hypoglycemia (24 mg/dL). The presence of signs was associated with hypoglycemia (OR = 8.1, CI 95% 2.6-25.1). The arterial hypertension persisted as a risk factor for the incidence of signs (OR = 3.6, CI 95% 1.2-11.3). Fasting glucose below 75 mg/dL increased the risk of hypoglycemia during the test (OR = 9.5, CI 95% 2.6-35.1).

CONCLUSION

In this study, high incidence of adverse effects during the OGTT was observed in post-bariatric surgery patients. If these results are confirmed by further studies, the indication and regulation of the OGTT procedure must be reviewed for these patients.

A short-term transition from a high-fat diet to a normal-fat diet before pregnancy exacerbates female mouse offspring obesity

BACKGROUND/OBJECTIVES

Recent findings have highlighted the detrimental influence of maternal overnutrition and obesity on fetal development and early life development. However, there are no evidence-based guidelines regarding the optimal strategy for dietary intervention before pregnancy.

SUBJECTS/METHODS

We used a murine model to study whether switching from a high-fat (HF) diet to a normal-fat (NF) diet (H1N group) 1 week before pregnancy could lead to in utero reprogramming of female offspring obesity; comparator groups were offspring given a consistent maternal HF group or NF group until weaning. After weaning, all female offspring were given the HF diet for either 9 or 12 weeks before being killed humanely.

RESULTS

H1N treatment did not result in maternal weight loss before pregnancy. NF offsprings were neither obese nor glucose intolerant during the entire experimental period. H1N offsprings were most obese after the 12-week postweaning HF diet and displayed glucose intolerance earlier than HF offsprings. Our mechanistic study showed reduced adipocyte insulin receptor substrate 1 (IRS1) and hepatic IRS2 expression and increased adipocyte p-Ser(636/639) and p-Ser(612) of H1N or HF offspring compared with that in the NF offspring. Among all groups, the H1N offspring had lowest level of IRS1 and the highest levels of p-Ser(636/639) and p-Ser(612) in gonadal adipocyte. In addition, the H1N offspring further reduced the expression of Glut4 and Glut2, vs those of the HF offspring, which was lower compared with the NF offspring. There were also enhanced expression of genes inhibiting glycogenesis and decreased hepatic glycogen in H1N vs HF or NF offspring. Furthermore, we showed extremely higher expression of lipogenesis and adipogenesis genes in gonadal adipocytes of H1N offspring compared with all other groups.

CONCLUSIONS

Our results suggest that a transition from an HF diet to an NF diet shortly before pregnancy, without resulting in maternal weight loss, is not necessarily beneficial and may have deleterious effects on offspring.

Obesity and reproduction: a committee opinion

The purpose of this ASRM Practice Committee report is to provide clinicians with principles and strategies for the evaluation and treatment of couples with infertility associated with obesity. This revised document replaces the Practice Committee document titled, "Obesity and reproduction: an educational bulletin," last published in 2008 (Fertil Steril 2008;90:S21-9).

Mid-term results of laparoscopic sleeve gastrectomy and Roux-en-Y gastric bypass in adolescent patients

The prevalence and severity of obesity in children and adolescents has been increasing in recent years at an unprecedented rate. Morbidly obese children will almost certainly develop severe comorbidities as they progress to adulthood, and bariatric surgery may provide the only alternative for achieving a healthy weight. The aim of this study was to assess the long-term outcomes and safety of laparoscopic sleeve gastrectomy (LSG) and Roux-en-Y gastric bypass (RYGB) as new treatment modalities for morbidly obese adolescents. We conducted a retrospective review of a prospectively collected database of all adolescent patients who underwent LSG and RYGB under IRB protocol at the Bariatric and Metabolic Institute in Cleveland Clinic Florida between 2002 and 2011. Patients were also contacted by phone, adhering to HIPAA regulations, and were asked to answer a survey. Eighteen adolescents had a bariatric procedure performed at this institution. The mean age was 17.5 years, the average weight was 293.1 lbs, and the average BMI was 47.2 kg/m2. The mean follow-up period consisted of 55.2 months. The postoperative weight at 55 months follow-up was 188.4 lbs and average BMI was 30.1 kg/m2. Fifteen of the patients were available for follow-up. Thirteen out of 16 (81%) comorbidities in patients available for follow-up were in remission following rapid weight loss. The long-term follow-up and perioperative morbidity shown in this study suggest that LSG and LRYGB appear to be safe and effective operations in morbidly obese adolescents.

Mortality rate after open Roux-in-Y gastric bypass: a 10-year follow-up

The prevalence of obesity has increased to epidemic status worldwide. Thousands of morbidly obese individuals undergo bariatric surgery for sustained weight loss; however, mid- and long-term outcomes of this surgery are still uncertain. Our objective was to estimate the 10-year mortality rate, and determine risk factors associated with death in young morbidly obese adults who underwent bariatric surgery. All patients who underwent open Roux-in-Y gastric bypass surgery between 2001 and 2010, covered by an insurance company, were analyzed to determine possible associations between risk factors present at the time of surgery and deaths related and unrelated to the surgery. Among the 4344 patients included in the study, 79% were female with a median age of 34.9 years and median body mass index (BMI) of 42 kg/m². The 30-day and 10-year mortality rates were 0.55 and 3.34%, respectively, and 53.7% of deaths were related to early or late complications following bariatric surgery. Among these, 42.7% of the deaths were due to sepsis and 24.3% to cardiovascular complications. Male gender, age ≥50 years, BMI ≥50 kg/m², and hypertension significantly increased the hazard for all deaths (P<0.001). Age ≥50 years, BMI ≥50 kg/m², and surgeon inexperience elevated the hazard of death from causes related to surgery. Male gender and age ≥50 years were the factors associated with increased mortality from death not related to surgery. The overall risk of death after bariatric surgery was quite low, and half of the deaths were related to the surgery. Older patients and superobese patients were at greater risk of surgery-related deaths, as were patients operated on by less experienced surgeons.

Cost effective evidence-based interventions to manage obesity in pregnancy

The rising tide of obesity has seen the prevalence of overweight and obese women presenting for antenatal care approach 50% in recent years. In addition, many pregnant women have gestational weight gain in excess of Institute of Medicine guidelines and develop obesity as a result of pregnancy. Both variables impact adversely upon pregnancy outcome. Individualised programs are not financially viable for cash strapped health systems. This review outlines an evidence-based, public health approach to the management of obesity in pregnancy. The interventions are affordable and in randomised and epidemiological trials, achieve benefits in pregnancy outcome.

Periconception weight loss: common sense for mothers, but what about for babies?

Obesity in the childbearing population is increasingly common. Obesity is associated with increased risk for a number of maternal and neonatal pregnancy complications. Some of these complications, such as gestational diabetes, are risk factors for long-term disease in both mother and baby. While clinical practice guidelines advocate for healthy weight prior to pregnancy, there is not a clear directive for achieving healthy weight before conception. There are known benefits to even moderate weight loss prior to pregnancy, but there are potential adverse effects of restricted nutrition during the periconceptional period. Epidemiological and animal studies point to differences in offspring conceived during a time of maternal nutritional restriction. These include changes in hypothalamic-pituitary-adrenal axis function, body composition, glucose metabolism, and cardiovascular function. The periconceptional period is therefore believed to play an important role in programming offspring physiological function and is sensitive to nutritional insult. This review summarizes the evidence to date for offspring programming as a result of maternal periconception weight loss. Further research is needed in humans to clearly identify benefits and potential risks of losing weight in the months before conceiving. This may then inform us of clinical practice guidelines for optimal approaches to achieving a healthy weight before pregnancy.

Fetal growth in pregnancies conceived after gastric bypass surgery in relation to surgery-to-conception interval: a Danish national cohort study

OBJECTIVE

To describe early and late fetal growth in pregnancies conceived after gastric bypass surgery in relation to time from surgery to conception of pregnancy.

METHODS

National cohort study on 387 Danish women, who had laparoscopic or open gastric bypass surgery prior to a singleton pregnancy in which first trimester screening was performed between January 2008 and June 2011. Data were derived from national registers (Danish National Registry of Patients and Danish National Birth Registry, Pregnancy Complications and Abortion-clinical quality database (PreCAb) and the Danish Fetal Medicine Database). Main outcome measures were early and late fetal growth in relation to time from bariatric surgery to conception of the pregnancy. Early fetal growth was expressed as "Fetal Growth Index": the ratio between the estimated number of days from first trimester ultrasound to second trimester ultrasound biometries and the actual calender time elapsed in days. Late fetal growth was expressed as the observed versus expected birthweight according to gestational age (GA).

RESULTS

The surgery-to-conception interval ranged from 3 to 1851 days with a mean value of 502 (SD, 351) days. The mean "fetal growth index" was 0.99 (SD, 0.02) days/day and thus significantly lower than in the background population (mean, 1.04 (SD, 0.09) days/day, p<0.0001). The proportion of infants being small for gestational age was 18.8% and the proportion of large for gestational age infants was 6.7%. The correlation coefficients between surgery-to-conception time and "fetal growth index" and birthweight according to GA were 0.01 (p = 0.8) and 0.04 (p = 0.4), respectively.

CONCLUSION

Fetal growth index was lower than reported in the background population. No correlation was found between the surgery-to-conception interval and early or late fetal growth in pregnancies conceived after gastric bypass surgery.