Table 2 GRADE summary of obstetric outcomes of methods used in the management of maternal obesity.

Gestational diabetes mellitus

14 RCTs

597/2902 [20.6%]

654/2878 [22.7%]

OR 0.88 [0.78 to 1.00]

22 fewerper 1.000 [from 41 fewer to 0 fewer]

⨁⨁⨁⨁ High

Weight loss intervention in maternal obesity does not affect or possibly reduces gestational diabetes.

Gestational hypertension

7 RCTs

60/685 [8.8%]

67/693 [9.7%]

OR 0.92 [0.64 to 1.33]

7 fewerper 1.000 [from 33 fewer to 28 more]

⨁⨁⨁⨁ High

Weight loss intervention in maternal obesity does not affect or possibly reduces gestational hypertension.

Pre-eclampsi

6 RCTs

69/1724 [4.0%]

64/1739 [3.7%]

OR 1.10 [0.78 to 1.56]

4 more per 1.000 [from 8 fewer to 19 more]

⨁⨁⨁◯ Moderate

Eclampsia

1 RCTs

6/783 [0.8%]

10/772 [1.3%]

OR 0.59 [0.21 to 1.63]

5 fewerper 1.000 [from 10 fewer to 8 more]

⨁⨁◯◯ Low

Excessive weight gain during pregnancy

3 RCTs

120/383 [31.3%]

107/393 [27.2%]

OR 1.07 [0.54 to 2.13]

14 more per 1.000 [from 104 fewer to 171 more]

⨁⨁⨁◯ Moderate

Abortion

2 RCTs

25/1009 [2.5%]

16/995 [1.6%]

OR 1.55 [0.82 to 2.93]

9 more per 1.000 [from 3 fewer to 30 more]

⨁⨁⨁◯ Moderate

Gestational weight gain

10 RCTs

2206

2218

-

MD 1.24 lower [1.83 lower to 0.65 lower]

⨁⨁⨁⨁ High

Management of maternal obesity reduces weight gain during pregnancy.

Vaginal delivery

8 RCTs

741/1457 [50.9%]

787/1550 [50.8%]

OR 1.04 [0.90 to 1.20]

10 more per 1.000 [from 26 fewer to 45 more]

⨁⨁⨁⨁ High

Weight loss intervention in maternal obesity does not affect or possibly increase the rate of vaginal delivery.

Instrumental delivery

8 RCTs

161/1416 [11.4%]

162/1495 [10.8%]

OR 1.03 [0.82 to 1.30]

3 more per 1.000 [from 18 fewer to 28 more]

⨁⨁⨁⨁ High

Weight loss intervention in maternal obesity does not affect or possibly increase the rate of instrumental delivery.

Elective cesarean delivery

6 RCTs

245/1253 [19.6%]

242/1357 [17.8%]

OR 1.03 [0.71 to 1.50]

4 more per 1.000 [from 45 fewer to 67 more]

⨁⨁⨁◯ Moderate

Emergency cesarean delivery

6 RCTs

193/1253 [15.4%]

247/1357 [18.2%]

OR 0.89 [0.58 to 1.36]

17 fewerper 1.000 [from 68 fewer to 50 more]

⨁⨁⨁◯ Moderate

Cesarean delivery

12 RCTs

587/1832 [32.0%]

667/1928 [34.6%]

OR 0.89 [0.78 to 1.02]

26 fewerper 1.000 [from 54 fewer to 4 more]

⨁⨁⨁⨁ High

Weight loss intervention in maternal obesity does not affect or possibly reduces cesarean delivery.

Preterm delivery

7 RCTs

31/1381 [2.2%]

29/1388 [2.1%]

OR 1.10 [0.66 to 1.83]

2 more per 1.000 [from 7 fewer to 17 more]

⨁⨁⨁⨁ High

Induction of labour

4 RCTs

321/1013 [31.7%]

339/993 [34.1%]

OR 0.90 [0.74 to 1.08]

23 fewerper 1.000 [from 64 fewer to 18 more]

⨁⨁⨁⨁ High

Weight loss intervention in maternal obesity does not affect or possibly reduces induction of labor.

Perineal laceration

1 RCTs

4/18 [22.2%]

2/10 [20.0%]

OR 1.14 [0.17 to 7.69]

22 more per 1.000 [from 159 fewer to 458 more]

⨁⨁⨁◯ Moderate

Large for gestational age

9 RCTs

158/1881 [8.4%]

192/1915 [10.0%]

OR 0.85 [0.54 to 1.33]

14 fewerper 1.000 [from 44 fewer to 29 more]

⨁⨁⨁⨁ High

Weight loss intervention in maternal obesity does not affect or possibly reduces the birth of large babies by gestational month.

Small for gestational age

5 RCTs

42/741 [5.7%]

35/736 [4.8%]

OR 1.20 [0.76 to 1.90]

9 more per 1.000 [from 11 fewer to 39 more]

⨁⨁⨁⨁ High

Weight loss intervention in maternal obesity does not affect or possibly increase the rate of small for gestational age

Macrosomia

10 RCTs

254/1939 [13.1%]

276/1951 [14.1%]

OR 0.90 [0.75 to 1.09]

12 fewerper 1.000 [from 31 fewer to 11 more]

⨁⨁⨁⨁ High

Weight loss intervention in maternal obesity does not affect or possibly reduces the birth of macrosomia

Low birth weight

3 RCTs

30/665 [4.5%]

34/656 [5.2%]

OR 0.86 [0.52 to 1.43]

7 fewerper 1.000 [from 24 fewer to 21 more]

⨁⨁⨁⨁ High

Weight loss intervention in maternal obesity does not affect or possibly reduces the birth of Low birth weight

Congenital anomaly

2 RCTs

12/1009 [1.2%]

14/995 [1.4%]

OR 0.84 [0.39 to 1.84]

2 fewerper 1.000 [from 9 fewer to 12 more]

⨁⨁⨁◯ Moderate

Neonatal intensive care unit admission

5 RCTs

89/1136 [7.8%]

105/1143 [9.2%]

OR 0.86 [0.64 to 1.15]

12 fewerper 1.000 [from 31 fewer to 12 more]

⨁⨁⨁◯ Moderate

Weight management interventions used during pregnancy may possibly reduce neonatal intensive care unit admission.

Perinatal death

2 RCTs

10/1009 [1.0%]

14/995 [1.4%]

OR 0.70 [0.31 to 1.59]

4 fewerper 1.000 [from 10 fewer to 8 more]

⨁⨁⨁◯ Moderate

Birth weight

14 RCTs

2372

2448

-

MD 51.84 lower [85.86 lower to 17.83 lower]

⨁⨁⨁⨁ High

Management of maternal obesity reduces birth weight.

Postpartum haemorrhage

2 RCTs

149/1009 [14.8%]

122/995 [12.3%]

OR 1.24 [0.96 to 1.61]

25 more per 1.000 [from 4 fewer to 61 more]

⨁⨁⨁◯ Moderate

reastfeeding problems

2 RCTs

219/592 [37.0%]

311/620 [50.2%]

OR 0.62 [0.28 to 1.35]

117 fewerper 1.000 [from 282 fewer to 74 more]

⨁⨁⨁◯ Moderate