• Nathan Riley, MD

Obgyno Wino Podcast Episode 71 - Obesity in Pregnancy

Updated: May 14

"The greatest thing you can do for another being is to provide the unconditional love that comes from making contact with that place in them that is beyond conditions, which is just pure consciousness, pure essence. That is, once we acknowledge each other as just being, then each of us is free to change optimally. If I can just love you because we are here, then you are free to grow as you need to grow.” - Ram Dass

2017 Bourbon Barrel-Aged Cabernet Sauvignon from Ménage à Trois

PB#156 - Published December 2015 (Reaffirmed 2018)

Five Pearls

  1. Women with obesity are at increased risk for fetal congenital anomalies, c-section, preeclampsia, fetal macrosomia, childhood behavioral/developmental issues, and other bad outcomes.

  2. Pre-conception weight loss to normalize BMI improves maternal and neonatal outcomes.

  3. Weight loss while pregnant is not recommended.

  4. There are a variety of special considerations intrapartum and postpartum for women with obesity.

  5. If your patient undergoes c-section, a thick subcutaneous fat layer should be well-irrigated and approximated with sutures in multiple layers if necessary.


- prevalence is ~40% and rising and trending towards class II and III

- higher in non-Hispanic black women and Mexican American women

Effects of obesity on pregnancy

Pregnancy loss/IUFD

- odds ratio of 1.2 for spontaneous abortion compared to normal weight patients

- 40% higher risk of stillbirth compared to women who are not living with obesity (higher risks with worsening obesity class)

- important to consider nutritional deficiencies if your patient has undergone bariatric surgery

Antepartum/Postpartum complications

- higher risk for c-section, failed trial of labor, endometriosis, wound rupture or dehiscence, and venous thrombosis

- 2x composite morbidity and 5x increased risk of neonatal injury with TOLAC

- labor tends to be longer, pregnancies tend to be prolonged, and IOL rate is higher

- for patients with class III obesity or greater, there is also an increased risk postpartum hemorrhage

- decreased likelihood of successful VBAC

- ~50% of women with obesity gain weight during pregnancy in excess of the IOM's recommendation

- greater likelihood of experiencing hypotension or prolonged FHR decelerations post-epidural (independent of concurrent hypertensive disorder or epidural dose)

- excessive weight gain is an independent risk factor for retaining weight post-pregnancy, which further increases risk of metabolic dysfunction in future pregnancies

- pre-pregnancy obesity is associated with early termination of breastfeeding, postpartum anemia, and depression

Risk of stillbirth by gestational age, all-comers (source: Muglu et al, PLOS 2019)

Antepartum considerations

Fetal/neonatal issues

- higher risk of neural tube defects (NTD), hydrocephaly, and congenital anomalies of the CV system, orofacial, and limbs

- higher risk for macrosomia and abnormal growth (including higher fat accumulation)

- increased risk for childhood obesity and metabolic syndrome (independent of gestational diabetes)

- increased risk for childhood asthma

- increased risk for autism, ADHD, and developmental delay

Management considerations - baby

- ultrasound is less effective in making these diagnoses (obese body habitus interferes with radio waves) (P <0.001)

- fortunately, detection of some of the super common soft markers for aneuploidies is not affected: increased nuchal fold, echogenic bowel, and echogenic intracardiac focus

- serum biomarkers for aneuploidies are also less useful due to increased plasma volume in women with obesity (increased false negative rate)

- weight adjusted ranges are useful in improving detection rate of T18 but not T21

- no special fetal surveillance (antepartum or intrapartum) is warranted in patients with obesity as an isolated complicating factor (although many centers will recommend fetal echo if maternal BMI >40)

Maternal complications

- higher risk of cardiac dysfunction, proteinuria, sleep apnea, fatty liver, GDM, and preeclampsia

Management considerations - mom

- ensure blood pressure cuffs are suitable for larger upper arm circumference

- if your patient has undergone bariatric surgery, glucose screening methods for GDM are not recommended; instead, offer fasting and post-prandial fingerstick glucose checks at home

- women with obesity should also be screened early in pregnancy for obstructive sleep apnea (OSA)

- if patient is considering epidural, consider early placement in labor given that epidurals are difficult to place due to difficulty in palpating anatomic landmarks

- having a reliable neuraxial catheter in place may also be helpful in case an emergency arises, as artificial airways (part of general anesthesia) are difficult to place in women with obesity

Special considerations in the event of c-section

- operating room tables are typically only able to support 450 lbs

- consider how extra straps and equipment may impinge nerves or lead to pressure ulcers

- request extra surgical assistants if helpful for pannus or incision retraction

- longer surgical instruments may be required

- higher doses of antibiotics have been suggested (e.g. cefazolin 3g instead of the standard 2g), but no benefit was found in a RCT

- vertical incision carries higher rate of wound complications compared to transverse

- supraumbilical incision may be beneficial in the case of a large panniculus

- if patient has significant subcutaneous fat stores around the skin incision (>2 cm in depth), irrigate well before closure with subcutaneous approximating sutures!

- placement of subcutaneous drain is useless

- wound vacs can be helpful for healing of c-section skin wounds (keeps it dry, approximated, and clean) --> decreases likelihood of wound separation/dehiscence and infection

Special postpartum considerations

- obesity is an independent risk factor for VTE

- weight-based dosing of anticoagulants is recommended (0.5 mg/kg q12 hrs for up to 6 weeks postpartum)

- superficial wound infections (no purulent drainage, deep layers intact) can generally be managed conservatively through antibiotics

- for more severe or deeper infections, wound exploration and debridement may be warranted

- if you weren't using a wound vac after primary surgery, then use of a wound vac is definitely recommended if you have to reopen the incision

Pre-conception recommendations for women with obesity

- weight loss to a "normal" BMI should be encouraged

- lifestyle modification is the most effective, most lasting means (if you need help with this, I offer my services at no cost...)

- bariatric surgery also an option if lifestyle modification is insufficient

- any weight loss prior to pregnancy in a woman with obesity can improve outcomes - over the long haul, weight loss of 5-7% significantly improves metabolic health

- however, weight loss should not be encouraged while pregnant

76 views0 comments