Very Low Weight Gain or Gestational Weight Loss in Pregnant Obese Women Risky

[Actual news headline and picture from 2009 media release
because, you know, all obese pregnant women are
constantly stuffing their faces with chocolate]

Here is yet another study that confirms the potential risks of extreme restrictions of prenatal weight gain in women of size.

In this study done by the prestigious MFMU Network, gestational weight loss or a very low weight gain (less than the 11-20 lbs. recommended by the Institute of Medicine) in "obese" women was associated with about twice the rate of Small-for-Gestational-Age (SGA) babies.

This is a concern because SGA babies are at higher risk for metabolic disease as they grow older, including insulin resistance, diabetes, abdominal fatness, the metabolic syndrome, and cardiovascular disease.

In the rush to "cure" obesity, are care providers increasing the next generation's risk for the very conditions they are trying to prevent?

Alarmingly, many clinicians continue to advise high-BMI women to gain little or no weight in pregnancy (even with twins), and some are still telling women of size to lose weight during pregnancy.

This study joins several others that should indicate that extreme prenatal weight gain restriction is not advisable.

Reference

Am J Obstet Gynecol. 2014 Feb 11. pii: S0002-9378(14)00121-5. doi: 10.1016/j.ajog.2014.02.004. [Epub ahead of print] Inadequate weight gain in overweight and obese pregnant women: what is the effect on fetal growth? Catalano PM1, Mele L2, Landon MB3, Ramin SM4, Reddy UM5, Casey B6, Wapner RJ7, Varner MW8, Rouse DJ9, Thorp JM Jr10, Saade G11, Sorokin Y12, Peaceman AM13, Tolosa JE14; Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network. PMID: 24530820

OBJECTIVE: We sought to evaluate inadequate gestational weight gain and fetal growth among overweight and obese women. STUDY DESIGN: We conducted an analysis of prospective singleton term pregnancies in which 1053 overweight and obese women gained >5 kg (14.4 ± 6.2 kg) or 188 who either lost or gained ≤5 kg (1.1 ± 4.4 kg). Birthweight, fat mass, and lean mass were assessed using anthropometry. Small for gestational age (SGA) was defined as ≤10th percentile of a standard US population. Univariable and multivariable analysis evaluated the association between weight change and neonatal morphometry. RESULTS: There was no significant difference in age, race, smoking, parity, or gestational age between groups. Weight loss or gain ≤5 kg was associated with SGA, 18/188 (9.6%) vs 51/1053 (4.9%); (adjusted odds ratio, 2.6; 95% confidence interval, 1.4-4.7; P = .003). Neonates of women who lost or gained ≤5 kg had lower birthweight (3258 ± 443 vs 3467 ± 492 g, P < .0001), fat mass (403 ± 175 vs 471 ± 193 g, P < .0001), and lean mass (2855 ± 321 vs 2995 ± 347 g, P < .0001), and smaller length, percent fat mass, and head circumference. Adjusting for diabetic status, prepregnancy body mass index, smoking, parity, study site, gestational age, and sex, neonates of women who gained ≤5 kg had significantly lower birthweight, lean body mass, fat mass, percent fat mass, head circumference, and length. There were no significant differences in neonatal outcomes between those who lost weight and those who gained ≤5 kg. CONCLUSION: In overweight and obese women weight loss or gain ≤5 kg is associated with increased risk of SGA and decreased neonatal fat mass, lean mass, and head circumference.